Helen McNair

Purpose The aim of this study was to investigate prospectively the weekly volume changes in the target volumes and organs at risk and the resulting dosimetric changes during induction chemotherapy followed by chemoradiotherapy with intensity-modulated radiation therapy (C-IMRT) for head-and-neck cancer patients. Methods and Materials Patients receiving C-IMRT for head-and-neck cancer had repeat CT scans at weeks 2, 3, 4, and 5 during radiotherapy. The volume changes of clinical target volume 1 (CTV1) and CTV2 and the resulting dosimetric changes to planning target volume 1 (PTV1) and PTV2 and the organs at risk were measured. Results The most significant volume differences were seen at week 2 for CTV1 and CTV2. The reductions in the volumes of CTV1 and CTV2 at week 2 were 3.2% and 10%, respectively (p = 0.003 and p < 0.001). The volume changes resulted in a significant reduction in the minimum dose to PTV1 and PTV2 (2 Gy, p = 0.002, and 3.9 Gy, p = 0.03, respectively) and an increased dose range across PTV1 and PTV2 (2.5 Gy, p < 0.001, and 5.1 Gy, p = 0.008, respectively). There was a 15% reduction in the parotid volumes by week 2 (p < 0.001) and 31% by week 4 (p < 0.001). There was a statistically significant increase in the mean dose to the ipsilateral parotid only at week 4 (2.7 Gy, p = 0.006). The parotid glands shifted medially by an average of 2.3 mm (p < 0.001) by week 4. Conclusion The most significant volumetric changes and dosimetric alterations in the tumor volumes and organs at risk during a course of C-IMRT occur by week 2 of radiotherapy. Further adaptive radiotherapy with replanning, if appropriate, is recommended. The aim of this study was to investigate prospectively the weekly volume changes in the target volumes and organs at risk and the resulting dosimetric changes during induction chemotherapy followed by chemoradiotherapy with intensity-modulated radiation therapy (C-IMRT) for head-and-neck cancer patients. Patients receiving C-IMRT for head-and-neck cancer had repeat CT scans at weeks 2, 3, 4, and 5 during radiotherapy. The volume changes of clinical target volume 1 (CTV1) and CTV2 and the resulting dosimetric changes to planning target volume 1 (PTV1) and PTV2 and the organs at risk were measured. The most significant volume differences were seen at week 2 for CTV1 and CTV2. The reductions in the volumes of CTV1 and CTV2 at week 2 were 3.2% and 10%, respectively (p = 0.003 and p < 0.001). The volume changes resulted in a significant reduction in the minimum dose to PTV1 and PTV2 (2 Gy, p = 0.002, and 3.9 Gy, p = 0.03, respectively) and an increased dose range across PTV1 and PTV2 (2.5 Gy, p < 0.001, and 5.1 Gy, p = 0.008, respectively). There was a 15% reduction in the parotid volumes by week 2 (p < 0.001) and 31% by week 4 (p < 0.001). There was a statistically significant increase in the mean dose to the ipsilateral parotid only at week 4 (2.7 Gy, p = 0.006). The parotid glands shifted medially by an average of 2.3 mm (p < 0.001) by week 4. The most significant volumetric changes and dosimetric alterations in the tumor volumes and organs at risk during a course of C-IMRT occur by week 2 of radiotherapy. Further adaptive radiotherapy with replanning, if appropriate, is recommended.

The past decade has provided many technological advances in radiotherapy. The European Institute of Radiotherapy (EIR) was established by the European Society of Therapeutic Radiology and Oncology (ESTRO) to provide current consensus statement with evidence-based and pragmatic guidelines on topics of practical relevance for radiation oncology. This report focuses primarily on 3D CT-based in-room image guidance (3DCT-IGRT) systems. It will provide an overview and current standing of 3DCT-IGRT systems addressing the rationale, objectives, principles, applications, and process pathways, both clinical and technical for treatment delivery and quality assurance. These are reviewed for four categories of solutions; kV CT and kV CBCT (cone-beam CT) as well as MV CT and MV CBCT. It will also provide a framework and checklist to consider the capability and functionality of these systems as well as the resources needed for implementation. Two different but typical clinical cases (tonsillar and prostate cancer) using 3DCT-IGRT are illustrated with workflow processes via feedback questionnaires from several large clinical centres currently utilizing these systems. The feedback from these clinical centres demonstrates a wide variability based on local practices. This report whilst comprehensive is not exhaustive as this area of development remains a very active field for research and development. However, it should serve as a practical guide and framework for all professional groups within the field, focussed on clinicians, physicists and radiation therapy technologists interested in IGRT.

<h2>Abstract</h2><h3>Purpose</h3> To determine whether voluntary deep-inspiratory breath-hold (v_DIBH) and deep-inspiratory breath-hold with the active breathing coordinator™ (ABC_DIBH) in patients undergoing left breast radiotherapy are comparable in terms of normal-tissue sparing, positional reproducibility and feasibility of delivery. <h3>Methods</h3> Following surgery for early breast cancer, patients underwent planning-CT scans in v_DIBH and ABC_DIBH. Patients were randomised to receive one technique for fractions 1–7 and the second technique for fractions 8–15 (40Gy/15 fractions total). Daily electronic portal imaging (EPI) was performed and matched to digitally-reconstructed radiographs. Cone-beam CT (CBCT) images were acquired for 6/15 fractions and matched to planning-CT data. Population systematic (<i>Σ</i>) and random errors (<i>σ</i>) were estimated. Heart, left-anterior-descending coronary artery, and lung doses were calculated. Patient comfort, radiographer satisfaction and scanning/treatment times were recorded. Within-patient comparisons between the two techniques used the paired <i>t</i>-test or Wilcoxon signed-rank test. <h3>Results</h3> Twenty-three patients were recruited. All completed treatment with both techniques. EPI-derived <i>Σ</i> were ⩽1.8mm (v_DIBH) and ⩽2.0mm (ABC_DIBH) and <i>σ</i> ⩽2.5mm (v_DIBH) and ⩽2.2mm (ABC_DIBH) (all <i>p</i> non-significant). CBCT-derived <i>Σ</i> were ⩽3.9mm (v_DIBH) and ⩽4.9mm (ABC_DIBH) and <i>σ</i> ⩽4.1mm (v_DIBH) and ⩽3.8mm (ABC_DIBH). There was no significant difference between techniques in terms of normal-tissue doses (all <i>p</i> non-significant). Patients and radiographers preferred v_DIBH (<i>p</i>=0.007, <i>p</i>=0.03, respectively). Scanning/treatment setup times were shorter for v_DIBH (<i>p</i>=0.02, <i>p</i>=0.04, respectively). <h3>Conclusions</h3> v_DIBH and ABC_DIBH are comparable in terms of positional reproducibility and normal tissue sparing. v_DIBH is preferred by patients and radiographers, takes less time to deliver, and is cheaper than ABC_DIBH.

<h3>Purpose</h3> The purpose of this study was to establish reproducible guidelines for delineating the clinical target volume (CTV) of the pelvic lymph nodes (LN) by combining the freehand Royal Marsden Hospital (RMH) and Radiation Therapy Oncology Group (RTOG) vascular expansion techniques. <h3>Methods and Materials</h3> Seven patients with prostate cancer underwent standard planning computed tomography scanning. Four different CTVs (RMH, RTOG, modified RTOG, and Prostate and pelvIs Versus prOsTate Alone treatment for Locally advanced prostate cancer [PIVOTAL] trial) were created for each patient, and 6 different bowel expansion margins (BEM) were created to assess bowel avoidance by the CTV. The resulting CTVs were compared visually and by using Jaccard conformity indices. The volume of overlap between bowel and planning target volume (PTV) was measured to aid selection of an appropriate BEM to enable maximal LN yet minimal normal tissue coverage. <h3>Results</h3> In total, 84 nodal contours were evaluated. LN coverage was similar in all groups, with all of the vascular-expansion techniques (RTOG, modified RTOG, and PIVOTAL), resulting in larger CTVs than that of the RMH technique (mean volumes: 287.3 cm³, 326.7 cm³, 310.3 cm³, and 256.7 cm³, respectively). Mean volumes of bowel within the modified RTOG PTV were 19.5 cm³ (with 0 mm BEM), 17.4 cm³ (1-mm BEM), 10.8 cm³ (2-mm BEM), 6.9 cm³ (3-mm BEM), 5.0 cm³ (4-mm BEM), and 1.4 cm³ (5-mm BEM) in comparison with an overlap of 9.2 cm³ seen using the RMH technique. Evaluation of conformity between LN-CTVs from each technique revealed similar volumes and coverage. <h3>Conclusions</h3> Vascular expansion techniques result in larger LN-CTVs than the freehand RMH technique. Because the RMH technique is supported by phase 1 and 2 trial safety data, we proposed modifications to the RTOG technique, including the addition of a 3-mm BEM, which resulted in LN-CTV coverage similar to that of the RMH technique, with reduction in bowel and planning target volume overlap. On the basis of these findings, recommended guidelines including a detailed pelvic LN contouring atlas have been produced and implemented in the PIVOTAL trial.

IntroductionMR-guided adapted radiotherapy (MRgART) using a high field MR-linac has recently become available. We report the estimated delivered fractional dose of the first five prostate cancer patients treated at our centre using MRgART and compare this to C-Arm linac daily Image Guided Radiotherapy (IGRT).MethodsPatients were treated using adapted treatment plans shaped to their daily anatomy. The treatments were recalculated on an MR image acquired immediately prior to treatment delivery in order to estimate the delivered fractional dose. C-arm linac non-adapted VMAT treatment plans were recalculated on the same MR images to estimate the fractional dose that would have been delivered using conventional radiotherapy techniques using a daily IGRT protocol.Results95% and 93% of mandatory target coverage objectives and organ at risk dose constraints were achieved by MRgART and C-arm linac delivered dose estimates, respectively. Both delivery techniques were estimated to have achieved 98% of mandatory Organ At Risk (OAR) dose constraints whereas for the target clinical goals, 86% and 80% were achieved by MRgART and C-arm linac delivered dose estimates.ConclusionsProstate MRgART can be delivered using the a high field MR-linac. Radiotherapy performed on a C-arm linac offers a good solution for prostate cancer patients who present with favourable anatomy at the time of reference imaging and demonstrate stable anatomy throughout the course of their treatment. For patients with critical OARs abutting target volumes on their reference image we have demonstrated the potential for a target dose coverage improvement for MRgART compared to C-arm linac treatment.

<h2>Abstract</h2> Online magnetic resonance-guided radiotherapy (oMRgRT) represents one of the most innovative applications of current image-guided radiation therapy (IGRT). The revolutionary concept of oMRgRT systems is the ability to acquire MR images for adaptive treatment planning and also online imaging during treatment delivery. The daily adaptive planning strategies allow to improve targeting accuracy while avoiding critical structures. This ESTRO-ACROP recommendation aims to provide an overview of available systems and guidance for best practice in the implementation phase of hybrid MR-linac systems. Unlike the implementation of other radiotherapy techniques, oMRgRT adds the MR environment to the daily practice of radiotherapy, which might be a new experience for many centers. New issues and challenges that need to be thoroughly explored before starting clinical treatments will be highlighted.

The use of breath-hold techniques in radiotherapy, such as deep-inspiration breath hold, is increasing although guidelines for clinical implementation are lacking. In these recommendations, we aim to provide an overview of available technical solutions and guidance for best practice in the implementation phase. We will discuss specific challenges in different tumour sites including factors such as staff training and patient coaching, accuracy, and reproducibility. In addition, we aim to highlight the need for further research in specific patient groups. This report also reviews considerations for equipment, staff training and patient coaching, as well as image guidance for breath-hold treatments. Dedicated sections for specific indications, namely breast cancer, thoracic and abdominal tumours are also included.

Background and purpose Patients receiving radical radiotherapy to the prostate are requested to maintain a full bladder to displace the dome of the bladder and small bowel from the target volume. This study investigated patients' ability to consistently maintain a full bladder throughout planning and treatment before (Study 1) and after (Study 2) the introduction of a patient information sheet. Patients and methods Bladder volumes were measured on 41 patients at CT scanning, simulation and once weekly during treatment using a portable ultrasound device, BladderScan™ BVI 3000. Patients were asked their assessment of bladder fullness, time since last urination and the volume of fluid drank. A patient information sheet on bladder filling was then introduced and the study repeated on 25 patients (Study 2). The ultrasound bladder volumes measured at CT were compared to the CT scan data. Results There was a strong correlation between the ultrasound and CT bladder volumes r=0.88 (P<0.01). There was a significant decrease between the volume at CT (mean 362 ml, SD 229 ml) and treatment (mean 251 ml, SD 171 ml) in Study 1 (P=0.002). In Study 2 the mean volume at CT was 286 ml (SD 164 ml) compared to a mean of 312 ml (SD 196 ml) during treatment. The measured volume correlated with patient self-assessment (r=0.47, P<0.01). The median volume drank by patients in Study 2 was 350 ml (range 50–825 ml) compared to 450 ml (range 75–1500 ml) in Study 1. Conclusions Our initial results showed patients were unable to maintain a constant bladder volume during planning and treatment. Implementation of written bladder filling instructions was shown to improve bladder volume consistency.

To examine patterns of bladder wall motion during high-dose hypofractionated bladder radiotherapy and to validate a novel adaptive planning method, A-POLO, to prevent subsequent geographic miss.Patterns of individual bladder filling were obtained with repeat computed tomography planning scans at 0, 15, and 30minutes after voiding. A series of patient-specific plans corresponding to these time-displacement points was created. Pretreatment cone-beam computed tomography was performed before each fraction and assessed retrospectively for adaptive intervention. In fractions that would have required intervention, the most appropriate plan was chosen from the patient's "library," and the resulting target coverage was reassessed with repeat cone-beam computed tomography.A large variation in patterns of bladder filling and interfraction displacement was seen. During radiotherapy, predominant translations occurred cranially (maximum 2.5 cm) and anteriorly (maximum 1.75 cm). No apparent explanation was found for this variation using pretreatment patient factors. A need for adaptive planning was demonstrated by 51% of fractions, and 73% of fractions would have been delivered correctly using A-POLO. The adaptive strategy improved target coverage and was able to account for intrafraction motion also.Bladder volume variation will result in geographic miss in a high proportion of delivered bladder radiotherapy treatments. The A-POLO strategy can be used to correct for this and can be implemented from the first fraction of radiotherapy; thus, it is particularly suited to hypofractionated bladder radiotherapy regimens.

PurposeTo compare mean heart and left anterior descending coronary artery (LAD) doses (NTDmean) and positional reproducibility in larger-breasted women receiving left breast radiotherapy using supine voluntary deep-inspiratory breath-hold (VBH) and free-breathing prone techniques.Materials and methodsFollowing surgery for early breast cancer, patients with estimated breast volumes >750 cm3 underwent planning-CT scans in supine VBH and free-breathing prone positions. Radiotherapy treatment plans were prepared, and mean heart and LAD doses were calculated. Patients were randomised to receive one technique for fractions 1–7, before switching techniques for fractions 8–15 (40 Gy/15 fractions total). Daily electronic portal imaging and alternate-day cone-beam CT (CBCT) imaging were performed. The primary endpoint was the difference in mean LAD NTDmean between techniques. Population systematic (Σ) and random errors (σ) were estimated. Within-patient comparisons between techniques used Wilcoxon signed-rank tests.Results34 patients were recruited, with complete dosimetric data available for 28. Mean heart and LAD NTDmean doses for VBH and prone treatments respectively were 0.4 and 0.7 (p< 0.001) and 2.9 and 7.8 (p< 0.001). Clip-based CBCT errors for VBH and prone respectively were ⩽3.0 mm and ⩽6.5 mm (Σ) and ⩽3.5 mm and ⩽5.4 mm (σ).ConclusionsIn larger-breasted women, supine VBH provided superior cardiac sparing and reproducibility than a free-breathing prone position.

Adaptive bladder radiotherapy, with plan of the day selection and plan library development based on individual filling patterns, has been previously modelled in patients receiving weekly hypofractionated treatment and improved geometric accuracy has been shown. The aim of this study was to assess the clinical implementation of the technique.Conformal plans (with small, intermediate and large planning target volumes) were developed for 25 patients. After pre-treatment cone-beam computed tomography, the optimal plan of the day was selected and delivered by two trained observers. Independent off-line plan selection was also carried out. Concordance between the on-line and off-line selections, frequency of plan usage, target coverage and normal tissue sparing were assessed.Plan selection concordance was 91%. Fifty-five per cent of fractions were delivered using small or large plans. The mean coverage of the clinical target volume by the 95% isodose was 99%. The mean reduction in the volume of normal tissue treated to 95% of the prescription dose was 219 cm(3) compared with the previous institutional standard approach.Good concordance in plan selection is shown with clinical implementation of the adaptive strategy. Adequate target coverage was achieved with reduction in the volume of normal tissue irradiated to a high dose compared with the previous standard approach.

With increasing incorporation of MRI in radiotherapy, we investigate two MRI sequences for prostate delineation in radiographer-led image guidance.Five therapeutic radiographers contoured the prostate individually on CT, T2 weighted (T2W) and T2* weighted (T2*W) imaging for 10 patients. Contours were analysed with Monaco ADMIRE (research v. 2.0) to assess interobserver variability and accuracy by comparison with a gold standard clinician contour. Observers recorded time taken for contouring and scored image quality and confidence in contouring.There is good agreement when comparing radiographer contours to the gold-standard for all three imaging types with Dice similarity co-efficient 0.91-0.94, Cohen's κ 0.85-0.91, Hausdorff distance 4.6-7.6 mm and mean distance between contours 0.9-1.2 mm. In addition, there is good concordance between radiographers across all imaging modalities. Both T2W and T2*W MRI show reduced interobserver variability and improved accuracy compared to CT, this was statistically significant for T2*W imaging compared to CT across all four comparison metrics. Comparing MRI sequences reveals significantly reduced interobserver variability and significantly improved accuracy on T2*W compared to T2W MRI for DSC and Cohen's κ. Both MRI sequences scored significantly higher compared to CT for image quality and confidence in contouring, particularly T2*W. This was also reflected in the shorter time for contouring, measuring 15.4, 9.6 and 9.8 min for CT, T2W and T2*W MRI respectively. Conclusion: Therapeutic radiographer prostate contours are more accurate, show less interobserver variability and are more confidently and quickly outlined on MRI compared to CT, particularly using T2*W MRI. Advances in knowledge: Our work is relevant for MRI sequence choice and development of the roles of the interprofessional team in the advancement of MRI-guided radiotherapy.

PurposeTo report a planned analysis of the efficacy and toxicity of dose escalation to the intraprostatic dominant nodule identified on multiparametric magnetic resonance imaging using standard and hypofractionated external beam radiation therapy.Methods and MaterialsDELINEATE is a single centre prospective phase 2 multicohort study including standard (cohort A: 74 Gy in 37 fractions) and moderately hypofractionated (cohort B: 60 Gy in 20 fractions) prostate image guided intensity modulated radiation therapy in patients with National Comprehensive Cancer Network intermediate- and high-risk disease. Patients received an integrated boost of 82 Gy (cohort A) and 67 Gy (cohort B) to lesions visible on multiparametric magnetic resonance imaging. Fifty-five patients were treated in cohort A, and 158 patients were treated in cohort B; the first 50 sequentially treated patients in cohort B were included in this planned analysis. The primary endpoint was late Radiation Therapy Oncology Group rectal toxicity at 1 year. Secondary endpoints included acute and late toxicity measured with clinician- and patient-reported outcomes at other time points and biochemical relapse–free survival for cohort A. Median follow-up was 74.5 months for cohort A and 52.0 months for cohort B.ResultsIn cohorts A and B, 27% and 40% of patients, respectively, were classified as having National Comprehensive Cancer Network high-risk disease. The cumulative 1-year incidence of Radiation Therapy Oncology Group grade 2 or worse rectal and urinary toxicity was 3.6% and 0% in cohort A and 8% and 10% in cohort B, respectively. There was no reported late grade 3 rectal toxicity in either cohort. Within cohort A, 4 of 55 (7%) patients had biochemical relapse.ConclusionsDelivery of a simultaneous integrated boost to intraprostatic dominant nodules is feasible in prostate radiation therapy using standard and moderately hypofractionated regimens, with rectal and genitourinary toxicity comparable to contemporary series without an intraprostatic boost. To report a planned analysis of the efficacy and toxicity of dose escalation to the intraprostatic dominant nodule identified on multiparametric magnetic resonance imaging using standard and hypofractionated external beam radiation therapy. DELINEATE is a single centre prospective phase 2 multicohort study including standard (cohort A: 74 Gy in 37 fractions) and moderately hypofractionated (cohort B: 60 Gy in 20 fractions) prostate image guided intensity modulated radiation therapy in patients with National Comprehensive Cancer Network intermediate- and high-risk disease. Patients received an integrated boost of 82 Gy (cohort A) and 67 Gy (cohort B) to lesions visible on multiparametric magnetic resonance imaging. Fifty-five patients were treated in cohort A, and 158 patients were treated in cohort B; the first 50 sequentially treated patients in cohort B were included in this planned analysis. The primary endpoint was late Radiation Therapy Oncology Group rectal toxicity at 1 year. Secondary endpoints included acute and late toxicity measured with clinician- and patient-reported outcomes at other time points and biochemical relapse–free survival for cohort A. Median follow-up was 74.5 months for cohort A and 52.0 months for cohort B. In cohorts A and B, 27% and 40% of patients, respectively, were classified as having National Comprehensive Cancer Network high-risk disease. The cumulative 1-year incidence of Radiation Therapy Oncology Group grade 2 or worse rectal and urinary toxicity was 3.6% and 0% in cohort A and 8% and 10% in cohort B, respectively. There was no reported late grade 3 rectal toxicity in either cohort. Within cohort A, 4 of 55 (7%) patients had biochemical relapse. Delivery of a simultaneous integrated boost to intraprostatic dominant nodules is feasible in prostate radiation therapy using standard and moderately hypofractionated regimens, with rectal and genitourinary toxicity comparable to contemporary series without an intraprostatic boost.

IntroductionStereotactic body radiotherapy (SBRT) is an established ablative treatment for liver tumors with excellent local control rates. Magnetic resonance imaging guided radiotherapy (MRgRT) provides superior soft tissue contrast and may therefore facilitate a marker-less liver SBRT workflow. The goal of the present study was to investigate feasibility, workflow parameters, toxicity and patient acceptance of MRgSBRT on a 1.5 T MR-Linac.MethodsTen consecutive patients with liver metastases treated on a 1.5 T MR-Linac were included in this prospective trial. Tumor delineation was performed on four-dimensional computed tomography scans and both exhale triggered and free-breathing T2 MRI scans from the MR-Linac. An internal target volume based approach was applied. Organ at risk constraints were based on the UKSABR guidelines (Version 6.1). Patient acceptance regarding device specific aspects was assessed and toxicity was scored according to the common toxicity criteria of adverse events, version 5.ResultsNine of ten tumors were clearly visible on the 1.5 T MR-Linac. No patient had fiducial markers placed for treatment. All patients were treated with three or five fractions. Median dose to 98% of the gross tumor volume was 38.5 Gy. The median time from “patient identity check” until “beam-off” was 31 min. Median beam on time was 9.6 min. Online MRgRT was well accepted in general and no treatment had to be interrupted on patient request. No event of symptomatic radiation induced liver disease was observed after a median follow-up of ten month (range 3–17 months).ConclusionOur early experience suggests that online 1.5 T MRgSBRT of liver metastases represents a promising new non-invasive marker-free treatment modality based on high image quality, clinically reasonable in-room times and high patient acceptance. Further studies are necessary to assess clinical outcome, to validate advanced motion management and to explore the benefit of online response adaptive liver SBRT.

The implementation of MRI-guided online adaptive radiotherapy has facilitated the extension of therapeutic radiographers' roles to include contouring, thus releasing the clinician from attending daily treatment. Following undergoing a specifically designed training programme, an online interobserver variability study was performed.117 images from six patients treated on a MR Linac were contoured online by either radiographer or clinician and the same images contoured offline by the alternate profession. Dice similarity coefficient (DSC), mean distance to agreement (MDA), Hausdorff distance (HD) and volume metrics were used to analyse contours. Additionally, the online radiographer contours and optimised plans (n = 59) were analysed using the offline clinician defined contours. After clinical implementation of radiographer contouring, target volume comparison and dose analysis was performed on 20 contours from five patients.Comparison of the radiographers' and clinicians' contours resulted in a median (range) DSC of 0.92 (0.86 - 0.99), median (range) MDA of 0.98 mm (0.2-1.7) and median (range) HD of 6.3 mm (2.5-11.5) for all 117 fractions. There was no significant difference in volume size between the two groups. Of the 59 plans created with radiographer online contours and overlaid with clinicians' offline contours, 39 met mandatory dose constraints and 12 were acceptable because 95 % of the high dose PTV was covered by 95 % dose, or the high dose PTV was within 3 % of online plan. A clinician blindly reviewed the eight remaining fractions and, using trial quality assurance metrics, deemed all to be acceptable. Following clinical implementation of radiographer contouring, the median (range) DSC of CTV was 0.93 (0.88-1.0), median (range) MDA was 0.8 mm (0.04-1.18) and HD was 5.15 mm (2.09-8.54) respectively. Of the 20 plans created using radiographer online contours overlaid with clinicians' offline contours, 18 met the dosimetric success criteria, the remaining 2 were deemed acceptable by a clinician.Radiographer and clinician prostate and seminal vesicle contours on MRI for an online adaptive workflow are comparable and produce clinically acceptable plans. Radiographer contouring for prostate treatment on a MR-linac can be effectively introduced with appropriate training and evaluation. A DSC threshold for target structures could be implemented to streamline future training.

Patients with non-small cell lung cancer (NSCLC) often have inhomogeneous lung perfusion. Radiotherapy planning computed tomography (CT) scans have been accurately co-registered with lung perfusion single photon emission computed tomography (SPECT) scans to design radiotherapy treatments which limit dose to healthy 'perfused' lung.Patients with localised NSCLC had CT and SPECT scans accurately co-registered in the planning system. The SPECT images were used to define a volume of perfused 'functioning' lung (FL). Inverse planning software was used to create 3D-conformal plans, the planning objective being either to minimise the dose to whole lungs (WL) or to minimise the dose to FL.Four plans were created for each of six patients. The mean difference in volume between WL and FL was 1011.7 cm(3) (range 596.2-1581.1cm(3)). One patient with bilateral upper lobe perfusion deficits had a 16% reduction in FLV(20) (the percentage volume of functioning lung receiving >or=20 Gy). The remaining patients had inhomogeneous perfusion deficits such that inverse planning was not able to sufficiently optimise beam angles to avoid functioning lung.SPECT perfusion images can be accurately co-registered with radiotherapy planning CT scans and may be helpful in creating treatment plans for patients with large perfusion deficits.

Background The effectiveness of ABC has been traditionally measured as the reduction in internal margin (IM) within the planning target volume (PTV). Not to overestimate the benefit of ABC, the effect of patient movement during treatment also needs to be taken into account. We determined the IM and set-up error with ABC and the effect on physical lung parameters compared to standard margins used with free breathing. We also assessed interfraction oesophageal movement to determine a planning organ at risk volume (PRV). Materials and methods Two sequential studies were performed using ABC in NSCLC patients suitable for radical radiotherapy (RT). Twelve out of 14 patients in Study 1 had tumours visible fluoroscopically and had intrafraction tumour movement assessed with and without ABC. Sixteen patients were recruited to Study 2 and had interfraction tumour movement measured using ABC in a moderate deep inspiration breath-hold, of these 7 patients also had interfraction oesophageal movement recorded. Interfraction movement was assessed by CT scan prior to and in the middle and final week of RT. Displacement of the tumour centre of mass and oesophageal borders relative to the first scan provided a measure of movement. Set-up error was measured in 9 patients treated with an in-house lung board adapted for the ABC device. Combining movement and set-up errors determined PTV and PRV margins with ABC. The effect of ABC on mean lung dose (MLD), lung V20 and V13 was calculated. Results ABC in a moderate deep inspiration breath-hold was tolerated in 25 out of 30 patients (83%) in Study 1 and 2. The random contribution of periodic tumour motion was reduced by 90% in the y direction with ABC compared to free-breathing. The magnitude of motion reduction was less in the x and z direction. Combining the systematic and random set-up error in quadrature with the systematic and random intrafraction and interfraction tumour variations with ABC results in a PTV margin of 8.3 mm in the x direction, 12.0 mm in the y direction and 9.8 mm in the z direction. There was a relative mean reduction in MLD, lung V20 and V13 of 25%, 21% and 18% with the ABC PTV compared to a free-breathing PTV. Oesophageal movement combined with set-up error resulted in an isotropic PRV of 4.7 mm. Conclusions The reduction in PTV size with ABC resulted in an 18–25% relative reduction in physical lung parameters. PTV margin reduction has the potential to spare normal lung and allow dose-escalation if coupled with image-guided RT. The oesophageal PRV needs to be considered when irradiating central disease and is of increasing importance with altered RT fractionation and concomitant chemoradiation schedules. Further reductions in PTV and PRV may be possible if patient set-up error was minimised, confirming that attention to patient immobilisation is as important as attempts to control tumour motion.

IntroductionOne method to overcome the problem of lung tumour movement in patients treated with radiotherapy is to restrict tumour motion with an Active Breathing Control (ABC) device.This study evaluated the feasibility of using ABC in patients receiving radical radiotherapy for non small cell lung cancer.Method 18 patients, median (range) age of 66 (44-82)years, were consented for the study.A training session was conducted to establish the patient's breath hold level and breath hold time.Three planning scans were acquired using the ABC device.Reproducibility of breath hold was assessed by comparing lung volumes measured from the planning scans and the volume recorded by ABC.Patients were treated with a 3-field coplanar beam arrangement and treatment time (patient on and off the bed) and number of breath holds recorded.The tolerability of the device was assessed by weekly questionnaire.Quality assurance was performed on the two ABC devices used. Results17/18 patients completed 32 fractions of radiotherapy using ABC.All patients tolerated a maximum breath hold time >15secs.The mean (SD) patient training time was 13.8 (4.8) min and no patient found the ABC very uncomfortable.6-13 breath holds of 10-14 secs were required per session.The mean treatment time was 15.8 mins (5.8 mins).The breath hold volumes were reproducible during treatment and also between the two ABC devices. ConclusionThe use of ABC in patients receiving radical radiotherapy for NSCLC is feasible.It was not possible to predict a patient's ability to breath hold.A minimum tolerated breath hold time of 15 seconds is recommended prior to commencing treatment.

To evaluate the utility of intraprostatic markers in the treatment verification of prostate cancer radiotherapy. Specific aims were: to compare the effectiveness of offline correction protocols, either using gold markers or bony anatomy; to estimate the potential benefit of online correction protocol's using gold markers; to determine the presence and effect of intrafraction motion.Thirty patients with three gold markers inserted had pretreatment and posttreatment images acquired and were treated using an offline correction protocol and gold markers. Retrospectively, an offline protocol was applied using bony anatomy and an online protocol using gold markers.The systematic errors were reduced from 1.3, 1.9, and 2.5 mm to 1.1, 1.1, and 1.5 mm in the right-left (RL), superoinferior (SI), and anteroposterior (AP) directions, respectively, using the offline correction protocol and gold markers instead of bony anatomy. The subsequent decrease in margins was 1.7, 3.3, and 4 mm in the RL, SI, and AP directions, respectively. An offline correction protocol combined with an online correction protocol in the first four fractions reduced random errors further to 0.9, 1.1, and 1.0 mm in the RL, SI, and AP directions, respectively. A daily online protocol reduced all errors to <1 mm. Intrafraction motion had greater impact on the effectiveness of the online protocol than the offline protocols.An offline protocol using gold markers is effective in reducing the systematic error. The value of online protocols is reduced by intrafraction motion.

Image guided adaptive radiation therapy offers individualized solutions to improve target coverage and reduce normal tissue irradiation, allowing the opportunity to increase the radiation tumor dose and spare normal bladder tissue.A library of 3 intensity modulated radiation therapy plans were created (small, medium, and large) from planning computed tomography (CT) scans performed at 30 and 60 minutes; treating the whole bladder to 52 Gy and the tumor to 70 Gy in 32 fractions. A "plan of the day" approach was used for treatment delivery. A post-treatment cone beam CT (CBCT) scan was acquired weekly to assess intrafraction filling and coverage.A total of 18 patients completed treatment to 70 Gy. The plan and treatment for 1 patient was to 68 Gy. Also, 1 patient's plan was to 70 Gy but the patient was treated to a total dose of 65.6 Gy because dose-limiting toxicity occurred before dose escalation. A total of 734 CBCT scans were evaluated. Small, medium, and large plans were used in 36%, 48%, and 16% of cases, respectively. The mean ± standard deviation rate of intrafraction filling at the start of treatment (ie, week 1) was 4.0 ± 4.8 mL/min (range 0.1-19.4) and at end of radiation therapy (ie, week 5 or 6) was 1.1 ± 1.6 mL/min (range 0.01-7.5; P=.002). The mean D98 (dose received by 98% volume) of the tumor boost and bladder as assessed on the post-treatment CBCT scan was 97.07% ± 2.10% (range 89.0%-104%) and 99.97% ± 2.62% (range 96.4%-112.0%). At a median follow-up period of 19 months (range 4-33), no muscle-invasive recurrences had developed. Two patients experienced late toxicity (both grade 3 cystitis) at 5.3 months (now resolved) and 18 months after radiation therapy.Image guided adaptive radiation therapy using intensity modulated radiation therapy to deliver a simultaneous integrated tumor boost to 70 Gy is feasible, with acceptable toxicity, and will be evaluated in a randomized trial.

Therapeutic radiotherapy is an important treatment of pelvic cancers. Historically, low-fiber diets have been recommended despite a lack of evidence and potentially beneficial mechanisms of fiber. This randomized controlled trial compared low-, habitual-, and high-fiber diets for the prevention of gastrointestinal toxicity in patients undergoing pelvic radiotherapy. Patients were randomly assigned to low-fiber [≤10 g nonstarch polysaccharide (NSP)/d], habitual-fiber (control), or high-fiber (≥18 g NSP/d) diets and received individualized counseling at the start of radiotherapy to achieve these targets. The primary endpoint was the difference between groups in the change in the Inflammatory Bowel Disease Questionnaire–Bowel Subset (IBDQ-B) score between the starting and nadir (worst) score during treatment. Other measures included macronutrient intake, stool diaries, and fecal short-chain fatty acid concentrations. Patients were randomly assigned to low-fiber (n = 55), habitual-fiber (n = 55), or high-fiber (n = 56) dietary advice. Fiber intakes were significantly different between groups (P < 0.001). The difference between groups in the change in IBDQ-B scores between the start and nadir was not significant (P = 0.093). However, the change in score between the start and end of radiotherapy was smaller in the high-fiber group (mean ± SD: −3.7 ± 12.8) than in the habitual-fiber group (−10.8 ± 13.5; P = 0.011). At 1-y postradiotherapy (n = 126) the difference in IBDQ-B scores between the high-fiber (+0.1 ± 14.5) and the habitual-fiber (−8.4 ± 13.3) groups was significant (P = 0.004). No significant differences were observed in stool frequency or form or in short-chain fatty acid concentrations. Significant reductions in energy, protein, and fat intake occurred in the low- and habitual-fiber groups only. Dietary advice to follow a high-fiber diet during pelvic radiotherapy resulted in reduced gastrointestinal toxicity both acutely and at 1 y compared with habitual-fiber intake. Restrictive, non–evidence-based advice to reduce fiber intake in this setting should be abandoned. This trial was registered at clinicaltrials.gov as NCT 01170299.

<h3>Purpose and Objectives</h3> We report on the clinical outcomes of a phase 2 study assessing image guided hypofractionated weekly radiation therapy in bladder cancer patients unsuitable for radical treatment. <h3>Methods and Materials</h3> Fifty-five patients with T2-T4aNx-2M0-1 bladder cancer not suitable for cystectomy or daily radiation therapy treatment were recruited. A "plan of the day" radiation therapy approach was used, treating the whole (empty) bladder to 36 Gy in 6 weekly fractions. Acute toxicity was assessed weekly during radiation therapy, at 6 and 12 weeks using the Common Terminology Criteria for Adverse Events version 3.0. Late toxicity was assessed at 6 months and 12 months using Radiation Therapy Oncology Group grading. Cystoscopy was used to assess local control at 3 months. Cumulative incidence function was used to determine local progression at 1 at 2 years. Death without local progression was treated as a competing risk. Overall survival was estimated using the Kaplan-Meier method. <h3>Results</h3> Median age was 86 years (range, 68-97 years). Eighty-seven percent of patients completed their prescribed course of radiation therapy. Genitourinary and gastrointestinal grade 3 acute toxicity was seen in 18% (10/55) and 4% (2/55) of patients, respectively. No grade 4 genitourinary or gastrointestinal toxicity was seen. Grade ≥3 late toxicity (any) at 6 and 12 months was seen in 6.5% (2/31) and 4.3% (1/23) of patients, respectively. Local control after radiation therapy was 92% of assessed patients (60% total population). Cumulative incidence of local progression at 1 year and 2 years for all patients was 7% (95% confidence interval [CI] 2%-17%) and 17% (95% CI 8%-29%), respectively. Overall survival at 1 year was 63% (95% CI 48%-74%). <h3>Conclusion</h3> Hypofractionated radiation therapy delivered weekly with a plan of the day approach offers good local control with acceptable toxicity in a patient population not suitable for radical bladder treatment.

Aims To evaluate the feasibility and heart-sparing ability of the voluntary breath-hold (VBH) technique in a multicentre setting. Materials and methods Patients were recruited from 10 UK centres. Following surgery for early left breast cancer, patients with any heart inside the 50% isodose from a standard free-breathing tangential field treatment plan underwent a second planning computed tomography (CT) scan using the VBH technique. A separate treatment plan was prepared on the VBH CT scan and used for treatment. The mean heart, left anterior descending coronary artery (LAD) and lung doses were calculated. Daily electronic portal imaging (EPI) was carried out and scanning/treatment times were recorded. The primary end point was the percentage of patients achieving a reduction in mean heart dose with VBH. Population systematic (Σ) and random errors (σ) were estimated. Within-patient comparisons between techniques used Wilcoxon signed-rank tests. Results In total, 101 patients were recruited during 2014. Primary end point data were available for 93 patients, 88 (95%) of whom achieved a reduction in mean heart dose with VBH. Mean cardiac doses (Gy) for free-breathing and VBH techniques, respectively, were: heart 1.8 and 1.1, LAD 12.1 and 5.4, maximum LAD 35.4 and 24.1 (all P<0.001). Population EPI-based displacement data showed Σ =+1.3–1.9 mm and σ=1.4–1.8 mm. Median CT and treatment session times were 21 and 22 min, respectively. Conclusions The VBH technique is confirmed as effective in sparing heart tissue and is feasible in a multicentre setting.

Online MRI guided adaptive radiotherapy (MRIgRT) is resource intensive. To maintain and increase uptake traditional roles and responsibilities may need refining. This novel study aims to provide an in-depth understanding and subsequent impact of the roles required to deliver on-line adaptive MRIgRT by exploring the current skills and knowledge of radiographers.A purposive sampling approach was used to invite radiographers, clinicians and physicists from centres with experience of MRIgRT to participate. Focus Group Interviews were conducted with two facilitators using a semi-structure interview guide (Appendix 1). Four researchers independently familiarised themselves and coded the data using framework analysis. A consensus thematic framework of ptive Radiotherapy codes and categories was agreed and systematically applied.Thirty participants took part (Radiographers: N = 18, Physicists: N = 9 and Clinicians: N = 3). Three key themes were identified: 'Current MRIgRT', 'Training' and 'Future Practice'. Current MRIgRT identified a variation in radiographers' roles and responsibilities with pathways ranging from radiographer-led, clinician-light-led and MDT-led. The consensus was to move towards radiographer-led with the need to have a robust on-call service heavily emphasised. Training highlighted the breadth of knowledge required by radiographers including MRI, contouring, planning and dosimetry, and treatment experience. Debate was presented over timing and length of training required. Future Practice identified the need to have radiographers solely deliver MRIgRT, to reduce staff present which was seen as a main driver, and time and resources to train radiographers seen as the main barriers.Radiographer-led MRIgRT is an exciting development because of the potential radiographer role development. A national training framework created collaboratively with all stakeholders and professions involved would ensure consistency in skills and knowledge.Role development and changes in education for therapeutic radiographers.

Hybrid magnetic resonance (MR)-guided linear accelerators represent a new horizon in the field of radiation oncology. By harnessing the favorable combination of on-board MR-imaging with the possibility to daily recalculate the treatment plan based on real-time anatomy, the accuracy in target and organs-at-risk identification is expected to be improved, with the aim to provide the best tailored treatment. To date, two main MR-linac hybrid machines are available, Elekta Unity and Viewray MRIdian. Of note, compared to conventional linacs, these devices raise practical issues due to the positioning phase for the need to include the coil in the immobilization procedure and in order to perform the best reproducible positioning, also in light of the potentially longer treatment time. Given the relative novelty of this technology, there are few literature data regarding the procedures and the workflows for patient positioning and immobilization for MR-guided daily adaptive radiotherapy. In the present narrative review, we resume the currently available literature and provide an overview of the positioning and setup procedures for all the anatomical districts for hybrid MR-linac systems.

Hypofractionated radiation therapy can be used to treat patients with muscle-invasive bladder cancer unable to have radical therapy. Toxicity is a key concern, but adaptive plan-of the day (POD) image-guided radiation therapy delivery could improve outcomes by minimizing the volume of normal tissue irradiated. The HYBRID trial assessed the multicenter implementation, safety, and efficacy of this strategy.HYBRID is a Phase II randomized trial that was conducted at 14 UK hospitals. Patients with T2-T4aN0M0 muscle-invasive bladder cancer unsuitable for radical therapy received 36 Gy in 6 weekly fractions, randomized (1:1) to standard planning (SP) or adaptive planning (AP) using a minimization algorithm. For AP, a pretreatment cone beam computed tomography (CT) was used to select the POD from 3 plans (small, medium, and large). Follow-up included standard cystoscopic, radiologic, and clinical assessments. The primary endpoint was nongenitourinary Common Terminology Criteria for Adverse Events (CTCAE) grade ≥ 3 (≥G3) toxicity within 3 months of radiation therapy. A noncomparative single stage design aimed to exclude ≥30% toxicity rate in each planning group in patients who received ≥1 fraction of radiation therapy. Local control at 3-months (both groups combined) was a key secondary endpoint.Between April 15, 2014, and August 10, 2016, 65 patients were enrolled (SP, n = 32; AP, n = 33). The median follow-up time was 38.8 months (interquartile range [IQR], 36.8-51.3). The median age was 85 years (IQR, 81-89); 68% of participants (44 of 65) were male; and 98% of participants had grade 3 urothelial cancer. In 63 evaluable participants, CTCAE ≥G3 nongenitourinary toxicity rates were 6% (2 of 33; 95% confidence interval [CI], 0.7%-20.2%) for the AP group and 13% (4 of 30; 95% CI, 3.8%-30.7%) for the SP group. Disease was present in 9/48 participants assessed at 3 months, giving a local control rate of 81.3% (95% CI, 67.4%-91.1%).POD adaptive radiation therapy was successfully implemented across multiple centers. Weekly ultrahypofractionated 36 Gy/6 fraction radiation therapy is safe and provides good local control rates in this older patient population.

Advances in Radiotherapy (RT) technology and increase of complexity in cancer care have enabled the implementation of new treatment techniques. Subsequently, a greater level of autonomy, responsibility, and accountability in the practice of Therapeutic Radiographers/Radiation Therapists (TR/RTTs) has led to Advanced Practice (AP) roles. The published evidence of this role is scattered with confusing terminology and divergence regarding the perception of whether a specific role represents AP internationally. This study aims to establish an international baseline of evidence on AP roles in RT to identify roles and activities performed by TR/RTTs at advanced level practice and to summarise the impact.A systematic PRISMA review of the literature was undertaken. Thematic analysis was used to synthesise the roles and associated activities. Six RT external experts validated the list. The impact was scrutinised in terms of clinical, organisational, and professional outcomes.Studies (n = 87) were included and categorised into four groups. AP roles were listed by clinical area, site-specific, and scope of practice, and advanced activities were organised into seven dimensions and 27 sub-dimensions. Three most-reported outcomes were: enhanced service capacity, higher patient satisfaction, and safety maintenance.Evidence-based AP amongst TR/RTTs show how AP roles were conceptualised, implemented, and evaluated. Congruence studies have shown that TR/RTTs are at par with the gold-standard across the various AP roles.This is the first systematic literature review synthetisising AP roles and activities of TR/RTTs. This study also identified the main areas of AP that can be used to develop professional frameworks and education guiding policy by professional bodies, educators and other stakeholders.

On target: ensuring geometric accuracy in radiotherapy was published in 2008 and aimed to provide guidelines for image-guided radiotherapy (IGRT) [1]. At the time of publication, electronic portal imaging (EPI) was the most common imaging technology available, the implementation and use of which had increased over the previous decade. Although EPI enabled images to be acquired immediately before radiotherapy delivery, the most common correction protocols used were offline [2,3]. This was often driven by the lack of integrated couch and imaging systems; moving the couch manually increased both treatment time and the potential for error by interrupting the treatment workflow.

Volumetric modulated arc therapy (VMAT) is a radiotherapy technique in which the gantry rotates while the beam is on. Gantry speed, multileaf collimator (MLC) leaf position and dose rate vary continuously during the irradiation. For optimum results, this type of treatment should be subject to image guidance. The application of VMAT and image guidance to the treatment of a lung cancer patient is described.In-house software AutoBeam was developed to facilitate treatment planning for VMAT beams. The algorithm consisted of a fluence optimisation using the iterative least-squares technique, a segmentation and then a direct-aperture optimisation. A dose of 50 Gy in 25 fractions was planned, using a single arc with 35 control points at 10 degrees intervals. The resulting plan was transferred to a commercial treatment planning system for final calculation. The plan was verified using a 0.6 cm(3) ionisation chamber and film in a rectangular phantom. The patient was treated supine on a customised lung board and imaged daily with cone-beam CT for the first three days then weekly thereafter.The VMAT plan provided slightly improved coverage of the planning target volume (PTV) and slightly lower volume of lung irradiated to 20 Gy (V(20)) than a three-field conformal plan (PTV minimum dose 85.0 Gy vs. 81.8 Gy and lung V(20) 31.5% vs. 34.8%). The difference between the measured and planned dose was -1.1% (measured dose lower) and 97.6% of the film passed a gamma test of 3% and 3mm. The VMAT treatment required 90 s for delivery of a single fraction of 2 Gy instead of 180 s total treatment time for the conformal plan.VMAT provides a quality dose distribution with a short treatment time as shown in an example of a lung tumour. The technique should allow for more efficient delivery of high dose treatments, such as used for hypofractionated radiotherapy of small volume lung tumours, and the technique may also be used in conjunction with Active Breathing Control, where fewer breath holds will be required.

To assess feasibility and reproducibility of an Active Breathing Coordinator (ABC) used throughout radical radiotherapy for non-small-cell lung cancer, and compare lung dosimetric parameters between free-breathing and ABC plans.A total of 18 patients, recruited into an approved study, had free-breathing and ABC breath-hold treatment plans generated. Lung volume, the percentage volume of lung treated to a dose of ≥20 Gy (V(20)), and mean lung dose (MLD) were compared. Treatment (64 Gy in 32 fractions, 5 days/week) was delivered in breath-hold. Repeat breath-hold computed tomography scans were used to assess change in gross tumor volume (GTV) size and position. Setup error was also measured and potential GTV-planning target volume (PTV) margins calculated.Seventeen of 18 patients completed radiotherapy using ABC daily. Intrafraction tumor position was consistent, but interfraction variation had mean (range) values of 5.1 (0-25), 3.6 (0-9.7), and 3.5 (0-16.6) mm in the superoinferior (SI), right-left (RL), and anteroposterior (AP) directions, respectively. Tumor moved partially outside the PTV in 5 patients. Mean reduction in GTV from planning to end of treatment was 25% (p = 0.003). Potentially required PTV margins were 18.1, 11.9, and 11.9 mm in SI, RL, and AP directions. ABC reduced V(20) by 13% (p = 0.0001), V(13) by 12% (p = 0.001), and MLD by 13% (p < 0.001) compared with free-breathing; lung volume increased by 41% (p < 0.001).Clinically significant movements of GTV were seen during radiotherapy for non-small-cell lung cancer using ABC. Image guidance is recommended with ABC. The use of ABC can reduce dose volume parameters determining lung toxicity, and might allow for equitoxic radiotherapy dose escalation.

Computer controlled breath-hold effectively reduces organ motion for image-guided precision radiotherapy of lung tumors. However, the acquisition time of 3D cone-beam-CT (CBCT) exceeds maximum breath-hold times. We have developed an approach enabling online verification using CBCT image acquisition with ABC®-based breath-hold.Patient CBCT images were acquired with ABC®-based repeat breath-hold. The clinical situation was also simulated with a Motion Phantom. Reconstruction of patient and phantom images with selection of free-breathing and breath-hold projections only was performed.CBCT-imaging in repeat breath-hold resulted in a precisely spherical appearance of a tumor-mimicking structure in the phantom. A faint "ghost" structure (free-breathing phases) can be clearly discriminated. Mean percentage of patient breath-hold time was 66%. Reconstruction based on free-breathing-only shows blurring of both tumor and diaphragm, reconstruction based on breath-hold projections only resulted in sharp contours of the same structures. From the phantom experiments, a maximal repositioning error of 1mm in each direction can be estimated.CBCT during repetitive breath hold provides reliable soft-tissue-based positioning. Fast 3D-imaging during one breath-hold is currently under development and has the potential to accelerate clinical linac-based volume imaging.

While the importance of a consistent rectal volume during radiation therapy planning and treatment for patients receiving radiation therapy to the prostate is recognized, there is no clear guidance as to the most effective method. This review examines the evidence for the efficacy of rectal preparations. Eighteen papers were found where the primary aim was to investigate a rectal emptying intervention and included 5 different strategies. These included evacuation techniques, dietary interventions, laxatives, and enemas and were either investigated alone or in combination. There is no robust evidence to recommend one rectal emptying strategy over another. Further investigation in adequately powered clinical trials is advised.

Breath-holding techniques reduce the amount of radiation received by cardiac structures during tangential-field left breast radiotherapy. With these techniques, patients hold their breath while radiotherapy is delivered, pushing the heart down and away from the radiotherapy field. Despite clear dosimetric benefits, these techniques are not yet in widespread use. One reason for this is that commercially available solutions require specialist equipment, necessitating not only significant capital investment, but often also incurring ongoing costs such as a need for daily disposable mouthpieces. The voluntary breath-hold technique described here does not require any additional specialist equipment. All breath-holding techniques require a surrogate to monitor breath-hold consistency and whether breath-hold is maintained. Voluntary breath-hold uses the distance moved by the anterior and lateral reference marks (tattoos) away from the treatment room lasers in breath-hold to monitor consistency at CT-planning and treatment setup. Light fields are then used to monitor breath-hold consistency prior to and during radiotherapy delivery.

The implementation of plan of the day selection for patients receiving radiotherapy (RT) for bladder cancer requires efficient and confident decision-making. This article describes the development of a training programme and maintenance of competency.Cone beam CT (CBCT) images acquired on patients receiving RT for bladder cancer were assessed to establish baseline competency and training needs. A training programme was implemented, and observers were asked to select planning target volumes (PTVs) on two groups of 20 patients' images. After clinical implementation, the PTVs chosen were reviewed offline, and an audit performed after 3 years.A mean of 73% (range, 53-93%) concordance rate was achieved prior to training. Subsequent to training, the mean score decreased to 66% (Round 1), then increased to 76% (Round 2). Six radiographers and two clinicians successfully completed the training programme. An independent observer reviewed the images offline after clinical implementation, and a 91% (126/139) concordance rate was achieved. During the audit, 125 CBCT images from 13 patients were reviewed by a single observer and concordance was 92%.Radiographer-led selection of plan of the day was implemented successfully with the use of a training programme and continual assessment. Quality has been maintained over a period of 3 years.The training programme was successful in achieving and maintaining competency for a plan of the day technique.

<h3>Purpose</h3> To investigate the feasibility of dose escalation and hypofractionation of pelvic lymph node intensity modulated radiation therapy (PLN-IMRT) in prostate cancer (PCa). <h3>Methods and Materials</h3> In a phase 1/2 study, patients with advanced localized PCa were sequentially treated with 70 to 74 Gy to the prostate and dose-escalating PLN-IMRT at doses of 50 Gy (cohort 1), 55 Gy (cohort 2), and 60 Gy (cohort 3) in 35 to 37 fractions. Two hypofractionated cohorts received 60 Gy to the prostate and 47 Gy to PLN in 20 fractions over 4 weeks (cohort 4) and 5 weeks (cohort 5). All patients received long-course androgen deprivation therapy. Primary outcome was late Radiation Therapy Oncology Group toxicity at 2 years after radiation therapy for all cohorts. Secondary outcomes were acute and late toxicity using other clinician/patient-reported instruments and treatment efficacy. <h3>Results</h3> Between August 9, 2000, and June 9, 2010, 447 patients were enrolled. Median follow-up was 90 months. The 2-year rates of grade 2+ bowel/bladder toxicity were as follows: cohort 1, 8.3%/4.2% (95% confidence interval 2.2%-29.4%/0.6%-26.1%); cohort 2, 8.9%/5.9% (4.1%-18.7%/2.3%-15.0%); cohort 3, 13.2%/2.9% (8.6%-20.2%/1.1%-7.7%); cohort 4, 16.4%/4.8% (9.2%-28.4%/1.6%-14.3%); cohort 5, 12.2%/7.3% (7.6%-19.5%/3.9%-13.6%). Prevalence of bowel and bladder toxicity seemed to be stable over time. Other scales mirrored these results. The biochemical/clinical failure–free rate was 71% (66%-75%) at 5 years for the whole group, with pelvic lymph node control in 94% of patients. <h3>Conclusions</h3> This study shows the safety and tolerability of PLN-IMRT. Ongoing and planned phase 3 studies will need to demonstrate an increase in efficacy using PLN-IMRT to offset the small increase in bowel side effects compared with prostate-only IMRT.

<h3>Purpose</h3> Our purpose was to perform an in vivo validation of ultrasound imaging for intrafraction motion estimation using the Elekta Clarity Autoscan system during prostate radiation therapy. The study was conducted as part of the Clarity-Pro trial (NCT02388308). <h3>Methods and Materials</h3> Initial locations of intraprostatic fiducial markers were identified from cone beam computed tomography scans. Marker positions were translated according to Clarity intrafraction 3-dimensional prostate motion estimates. The updated locations were projected onto the 2-dimensional electronic portal imager plane. These Clarity-based estimates were compared with the actual portal-imaged 2-dimensional marker positions. Images from 16 patients encompassing 80 fractions were analyzed. To investigate the influence of intraprostatic markers and image quality on ultrasound motion estimation, 3 observers rated image quality, and the marker visibility on ultrasound images was assessed. <h3>Results</h3> The median difference between Clarity-defined intrafraction marker locations and portal-imaged marker locations was 0.6 mm (with 95% limit of agreement at 2.5 mm). Markers were identified on ultrasound in only 3 of a possible 240 instances. No linear relationship between image quality and Clarity motion estimation confidence was identified. The difference between Clarity-based motion estimates and electronic portal–imaged marker location was also independent of image quality. Clarity estimation confidence was degraded in a single fraction owing to poor probe placement. <h3>Conclusions</h3> The accuracy of Clarity intrafraction prostate motion estimation is comparable with that of other motion-monitoring systems in radiation therapy. The effect of fiducial markers in the study was deemed negligible as they were rarely visible on ultrasound images compared with intrinsic anatomic features. Clarity motion estimation confidence was robust to variations in image quality and the number of ultrasound-imaged anatomic features; however, it was degraded as a result of poor probe placement.

Objective: The purpose of this UK study was to evaluate interfraction reproducibility and body image score when using ultraviolet (UV) tattoos (not visible in ambient lighting) for external references during breast/chest wall radiotherapy and compare with conventional dark ink. Methods: In this non-blinded, single-centre, parallel group, randomized control trial, patients were allocated to receive either conventional dark ink or UV ink tattoos using computer-generated random blocks. Participant assignment was not masked. Systematic (∑) and random (σ) setup errors were determined using electronic portal images. Body image questionnaires were completed at pre-treatment, 1 month and 6 months to determine the impact of tattoo type on body image. The primary end point was to determine that UV tattoo random error (σsetup) was no less accurate than with conventional dark ink tattoos, i.e. <2.8 mm. Results: 46 patients were randomized to receive conventional dark or UV ink tattoos. 45 patients completed treatment (UV: n = 23, dark: n = 22). σsetup for the UV tattoo group was <2.8 mm in the u and v directions (p = 0.001 and p = 0.009, respectively). A larger proportion of patients reported improvement in body image score in the UV tattoo group compared with the dark ink group at 1 month [56% (13/23) vs 14% (3/22), respectively] and 6 months [52% (11/21) vs 38% (8/21), respectively]. Conclusion: UV tattoos were associated with interfraction setup reproducibility comparable with conventional dark ink. Patients reported a more favourable change in body image score up to 6 months following treatment. Advances in knowledge: This study is the first to evaluate UV tattoo external references in a randomized control trial.

Whole bladder magnetic resonance image-guided radiotherapy using the 1.5 Telsa MR-linac is feasible. Full online adaptive planning workflow based on the anatomy seen at each fraction was performed. This was delivered within 45 min. Intra-fraction bladder filling did not compromise target coverage. Patients reported acceptable tolerance of treatment.

Two systems have been developed for treating patients with locally advanced prostate cancer using intensity-modulated radiotherapy (IMRT): one using dynamic multi-leaf collimator delivery and the other using step-and-shoot. This paper describes the clinical implementation of these two techniques, and presents results from the first 14 patients treated in a clinical setting (nine dynamic, five step-and-shoot).Dynamic treatments were planned using Corvus, and step-and-shoot using Helax-TMS; all were delivered using Elekta accelerators. Prior to the first clinical treatments, validation measurements were carried out for each system, including measurements for a complete IMRT treatment. The reproducibility of dynamic delivery and the characteristics of the accelerator for low-monitor-unit (MU) deliveries were also assessed. An extensive quality assurance (QA) program was performed for each of the patients. Additionally, timing measurements were carried out to assess the practicalities of the technique.The planning objectives were met in most cases. Absolute doses for complete IMRT treatments were within 2%, on average, with dose distributions generally showing agreement within 3% or 3 mm. Beam modulation measurements made throughout each patient's treatment indicated that both delivery methods were reproducible. The dynamic plans required an average of 765 MU per beam, with a treatment delivery time of 14 min; corresponding results for step-and-shoot plans were 105 MU and 10 min.Two IMRT techniques for this group of patients have been successfully implemented in the clinic. The more complex dynamic treatments showed no advantages over the step-and-shoot approach. QA results have shown accurate and reproducible delivery for both techniques, giving increased confidence in the techniques and allowing a reduction in the QA program.

Purpose: This study assesses the accuracy of NOMOS B-mode acquisition and targeting system (BAT) compared with computed tomography (CT) in localizing the prostate. Methods and Materials: Twenty-six patients were CT scanned, and the prostate was localized by 3 observers using the BAT system. The BAT couch shift measurements were compared with the CT localization. Six of the patients had gold markers present in the prostate, and the prostate movement determined by BAT was compared with the movement determined by the gold markers. Results: Using the BAT system, the 3 observers determined the prostate position to be a mean of 1–5 mm over all directions with respect to the CT. The proportion of readings with a difference >3 mm between the observers was in the range of 25% to 44%. The prostate movement based on gold markers was an average of 3–5 mm different from that measured by BAT. The literature assessing the accuracy and reproducibility on BAT is summarized and compared with our findings. Conclusions: We have found that there are systematic differences between the BAT-defined prostate position compared with that estimated on CT using gold grain marker seeds. Purpose: This study assesses the accuracy of NOMOS B-mode acquisition and targeting system (BAT) compared with computed tomography (CT) in localizing the prostate. Methods and Materials: Twenty-six patients were CT scanned, and the prostate was localized by 3 observers using the BAT system. The BAT couch shift measurements were compared with the CT localization. Six of the patients had gold markers present in the prostate, and the prostate movement determined by BAT was compared with the movement determined by the gold markers. Results: Using the BAT system, the 3 observers determined the prostate position to be a mean of 1–5 mm over all directions with respect to the CT. The proportion of readings with a difference >3 mm between the observers was in the range of 25% to 44%. The prostate movement based on gold markers was an average of 3–5 mm different from that measured by BAT. The literature assessing the accuracy and reproducibility on BAT is summarized and compared with our findings. Conclusions: We have found that there are systematic differences between the BAT-defined prostate position compared with that estimated on CT using gold grain marker seeds.

Intensity modulated radiotherapy (IMRT) allows the delivery of higher and more homogeneous radiation dose to head and neck tumours. This study aims to determine the safety of dose-escalated chemo-IMRT for larynx preservation in locally advanced head and neck cancer.Patients with T2-4, N1-3, M0 squamous cell carcinoma of the larynx or hypopharynx were treated with a simultaneous-boost IMRT. Two radiation dose levels (DL) were tested: In DL 1, 63 Gy/28F was delivered to primary tumour and involved nodes and 51.8 Gy/28F to elective nodes. In DL 2, the doses were 67.2 Gy/28F and 56 Gy/28F, respectively, representing a 9% dose escalation for the primary. All patients received 2 cycles of neoadjuvant cisplatin and 5-fluorouracil, and concomitant cisplatin. Acute (NCICTCv.2.0) and late toxicity (RTOG and modified LENTSOM) were collected.Thirty patients were entered, 15 in each dose level. All patients completed the treatment schedule. In DL 1, the incidences of acute G3 toxicities were 27% (pain), 20% (radiation dermatitis), 0% (xerostomia) and 67% required gastrostomy tubes. For DL 2 the corresponding incidences were 40%, 20%, 7%, and 87%. G3 dysphagia and pain persisted longer in DL 2. With regard to mucositis, a prolonged healing time for DL 2 was found, with prevalence of G2 of 58% in week 10. No acute grade 4 toxicity was observed. At 6 months, 1 patient in DL 2 had G3 late toxicity (dysphagia). No dose limiting toxicity was found. Complete response rates were 80% in DL 1, and 87% in DL 2.Moderately accelerated chemo-IMRT is safe and feasible with good compliance and acceptable acute toxicity. Dose escalation was possible without a significant difference in acute toxicity. Longer follow-up is required to determine the incidence of late radiation toxicities, and tumour control rates.

The prognosis from non-small cell lung cancer remains poor, even in those patients suitable for radical radiotherapy. The ability of radiotherapy to achieve local control is hampered by the sensitivity of normal structures to irradiation at the high tumour doses needed. This study aimed to look at the potential gain in tumour control probability from dose escalation facilitated by moderate deep inspiration breath-hold.The data from 28 patients, recruited into two separate studies were used. These patients underwent planning with and without the use of moderate deep inspiration breath-hold with an active breathing control (ABC) device. Whilst maintaining the mean lung dose (MLD) at the level of the conventional plan, the ABC plan dose was theoretically escalated to a maximum of 84 Gy, constrained by usual normal tissue tolerances. Calculations were performed using data for both lungs and for the ipsilateral lung only. Resulting local progression-free survival at 30 months was calculated using a standard logistic model.The prescription dose could be escalated from 64 Gy to a mean of 73.7+/-6.5 Gy without margin reduction, which represents a statistically significant increase in tumour control probability from 0.15+/-0.01 to 0.29+/-0.11 (p<0.0001). The results were not statistically different whether both lungs or just the ipsilateral lung was used for calculations.A near-doubling of tumour control probability is possible with modest dose escalation, which can be achieved with no extra increase in lung dose if deep inspiration breath-hold techniques are used.

Pelvic irradiation in addition to prostate irradiation may improve outcome in locally advanced prostate cancer, but is associated with dose-limiting bowel toxicity. We report the preliminary results of a dose escalation study using intensity-modulated radiotherapy.Eligible patients had high-risk (T3, Gleason > or =8 or prostate-specific antigen > or =20 ng/ml) or lymph node-positive disease. Intensity-modulated radiotherapy was inverse planned giving 70 Gy/35 fractions to the prostate and 50 Gy/55 Gy/60 Gy in sequential cohorts to the pelvis with a 5 Gy boost to positive lymph nodes. Acute and late toxicity were recorded with Radiation Therapy Oncology Group (RTOG) and Late Effects Normal Tissue - Subjective Objective Management LENT-SOM scales. Neoadjuvant androgen suppression was given for 3 years. This report concerns the 50 and 55 Gy cohorts.Seventy-nine men were recruited (25 to 50 Gy/54 to 55 Gy) with a median follow-up of 2 years. Patients were divided into two groups according to the total bowel volume outlined (median 450 cm(3)). Acute RTOG (> or =2) bowel toxicity was 40 and 50% for the 50 and 55 Gy groups and 38 and 51% for bowel volume <450 cm(3) and > or =450 cm(3), respectively, suggesting both volume and dose relationships for acute effects. Late RTOG diarrhoea > or =grade 2 was only seen with bowel volume > or =450 cm(3), but no dose effect was apparent (12%/50 Gy and 10%/55 Gy). LENT-SOM bowel > or =grade 2 toxicity occurred in 22%/50 Gy and 15%/55 Gy. Only one patient had grade 3 toxicity. A dose volume histogram analysis showed increased late RTOG diarrhoea > or =grade 2 with larger bowel volume irradiated, significant for BV40 >124 cm(3) (P=0.04), BV45 >71 cm(3) (P=0.03) and BV60 >2 cm(3) (P=0.01).Acute and late bowel toxicity was acceptably low using a pelvic dose of up to 55 Gy over 7 weeks. Both relate to total pelvic bowel volume and dose volume constraints have been defined.

Purpose To compare kV computed tomography (CBCT) with electronic portal imaging (EPI) and evaluate set-up variations in the anterior–posterior (AP), right–left (LR) and cranio-caudal (CC) directions and rotational variations: pitch, roll, and yaw, for oesophageal cancer patients treated with radical radiotherapy. Methods and materials Twenty patients with locally advanced oesophageal cancer treated with chemoradiation were consented for this prospective ethics approved protocol. Patients were positioned using skin marks/tattoos, kV-CBCT scans (XVI) and EPI’s were performed prior to treatment and registered to the planning CT scans and digitally reconstructed radiographs, respectively. XVI data was used to adjust patient setups before treatment delivery. A total of 122 EPI pairs and 207 CBCT scans were analysed. The systematic and random errors were calculated. Results The systematic and random errors (mm) for XVI were 1.3, 1.7, 1.4 and 2.6, 3.9, 2.0 in RL, CC and AP direction, respectively, with EPI of similar magnitude. There was no correlation between the 2 modalities of imaging as 31.7% of all image pairs were discordant >3 mm and 12.5% >5 mm. XVI identified rotations >3° in 44 images. Conclusions EPI results in different position correction for verification of radiotherapy in oesophageal malignancies when compared with CBCT. CBCT verification offers adequate 3D volumetric image quality to improve the accuracy of treatment delivery for oesophageal malignancies in radiotherapy and should be used for image guidance.

Purpose There has been no previously published data related to the quantification of rectal motion using cone-beam computed tomography (CBCT) during standard conformal long-course chemoradiotherapy. The purpose of the present study was to quantify the interfractional changes in rectal movement and dimensions and rectal and bladder volume using CBCT and to quantify the bony anatomy displacements to calculate the margins required to account for systematic (Σ) and random (σ) setup errors. Methods and Materials CBCT images were acquired from 16 patients on the first 3 days of treatment and weekly thereafter. The rectum and bladder were outlined on all CBCT images. The interfraction movement was measured using fixed bony landmarks as references to define the rectal location (upper, mid, and low), The maximal rectal diameter at the three rectal locations was also measured. The bony anatomy displacements were quantified, allowing the calculation of systematic (Σ) and random (σ) setup errors. Results A total of 123 CBCT data sets were analyzed. Analysis of variance for standard deviation from planning scans showed that rectal anterior and lateral wall movement differed significantly by rectal location. Anterior and lateral rectal wall movements were larger in the mid and upper rectum compared with the low rectum. The posterior rectal wall movement did not change significantly with the rectal location. The rectal diameter changed more in the mid and upper than in the low rectum. No consistent relationship was found between the rectal and bladder volume and time, nor was a significant relationship found between the rectal volume and bladder volume. Conclusions In the present study, the anterior and lateral rectal movement and rectal diameter were found to change most in the upper rectum, followed by the mid rectum, with the smallest changes seen in the low rectum. Asymmetric margins are warranted to ensure phase 2 coverage. There has been no previously published data related to the quantification of rectal motion using cone-beam computed tomography (CBCT) during standard conformal long-course chemoradiotherapy. The purpose of the present study was to quantify the interfractional changes in rectal movement and dimensions and rectal and bladder volume using CBCT and to quantify the bony anatomy displacements to calculate the margins required to account for systematic (Σ) and random (σ) setup errors. CBCT images were acquired from 16 patients on the first 3 days of treatment and weekly thereafter. The rectum and bladder were outlined on all CBCT images. The interfraction movement was measured using fixed bony landmarks as references to define the rectal location (upper, mid, and low), The maximal rectal diameter at the three rectal locations was also measured. The bony anatomy displacements were quantified, allowing the calculation of systematic (Σ) and random (σ) setup errors. A total of 123 CBCT data sets were analyzed. Analysis of variance for standard deviation from planning scans showed that rectal anterior and lateral wall movement differed significantly by rectal location. Anterior and lateral rectal wall movements were larger in the mid and upper rectum compared with the low rectum. The posterior rectal wall movement did not change significantly with the rectal location. The rectal diameter changed more in the mid and upper than in the low rectum. No consistent relationship was found between the rectal and bladder volume and time, nor was a significant relationship found between the rectal volume and bladder volume. In the present study, the anterior and lateral rectal movement and rectal diameter were found to change most in the upper rectum, followed by the mid rectum, with the smallest changes seen in the low rectum. Asymmetric margins are warranted to ensure phase 2 coverage.

The potential advantages of stereotactic body radiotherapy (SBRT) for early stage non-small cell lung cancer (NSCLC) over conventional fractionated radiotherapy include a higher biological effective dose, a reduction in accelerated repopulation, greater patient convenience and reduced demand on radiotherapy resources. Before introducing SBRT in our department, a review of planning and delivery was undertaken, starting with an assessment of optimum beam number and arrangement.Radiotherapy planning computed tomography scans for five patients previously treated for T1 peripheral NSCLC were selected. In each the contoured tumour had planning target volume (PTV) margins of 1cm in all directions. Forward-planned three-field coplanar and non-coplanar plans and a seven-field coplanar plan were produced and optimised. In-house inverse-planning software (AutoBeam) was used to generate three-, five-, seven- and nine-field coplanar and non-coplanar plans and two volumetric intensity-modulated arc therapy (VMAT) plans. The resulting V(20), V(11), PTV(90), PTV(95) and mean lung dose were compared.Analysis of variance showed non-coplanar plans to have lower V(11) and higher PTV(90) and PTV(95) than coplanar plans. VMAT showed equivalent V(20) and target coverage when compared with the best non-coplanar plans, but with a faster delivery time (2min 8s versus 12min 40s).Inverse-planned five-field non-coplanar plans and VMAT improve target coverage while minimising the higher dose to normal lung tissue for SBRT of NSCLC compared with coplanar beam arrangements. VMAT is preferable because of significantly shorter treatment delivery times.

Introduction Patients with muscle invasive bladder cancer (MIBC) who are unfit and unsuitable for standard radical treatment with cystectomy or daily radiotherapy present a large unmet clinical need. Untreated, they suffer high cancer specific mortality and risk significant disease-related local symptoms. Hypofractionated radiotherapy (delivering higher doses in fewer fractions/visits) is a potential treatment solution but could be compromised by the mobile nature of the bladder, resulting in target misses in a significant proportion of fractions. Adaptive ‘plan of the day’ image-guided radiotherapy delivery may improve the precision and accuracy of treatment. We aim to demonstrate within a randomised multicentre phase II trial feasibility of plan of the day hypofractionated bladder radiotherapy delivery with acceptable rates of toxicity. Methods and analysis Patients with T2-T4aN0M0 MIBC receiving 36 Gy in 6-weekly fractions are randomised (1:1) between treatment delivered using a single-standard plan or adaptive radiotherapy using a library of three plans (small, medium and large). A cone beam CT taken prior to each treatment is used to visualise the anatomy and select the most appropriate plan depending on the bladder shape and size. A comprehensive radiotherapy quality assurance programme has been instituted to ensure standardisation of radiotherapy planning and delivery. The primary endpoint is to exclude &gt; 30% acute grade &gt; 3 non-genitourinary toxicity at 3 months for adaptive radiotherapy in patients who received &gt; 1 fraction (p0=0.7, p1=0.9, α=0.05, β=0.2). Secondary endpoints include local disease control, symptom control, late toxicity, overall survival, patient-reported outcomes and proportion of fractions benefiting from adaptive planning. Target recruitment is 62 patients. Ethics and dissemination The trial is approved by the London-Surrey Borders Research Ethics Committee (13/LO/1350). The results will be disseminated via peer-reviewed scientific journals, conference presentations and submission to regulatory authorities. Trial registration number NCT01810757 .

Purpose: To evaluate the impact of a customised immobilisation system on field placement accuracy, simulation and treatment delivery time, radiographer convenience and patient acceptability. Patients and methods: Thirty men receiving radical radiotherapy for prostate cancer were randomised using a cross over trial design to have radiotherapy planning and treatment given either in a conventional treatment position (CTP) or using an immobilisation system (IMS). The randomisation was to have either the CTP or IMS for the initial 3 weeks of radiotherapy after which patients were replanned and changed to the alternative treatment set-up. Treatment accuracy was measured using an electronic portal imaging device. Radiographers and patients completed weekly questionnaires. Results: Median simulation time was 22.5 min (range 20–30 min) in the CTP and 25 min (range 15–40 min) for the IMS (P<0.001). Median treatment time was 9 min for CTP (range 8–10 min), and 10 min (range 8.5–13.5 min) for IMS (P<0.001). Median isocentre displacement for anterior fields was 1.7 mm from the simulated isocentre for the CTP compared to 2.0 mm for IMS (P=0.07). For left lateral fields values were 1.8 and 1.8 mm (P=0.98), and for right lateral fields 2.1 and 1.7 mm (P=0.06), respectively. No clinically significant reduction in either systematic or random field placement errors was demonstrated. Radiographers reported that patients found the IMS more comfortable than CTP (P<0.001), but when using the IMS, they noticed greater difficulty in patient positioning (P<0.001), and alignment to skin tattoos (P<0.001). Conclusions: Although IMS may have been more comfortable, treatment accuracy was not improved compared to the CTP in our department. In addition, treatment took longer and patient set-up was more difficult.

This pilot study investigates whether an individualized fluid and fibre prescription combined with a constant treatment can improve rectal filling consistency during radiotherapy.Fibre, fluid intake and bowel function were assessed in 22 patients at a standard planning scan (SCT) and individualized dietary advice was prescribed to regularize bowel habit. Patients were requested to record frequency and type of bowel movements, fibre and fluid intake daily. Two subsequent CT scans were acquired at 7 (CCT1) and 10 days (CCT2) after SCT at a similar time. Rectal volume and gas were measured planning CT's and 'on treatment' cone beam CT scans. We hypothesised that the difference in volume between CCT1 and CCT2 would be less than the difference between SCT and CCT1.The mean (SD) change in volume between SCT to CCT1 and CCT1 to CCT2 was 5.68 cm(3) (26.2) and -8.6 cm(3) (40.1), respectively (p=0.292). Of the 22 patients scanned 20 provided a complete record of dietary intake and bowel motion. The majority of patients either achieved or exceeded prescription. Change in rectal gas was the only correlation with change in rectal volume.Patient self reporting of bowel motion, fibre, fluid intake was achievable but consistency of rectal filling was not improved. Improved understanding of the aetiology and management of rectal gas is indicated.

To effectively treat spine metastases, significant dose must be delivered to regions surrounding the spinal cord. We present a study comparing both step-and-shoot intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques to deliver a concomitant hypofractionated prescription dose to the diseased region and to the involved vertebrae.Seven-field IMRT and a single arc VMAT were inversely planned on five (two cervical and three thoracic) spinal metastatic patients. Planning target volumes PTVm (macroscopic) and PTVe (elective involved vertebrae) and associated organs at risk were localised. Mean doses of 35 Gy to PTVm and 20 Gy to PTVe were prescribed in five fractions. Dose statistics, estimated delivery time and results of verification using Delta(4) (ScandiDos, Uppsala, Sweden) were compared.Deliverable plans were achieved with both IMRT and VMAT. The coverage to PTV was similar for both IMRT and VMAT (p=0.5) and the dose to the regions adjacent to the spinal cord was 1% higher with VMAT (p=0.04). The mean delivery time for VMAT was 3.5 min compared with 10.5 min for IMRT. Fewer monitor units were required to deliver IMRT than to deliver VMAT. The median (range) percentage of measured points with a γ-index <1 with 3%/3 mm was 100 (99.9-100)% for IMRT and 100 (88.5-100)% for VMAT.Both VMAT and IMRT can deliver the concomitant hypofractionated regime proposed, and both offer different benefits in dose delivery. IMRT is currently preferred for its superior pre-treatment verification results and shorter planning times.This study explores the feasibility of delivering tumouricidal doses of radiation to metastatic spine disease in the vicinity of the spinal cord.

AimsAdaptive radiotherapy (ART) is an emerging advanced treatment option for bladder cancer patients. Therapeutic radiographers (RTTs) are central to the successful delivery of this treatment. The purpose of this work was to evaluate the image-guided radiotherapy (IGRT) and ART experience of RTTs before participating in the RAIDER trial. A plan of the day (PoD) quality assurance programme was then implemented. Finally, the post-trial experience of RTTs was evaluated, together with the impact of trial quality assurance participation on their routine practice.Materials and methodsA pre-trial questionnaire to assess the experience of the RTT staff group in IGRT and ART in bladder cancer was sent to each centre. Responses were grouped according to experience. The PoD quality assurance programme was implemented, and the RAIDER trial commenced. During stage 1 of the trial, RTTs reported difficulties in delivering PoD and the quality assurance programme was updated accordingly. A follow-up questionnaire was sent assessing experience in IGRT and ART post-trial. Any changes in routine practice were also recorded.ResultsThe experience of RTTs in IGRT and ART pre-trial varied. For centres deemed to have RTTs with more experience, the initial PoD quality assurance programme was streamlined. For RTTs without ART experience, the full quality assurance programme was implemented, of which 508 RTTs completed. The quality assurance programme was updated (as the trial recruited) and it was mandated that at least one representative RTT (regardless of pre-trial experience) participated in the update in real-time. The purpose of the updated quality assurance programme was to provide further support to RTTs in delivering a complex treatment. Engagement with the updated quality assurance programme was high, with RTTs in 24/33 centres participating in the real-time online workshop. All 33 UK centres reported all RTTs reviewed the updated training offline. Post-trial, the RTTs' experience in IGRT and ART was increased.ConclusionOverall, 508 RTTs undertook the PoD quality assurance programme. There was a high engagement of RTTs in the PoD quality assurance programme and trial. RTTs increased their experience in IGRT and ART and subsequently updated their practice for bladder cancer and other treatment sites.

AimsAdding concurrent (chemo)therapy to radiotherapy improves outcomes for muscle-invasive bladder cancer patients. A recent meta-analysis showed superior invasive locoregional disease control for a hypofractionated 55 Gy in 20 fractions schedule compared with 64 Gy in 32 fractions. In the RAIDER clinical trial, patients undergoing 20 or 32 fractions of radical radiotherapy were randomised (1:1:2) to standard radiotherapy or to standard-dose or escalated-dose adaptive radiotherapy. Neoadjuvant chemotherapy and concomitant therapy were permitted. We report exploratory analyses of acute toxicity by concomitant therapy-fractionation schedule combination.Materials and methodsParticipants had unifocal bladder urothelial carcinoma staged T2-T4a N0 M0. Acute toxicity was assessed (Common Terminology Criteria for Adverse Events) weekly during radiotherapy and at 10 weeks after the start of treatment. Within each fractionation cohort, non-randomised comparisons of the proportion of patients reporting treatment emergent grade 2 or worse genitourinary, gastrointestinal or other adverse events at any point in the acute period were carried out using Fisher's exact tests.ResultsBetween September 2015 and April 2020, 345 (163 receiving 20 fractions; 182 receiving 32 fractions) patients were recruited from 46 centres. The median age was 73 years; 49% received neoadjuvant chemotherapy; 71% received concomitant therapy, with 5-fluorouracil/mitomycin C most commonly used: 44/114 (39%) receiving 20 fractions; 94/130 (72%) receiving 32 fractions. The acute grade 2+ gastrointestinal toxicity rate was higher in those receiving concomitant therapy compared with radiotherapy alone in the 20-fraction cohort [54/111 (49%) versus 7/49 (14%), P < 0.001] but not in the 32-fraction cohort (P = 0.355). Grade 2+ gastrointestinal toxicity was highest for gemcitabine, with evidence of significant differences across therapies in the 32-fraction cohort (P = 0.006), with a similar pattern but no significant differences in the 20-fraction cohort (P = 0.099). There was no evidence of differences in grade 2+ genitourinary toxicity between concomitant therapies in either the 20- or 32-fraction cohorts.ConclusionGrade 2+ acute adverse events are common. The toxicity profile varied by type of concomitant therapy; the gastrointestinal toxicity rate seemed to be higher in patients receiving gemcitabine.

<h2>Abstract</h2><h3>Objectives</h3> The aim of this review was to search existing literature to identify comfort interventions that can be used to assist an adult patient to undergo complex radiotherapy requiring positional stability for periods greater than 10 min. The objectives of this review were to; 1) identify comfort interventions used for clinical procedures that involve sustained inactivity similar to radiotherapy; 2) define characteristics of comfort interventions for future practice; and 3) determine the effectiveness of identified comfort interventions. The Preferred Reporting Items for Systematic Reviews and meta-analyses statement and the Template-for-Intervention-Description-and Replication guide were used. <h3>Key findings</h3> The literature search was performed using PICO criteria with five databases (AMED, CINAHL EMBASE, MEDLINE, PsycINFO) identifying 5269 titles. After screening, 46 randomised controlled trials met the inclusion criteria. Thirteen interventions were reported and were grouped into four categories: Audio–visual, Psychological, Physical, and Other interventions (education/information and aromatherapy). The majority of aromatherapy, one audio–visual and one educational intervention were judged to be clinically significant for improving patient comfort based on anxiety outcome measures (effect size ≥ 0.4, mean change is greater than the Minimal-Important-Difference and low-risk-of-bias). Medium to large effect sizes were reported in many interventions where differences did not exceed the Minimal-Important-Difference for the measure. These interventions were deemed worthy of further investigation. <h3>Conclusion</h3> Several interventions were identified that may improve comfort during radiotherapy assisting patients to sustain and endure the same position over time. This is crucial for the continual growth of complex radiotherapy requiring a need for comfort to ensure stability for targeted treatment. <h3>Implications for practice</h3> Further investigation of comfort interventions is warranted, including tailoring interventions to patient choice and determining if multiple interventions can be used concurrently to improve effectiveness.

Introduction Daily radiotherapy delivered with radiosensitisation offers patients with muscle invasive bladder cancer (MIBC) comparable outcomes to cystectomy with functional organ preservation. Most recurrences following radiotherapy occur within the bladder. Increasing the delivered radiotherapy dose to the tumour may further improve local control. Developments in image-guided radiotherapy have allowed bladder tumour-focused ‘plan of the day’ radiotherapy delivery. We aim to test within a randomised multicentre phase II trial whether this technique will enable dose escalation with acceptable rates of toxicity. Methods and analysis Patients with T2-T4aN0M0 unifocal MIBC will be randomised (1:1:2) between standard/control whole bladder single plan radiotherapy, standard dose adaptive tumour-focused radiotherapy or dose-escalated adaptive tumour-focused radiotherapy (DART). Adaptive tumour-focused radiotherapy will use a library of three plans (small, medium and large) for treatment. A cone beam CT taken prior to each treatment will be used to visualise the anatomy and inform selection of the most appropriate plan for treatment. Two radiotherapy fractionation schedules (32f and 20f) are permitted. A minimum of 120 participants will be randomised in each fractionation cohort (to ensure 57 evaluable DART patients per cohort). A comprehensive radiotherapy quality assurance programme including pretrial and on-trial components is instituted to ensure standardisation of radiotherapy planning and delivery. The trial has a two-stage non-comparative design. The primary end point of stage I is the proportion of patients meeting predefined normal tissue constraints in the DART group. The primary end point of stage II is late Common Terminology Criteria for Adverse Events grade 3 or worse toxicity aiming to exclude a rate of &gt;20% (80% power and 5% alpha, one sided) in each DART fractionation cohort. Secondary end points include locoregional MIBC control, progression-free survival overall survival and patient-reported outcomes. Ethics and dissemination This clinical trial is approved by the London-Surrey Borders Research Ethics Committee (15/LO/0539). The results when available will be disseminated via peer-reviewed scientific journals, conference presentations and submission to regulatory authorities. Trial registration number NCT02447549

This paper presents the results of a survey of the routine use of permanent marks for radiotherapy in the UK. This was undertaken to provide an overview of current practice. Permanent marks are a somewhat invasive procedure, and should be subject to scrutiny and judicious application.The authors reviewed the literature on international radiotherapy permanent marking practice. Common themes that emerged were the psychology of permanent marking and ink-type considerations, current practice and training, and safety. These were used to develop a questionnaire in order to form an overview of the use of marks nationally, and to identify any recurrent issues. The questionnaire also sought information regarding locations and numbers of permanent marks used for common treatment sites. The survey was sent to 71 departments in the UK using email.70% of departments responded. 62% of departments reported patients who had refused permanent marks. The reasons for refusal varied. India or drawing ink was used in 49 of the 51 departments (96%). The most common teaching method of tattooing involved combined observation and verbal coaching. Most departments had a written procedure for tattooing, but some did not. Although sharps injuries were rare, they were documented.Most departments in the UK had encountered patient refusal of permanent marks, with breast patients representing the largest group which declined. There is variation in practice throughout the UK, and the equipment used is not specialised for tattooing purposes. Sharps injuries, although rare, do occur, and training methods are not consistent.The requirement for national guidelines is posited. Further investigation into the need for permanent marks in an era of state-of-the-art imaging technology is also required.

IntroductionWith the implementation of new radiotherapy technology, it is imperative that patient experience is investigated alongside efficacy and outcomes. This paper presents the development of a specifically designed validated questionnaire and a first report of international multi-institutional preliminary patient experience of MRI-guided adaptive radiotherapy (MRgART) on the 1.5 T MR-Linac (MRL).MethodsA patient experience questionnaire was developed and validated before being distributed to the Elekta MRL Consortium, to gather first patient-reported experience from participating centres worldwide. The final version of the questionnaire contains 18 questions covering a range of themes and was scored on a Likert scale of 0–3. Responses were post-processed so that a score of 0 represents a negative response and 3 represents the most favourable response. These results were analysed for patient-reported experience of treatment on the MRL. Results were also analysed for internal consistency of the questionnaire using Chronbach’s Alpha and the questionnaire contents were validated for relevance using content validity indexes (CVI).Results170 responses were received from five centres, representing patients with a wide range of tumour treatment sites from four different countries. MRgART was well tolerated with an 84% favourable response across all questions and respondents. When analysed by theme, all reported the highest percentage of results in the favourable categories (2 and 3). Internal consistency in the questionnaire was high (Cronbach’s α = 0.8) and the item-level CVI for each question was 0.78 or above and the Scale-level CVI was 0.93, representing relevant content.ConclusionThe developed questionnaire has been validated as relevant and appropriate for use in reporting experience of patients undergoing treatment on the MRL. The overall patient-reported experience and satisfaction from multiple centres within the Elekta MRL Consortium was consistently high. These results can reinforce user confidence in continuing to expand and develop MRL use in adaptive radiotherapy.

To investigate the feasibility of fully automated detection of fiducial markers implanted into the prostate using portal images acquired with an electronic portal imaging device.We have made a direct comparison of 4 different methods (2 template matching-based methods, a method incorporating attenuation and constellation analyses and a cross correlation method) that have been published in the literature for the automatic detection of fiducial markers. The cross-correlation technique requires a-priory information from the portal images, therefore the technique is not fully automated for the first treatment fraction. Images of 7 patients implanted with gold fiducial markers (8 mm in length and 1 mm in diameter) were acquired before treatment (set-up images) and during treatment (movie images) using 1MU and 15MU per image respectively. Images included: 75 anterior (AP) and 69 lateral (LAT) set-up images and 51 AP and 83 LAT movie images. Using the different methods described in the literature, marker positions were automatically identified.The method based upon cross correlation techniques gave the highest percentage detection success rate of 99% (AP) and 83% (LAT) set-up (1MU) images. The methods gave detection success rates of less than 91% (AP) and 42% (LAT) set-up images. The amount of a-priory information used and how it affects the way the techniques are implemented, is discussed.Fully automated marker detection in set-up images for the first treatment fraction is unachievable using these methods and that using cross-correlation is the best technique for automatic detection on subsequent radiotherapy treatment fractions.

Aims To quantify the inter-fractional variation in bladder volume and position during a course of bladder radiotherapy, and to assess the feasibility of reducing the planning target volume (PTV) internal margin using an empty bladder protocol. Materials and methods Weekly computed tomography scans were taken immediately after micturition on 15 patients undergoing radical radiotherapy for bladder cancer. Bladder volume and positional variation were compared by co-registration of the serial computed tomography scans with the initial planning scan and a single ‘full’ scan at the onset of treatment for each patient. A PTV was generated on the initial planning scan using both our departmental standard of 1.5 cm and a reduced 1 cm isotropic internal margin around the target (whole bladder) and the relative proportion of the bladder breaching the PTV using both margins compared. Results The mean post void residual volume from the planning scan was 112 cm3 (standard deviation 42 cm3). The mean weekly variation in bladder volume relative to the planning volume was 0–12% (standard deviation 20–34%) with no observable trends over time. No statistically significant differences were seen in the proportion of bladder breaching the 1.5 and 1 cm internal margin (P=0.18). Regression analysis showed that it is possible to ensure complete coverage of the bladder with a 1 cm margin, providing the volume did not exceed over 50% of the initial planning scan volume. Conclusion Using an empty bladder protocol and where on-line imaging is available it is feasible to reduce the internal margin of the PTV from 1.5 to 1cm, providing the volumes do not exceed >50% of the planning scan volume.

Research from Allied Health Professionals (AHPs) is anecdotally known to lag behind that of other professions.The developing research landscape within other therapies and internationally led us to question how UK practice in therapeutic radiography was developing.The aim of the survey was to audit research capacity across therapy radiography in the UK. MethodAn electronic survey was sent to Radiotherapy Service Managers (RSM) and research leads in each of the radiotherapy centres in the UK.An adapted version of the 'Auditing Research Capacity' tool (ARC © tool) was used as the basis of the questionnaire. ResultsA total of 45 RSM responded to the survey (67% response rate) and 30 Research radiographers (RR)(45% response rate).A total of 51 RR were in post equating to 40.3 whole time equivalents and averaging 1 RR per centre.Variation was evident in the commitment to the development of a research culture identified by practices such as linking research to the business planning cycle, inclusion of research in recruitment and advertising materials, or having a nominated therapeutic radiographer lead on research for the department.Over a third of responding centres did not have a research strategy and training for RRs was limited; specifically in areas such as writing funding bids, writing for publication and the research and governance process. ConclusionA number of short and long-term strategies are proposed that should enhance a positive research culture and improve research capacity for therapeutic radiography led research.These include utilisation of the existing infrastructure provided by the National Institute for Health Research, a lead or co-ordinator for research activity with a remit to motivate others.Development of links and networks, and the development of a research strategy linked to wider Trust research priorities.The research strategy should include mentoring or developing appropriate research skills for those engaged in research (including higher degree qualifications).RSMs should also encourage peerreviewed publications, and conference presentations from all staff to ensure research results are disseminated to the wider profession.

Background and purposeHypofractionated bladder RT with or without image guided adaptive planning (HYBRID) is a multicentre clinical trial investigating “Plan of the Day” (PoD) adaptive radiotherapy for bladder cancer. To ensure correct PoD selection a pre-accrual guidance and assessment module was developed as part of an image guided radiotherapy quality assurance (IGRT QA) credentialing programme. This study aimed to evaluate its feasibility and effectiveness across multiple recruiting centres.Materials and methodsIndividuals from participating centres remotely accessed an image database in order to complete the PoD module. An assessment score of ≥83% was required in order to receive QA approval. A questionnaire was used to gather user feedback on the module. PoD decisions for the first patient at each recruiting centre were retrospectively reviewed for protocol adherence.Results71 radiation therapists (RTTs) from 10 centres completed the PoD module. The median assessment score was 92% (Range: 58–100%) with 79% of RTTs passing the assessment on first attempt. All questionnaire respondents reported that the PoD module prepared them for plan selection. In 51/60 of on-trial treatments reviewed, the PoD selected by the centre agreed with QA reviewers.ConclusionsThe PoD QA module was successfully implemented in a multicentre trial and enabled pre-accrual assessment of protocol understanding. This increased operator confidence and resulted in appropriate PoD selection on-trial.

<h2>Abstract</h2><h3>Aims</h3> Node-positive bladder cancer (NPBC) carries a poor prognosis and has traditionally been treated palliatively. However, surgical series suggest that a subset of NPBC patients can achieve long-term control after cystectomy and lymph node dissection. There is little published data regarding the use of radiotherapy to treat NPBC patients. This is in part due to concerns regarding the toxicity of whole-pelvis radiotherapy using conventional techniques. We hypothesised that, using intensity-modulated radiotherapy (IMRT), the pelvic nodes and bladder could be treated within a radical treatment volume with acceptable toxicity profiles. <h3>Materials and methods</h3> The Intensity-modulated Pelvic Node and Bladder Radiotherapy (IMPART) trial was a phase II single-centre prospective study designed to assess the feasibility of delivering IMRT to treat the bladder and pelvic nodes in patients with node-positive or high-risk node-negative bladder cancer (NNBC). The primary end point was meeting predetermined dose constraints. Secondary end points included acute and late toxicity, pelvic relapse-free survival and overall survival. <h3>Results</h3> In total, 38 patients were recruited and treated between June 2009 and November 2012; 22/38 (58%) had NPBC; 31/38 (81.6%) received neoadjuvant chemotherapy; 18/38 (47%) received concurrent chemotherapy; 37/38 (97%) patients had radiotherapy planned as per protocol. Grade 3 gastrointestinal and genitourinary acute toxicity rates were 5.4 and 20.6%, respectively. At 1 year, the grade 3 late toxicity rate was 5%; 1-, 2- and 5-year pelvic relapse-free survival rates were 55, 37 and 26%, respectively. The median overall survival was 1.9 years (95% confidence interval 1.1–3.8) with 1-, 2- and 5-year overall survival rates of 68, 50 and 34%, respectively. <h3>Conclusion</h3> Delivering IMRT to the bladder and pelvic nodes in NPBC and high-risk NNBC is feasible, with low toxicity and low pelvic nodal recurrence rates. Long-term control seems to be achievable in a subset of patients. However, relapse patterns suggest that strategies targeting both local recurrence and the development of distant metastases are required to improve patient outcomes.

To systematically identify the preferred magnetic resonance imaging (MRI) sequences following volunteer imaging on a 1.5 Tesla (T) MR-Linear Accelerator (MR Linac) for future protocol development.Non-patient volunteers were recruited to a Research and Ethics committee approved prospective MR-only imaging study on a 1.5T MR Linac system. Volunteers attended 1-3 imaging sessions that included a combination of mDixon, T1w, T2w sequences using 2-dimensional (2D) and 3-dimensional (3D) acquisitions. Each sequence was acquired over 2-7 minutes and reviewed by a panel of 3 observers to evaluate image quality using a visual grading analysis based on a 4-point Likert scale. Sequences were acquired and modified iteratively until deemed fit for purpose (online image matching or re-planning) and all observers agreed they were suitable in 3 volunteers.26 volunteers underwent 31 imaging sessions of six general anatomical regions. Images were acquired in one or two of six general anatomical regions: male pelvis (n = 9), female pelvis (n = 4), chestwall/breast (n = 5), lung/oesophagus (n = 5), abdomen (n = 3) and head and neck (n = 5). Images were acquired using a pre-defined exam-card that on average, included six sequences (range 2-10), with a maximum scan time of approximately one hour. The majority of observers preferred T2-weighted sequences. The thorax teams were the only groups to prefer T1-weighted imaging.An iterative process identified sequence agreement in all anatomical regions. These sequences will now be evaluated in patient volunteers.This manuscript is the first publication sharing the results of the first systematic selection of MRI sequences for use in on-board MRI-guided radiotherapy by end-users (therapeutic radiographers and clinical oncologists) in healthy volunteers.

The uptake of new technologies has varied internationally and there have often been barriers to implementation. On-line adaptive radiotherapy (ART) promises to improve patient outcome. This survey focuses on the implementation phase of delivering ART and professional roles and responsibilities currently involved in the workflow and changes which may be expected in the future.A 38 question survey included aspects on current practice; professional responsibilities; benefits and barriers; and decision making and responsibilities. For the purposes of the questionnaire and paper, ART was considered where tumour and /or organs at risk were contoured and re-planning was performed on-line. The questionnaire was electronically distributed via radiotherapy networks.Nineteen international responses were received. Europe (n = 11), United States of America (n = 4); Canada (n = 2), Australia (n = 1) and Hong Kong (n = 1). The majority of centres started using ART in either 2018 (n = 7) or 2019 (n = 6). Four centres started treating with ART between 2015 and 2017, and the first was in 2014. Centres initially treated prostate and oligometastases patients, expanding to treat prostate, oligometastases, pancreas and rectum. The majority of centres were working in conventional roles, however moving towards radiographers taking more responsibility in contouring organs at risk (OAR), target and dosimetry. The three most important criteria chosen by medical doctors to determine if ART should be used were overall gross anatomy changes of target and OAR, target not covered by planning target volume (PTV) and OAR close to the high dose area. There was no clear consensus on the minimum improvement in dose to target or reduction in dose to OAR to warrant adaption.On-line ART has been implemented successfully internationally. Initial practice maintains conventional professional roles and responsibilities, however there is trend to changing roles for the future. There is little consensus regarding the triggers of adaption.

Interfraction motion during cervical cancer radiotherapy is substantial in some patients, minimal in others. Non-adaptive plans may miss the target and/or unnecessarily irradiate normal tissue. Adaptive radiotherapy leads to superior dose-volume metrics but is resource-intensive. The aim of this study was to predict target motion, enabling patient selection and efficient resource allocation.Forty cervical cancer patients had CT with full-bladder (CT-FB) and empty-bladder (CT-EB) at planning, and daily cone-beam CTs (CBCTs). The low-risk clinical target volume (CTVLR) was contoured. Mean coverage of the daily CTVLR by the CT-FB CTVLR was calculated for each patient. Eighty-three investigated variables included measures of organ geometry, patient, tumour and treatment characteristics. Models were trained on 29 patients (171 fractions). The Two-CT multivariate model could use all available data. The Single-CT multivariate model excluded data from the CT-EB. A univariate model was trained using the distance moved by the uterine fundus tip between CTs, the only method of patient selection found in published cervix plan-of-the-day studies. Models were tested on 11 patients (68 fractions). Accuracy in predicting mean coverage was reported as mean absolute error (MAE), mean squared error (MSE) and R2.The Two-CT model was based upon rectal volume, dice similarity coefficient between CT-FB and CT-EB CTVLR, and uterine thickness. The Single-CT model was based upon rectal volume, uterine thickness and tumour size. Both performed better than the univariate model in predicting mean coverage (MAE 7 %, 7 % and 8 %; MSE 82 %2, 65 %2, 110 %2; R2 0.2, 0.4, -0.1).Uterocervix motion is complex and multifactorial. We present two multivariate models which predicted motion with reasonable accuracy using pre-treatment information, and outperformed the only published method.

Swallow-related motion of the larynx is most significant in the cranio-caudal directions and of` short duration. Conventional target definition for radical radiation therapy includes coverage of the whole larynx. This study longitudinally examined respiration- and swallow-related laryngeal motions using cine-magnetic resonance imaging. We further analyzed the dosimetry to organs at risk by comparing 3D-conformal radiation therapy (3D-CRT), volumetric modulated arc therapy (VMAT), and intensity modulated radiation therapy (IMRT) techniques.Fifteen patients with T1-2 N0 glottic squamous cell carcinomas were prospectively recruited for up to 3 cine-MRI scans on the Elekta Unity MR-Linear accelerator, at the beginning, middle, and end of a course of radical radiation therapy. Swallow frequency and motion of the hyoid bone, cricoid and thyroid cartilages, and vocal cords were recorded during swallow and rest. Adapted treatment volumes consisted of gross tumor volume + 0.5-1 cm to a clinical target volume with an additional internal target volume (ITV) for personalized resting-motion. Swallow-related motion was deemed infrequent and was not accounted for in the ITV. We compared radiation therapy plans for 3D-CRT (whole larynx), VMAT (whole larynx), and VMAT and IMRT (ITV for resting motion).Resting- and swallow-related motions were most prominent in the cranio-caudal plane. There were no significant changes in the magnitude of motion over the course of radiation therapy. There was a trend of a progressive reduction in the frequency of swallow. Treatment of partial larynx volumes with intensity modulated methods significantly reduced the dose to carotid arteries, compared with treatment of whole larynx volumes. Robustness analysis demonstrated that when accounting for intrafraction swallow, the total dose delivered to the ITV/planning target volume was maintained at above 95%.Swallow-related motions are infrequent and accounting for resting motion in an ITV is sufficient. VMAT/IMRT techniques that treat more conformal targets can significantly spare critical organs at risk such as the carotid arteries and thyroid gland, potentially reducing the risk of carotid artery stenosis-related complications and other long-term complications.

The radiation therapy (RT) landscape is continuously evolving, necessitating adaptation in roles and responsibilities of radiation therapists (RTTs). Advanced Practice Radiation Therapists (APRTs) have taken on a proactive role in expanding services and assuming responsibilities within multi-professional teams. A European Society for Radiotherapy and Oncology (ESTRO) brought geographically diverse and experienced RTTs together, to discuss how advanced practice (AP) in the RTT profession should be future-proofed and create a global platform for collaboration. Challenges in achieving consensus and standardisation of APRT was identified across jurisdictions, emphasising the importance of international collaboration. Whilst highlighting the pivotal role of APRTs in driving innovation, improving patient care, and navigating the complexities of modern RT practice, this position paper presents outcomes and recommendations from the workshop. Discussions highlighted the need for standardised role definitions, education frameworks, regulatory support, and career development pathways to enable the advancement of APRT effectively. Increasing networks and collaboration is recommended to ensure APRTs can shape the future of RT.

Strict safety practices are essential to ensure the safety of patients and staff in Magnetic Resonance Imaging (MRI). Training regarding the fundamentals of MRI safety is well-established and commonly agreed upon. However, more complex aspect of screening patients, such as image review or screening of unconscious patients/patients with communication difficulties is less well discussed. The current UK and USA guidelines do not suggest the use of communication training for MRI staff nor indicate any training to encourage reviewing images in the screening process. This review aims to map the current guidance regarding safety and patient screening training for MRI diagnostic and therapeutic radiographers.A systematic search of PubMed, Trip Medical database and Radiography journal was conducted. Studies were chosen based on the review objectives and pre-determined inclusion/exclusion criteria using the PRISMA-ScR framework.Twenty-four studies were included in the review, which identified some key concepts including MRI safety training and delivery methods, screening and communication, screening of unconscious or non-ambulatory patients and the use of imaging.Training gaps lie within the more complex elements of screening such as the inclusiveness of question phrasing, particularly to the neurodivergent population, how we teach radiographers to screen unconscious/unresponsive patients and using imaging to detect implants.The consequences of incomplete or inaccurate pre-MRI safety screening could be the introduction of unexpected implants into the scanner or forgoing MRI for a less desirable modality. The development of enhanced training programs in implant recognition using imaging and communication could complement existing training.

<h2>Abstract</h2><h3>Introduction</h3> Adapting radiotherapy services with workforce innovation using skills-mix or task-shifting optimises resources, supporting current and future demands. Advanced practitioners (APs) work at a different level of practice (beyond initial registration) across four pillars: clinical practice, leadership and management, education, and research. There is limited cross-country research on the advanced therapeutic radiographers/radiation therapists (TR/RTTs), particularly in Europe. This study aimed to investigate European radiotherapy stakeholders' perceptions regarding current and future advanced practice (AP). <h3>Methods</h3> From June to September 2022, one-to-one online semi-structured interviews were conducted in English, and audio and video were recorded. Full verbatim audio files were independently transcribed and checked by interviewer and interviewees. Braun and Clarke's seven steps guided the thematic analysis (using NVivo). <h3>Results</h3> Thirty-three interviewees working or studying in 16 European countries represented practitioners (n=14), managers (n=6), educators (n=4), professional bodies (n=4), students (n=3), and regulators (n=2). Four overarching themes emerged: "AP drivers and outcomes", "AP challenges <i>vs</i> enablers", "Current <i>vs</i> future AP", "Becoming and being advanced practitioner". Participants identified research as the neglected AP pillar due to a lack of protected time, limited staff skills, no research culture, no funding, workload, and clinical priorities. Interviewees highlighted the importance of consistency in job titles, harmonisation of education models and curricula, definition of AP requirements, and support for all AP pillars through job plans and workforce planning. <h3>Conclusion</h3> Neither the profession nor education of TR/RTTs are harmonised across Europe, which is highly reflected in advanced-level practice. Advanced TR/RTTs should work across all pillars, including research, and these should be embedded in master's programmes, including leadership. <h3>Implications for practice</h3> This study highlights a policy gap in the education and practice of APs in radiotherapy.

OBJECTIVE Stereotactic conformal radiotherapy (SCRT) is a high precision technique of fractionated radiotherapy which ensures accurate delivery of radiation with reduction in the volume of normal tissue irradiated as compared to conventional external beam radiotherapy. We describe the technique and preliminary experience of SCRT in patients with residual and recurrent pituitary adenomas. PATIENTS AND METHODS Between February 1995 and March 1999, 22 patients (mean age: 45.3, range: 20–67 years) with residual or recurrent pituitary adenomas (13 nonfunctioning, nine secretory) were treated with SCRT. All were immobilized in a relocatable Gill–Thomas–Cosman (GTC) frame and tumour was localized on a postcontrast planning computerized tomography (CT) and MRI scan. The gross tumour volume (GTV) and the critical structures were outlined on contiguous 2–3 mm separated slices. A margin of 5 mm (12 patients) to 10 mm (10 patients) was grown around GTV in three‐dimensions (3‐D) to generate the planning target volume (PTV). The treatment was delivered by three (five patients) and four (17 patients) maximally separated conformal fixed fields with each field conformed to the shape of the tumour using customized lead alloy blocks (19 patients) or multileaf collimator (three patients). The patients were treated on a 6‐MV linear accelerator to a dose of 45 Gy in 25 fractions (18 patients) and 50 Gy in 30 fractions (four patients). RESULTS The technique of SCRT has become a part of the routine work of the radiotherapy department. The treatment was well tolerated with minimal acute toxicity. One patient developed transient quadrantanopia 2 weeks after treatment with full recovery after a short course of corticosteroids. One patient had a transient visual deterioration 7 months after treatment due to cystic degeneration of the tumour which fully recovered following surgical decompression. Nine of the 15 patients presenting with visual impairment had improvement after treatment and the visual status remained stable in all others. One patient with acromegaly and one with a prolactinoma achieved normalization of elevated hormonal abnormality four and 10 months after SCRT, respectively. The remaining seven patients with a secretory adenoma had declining hormone levels at last follow‐up. Newly initiated hormone replacement therapy was required in five patients. At a median follow‐up of 9 months (range 1–44 months), the 1 and 2 year actuarial progression free and overall survival were 100%. CONCLUSION Stereotactic conformal radiotherapy is a high precision technique suitable for the treatment of pituitary adenomas requiring radiotherapy. Preliminary results suggest effective tumour control and low toxicity within the range expected for conventional external beam radiotherapy. While the technique is of potential benefit in reducing the volume of normal brain irradiated, the advantages in terms of sustained tumour control and reduced toxicity over conventional radiotherapy need to be demonstrated in long‐term prospective studies.

In this study, we aimed to create a comprehensive register of UK research radiographers (RRs), identify perceived training needs and make recommendations for the forward planning of the RR community in 2007 and 2008. Radiotherapy departments in England were sent an Academic Clinical Oncology and Radiobiology Research Network (ACORRN) questionnaire on RR establishment, demographics, role descriptions, research responsibilities, funding, time allocations, research skills and barriers to research. ACORRN received 85 replies from 51 departments of which just 5 RRs had a 100% research role. 70 radiographers participated in research at some level. 13 departments did not have any RRs. The RR role was defined as both developmental and specialist in nature by 43% of respondents; the remainder had a more diverse role. The National Health Service Trusts were responsible for funding 40% of RRs; the rest were fully or part-funded by national or local cancer networks, charity appeals and industry. 61% of RRs did not have dedicated academic time despite 93% being required to teach or support others. Critical barriers reported in conducting research were time, funding and supporting others In conclusion, the ACORRN RR Working Party makes the following recommendations for the future development of the community: the role of research should be viewed as an integral feature, at least one RR should be employed per radiotherapy department, the RR community must work together, dedicated research time is required, along with stable funding, RRs require more training, RRs need more support to accomplish the diversity of roles.

Purpose. Oesophageal cancers are difficult to visualise on volumetric imaging and reliable surrogate are needed for accurate tumour registration. The aim of this investigation is to evaluate the effect of a user defined volume with automated registration techniques using commercially available software with the on-board volumetric imaging for treatment verification of oesophageal cancer and determine the optimum location of this volume. Material and methods. In 20 patients four ‘clipbox’(C) volumes were defined: C-planning target volume (PTV), C-carina, C-vertebrae, C-thorax. The set-up corrections (translational and rotational) for C-PTV were compared to the corrections using C-carina, C-vertebrae and C-thorax. Results. Six hundred and eight registrations were performed. The best concordance in set-up corrections was found in the superior/inferior direction between C-PTV and C-carina (76%). In the right/left and anterior/posterior direction, better agreement was found between C-PTV and C-thorax with 80% and 76% agreement, respectively. Automatic ‘bone’ registration using C-vertebrae failed in 28% of scans. The correlation ratio between C-PTV and C-carina (n = 4) for mid-oesophageal tumours was 0.88, 0.79, and 0.95 in the right/left, superior/inferior and anterior/posterior directions, respectively. Conclusion. The defined volume for matching is important for oesophageal tumours. The alignment ‘clipbox’ and registration method selected can affect the displacements obtained. This may best be determined by tumour location and highlights the need to diversify protocols within one tumour treatment site. Further analysis is required to validate carina as a tumour surrogate for mid-oesophageal tumours.

Prospectively compare patient setup accuracy and intrafraction motion of a standard 3-point thermoplastic mask with the Gill-Thomas-Cosman relocatable stereotactic frame, during fractionated cranial radiation therapy using the ExacTrac system (Brainlab AG Feldkirchen, Germany) for daily online correction.The number of fractions with all postcorrection and post-treatment errors <2 mm was assessed in 21 patients undergoing fractionated stereotactic radiation therapy (13 frame setup, 8 mask setup) using daily online correction. Achievable patient setup accuracy and total intrafraction motion were evaluated. The relative contributions of movement during floor rotation and patient movement to intrafraction motion were calculated.With daily online correction, patient setup margins can be reduced from 1, 5, and 4 mm in the lateral, longitudinal, and vertical axes for mask setup and from 1-2, 2, and 1 mm, respectively, for frame setup to <1 mm isotropically for either immobilization system. Intrafraction movement was small for frame setup (mean [SD], -0.3 [0.3], -1.1[0.4], and -0.2 [0.6] in lateral, longitudinal and vertical axes, respectively; maximum, -2.7 mm [longitudinal axis]), and mask-setup (mean [SD], -0.4 [0.5], -0.8 [0.7], and 0.0 [0.3], respectively; maximum, -2.0 mm [longitudinal axis]) and is mainly due to floor rotation. Postcorrection and post-treatment errors were all <2 mm in 95% and 99% of fractions in the mask and frame, respectively, meeting the criteria for a 3-mm clinical target volume-planning target volume margin for either immobilization method.Daily online correction can compensate for less precise immobilization and permits stereotactic margins to be used for standard thermoplastic masks without the need for specialized mask systems.

IGRT in cervical cancer treatment delivery is complex due to significant target and organs at risk (OAR) motion. Implementing image assessment of soft-tissue target and OAR position to improve accuracy is recommended. We report the development and refinement of a training and competency programme (TCP), leading to on-line Radiation Therapist (RTT) led soft-tissue assessment, evaluated by a prospective audit.The TCP comprised didactic lectures and practical sessions, supported by a comprehensive workbook. The content was decided by a team comprised of Clinical Oncologists, RTTs, and Physicists. On completion of training, RTT soft-tissue review proficiency (after bony anatomy registration) was assessed against a clinician gold-standard from a database of 20 cervical cancer CBCT images. Reviews were graded pass or fail based on PTV coverage assessment and decision taken in concordance with the gold-standard. Parity was set at ≥80% agreement.The initial TCP (stage one) focussed on offline verification and decision making. Sixteen RTTs completed this stage, four achieved ≥80%. This was not sufficient to support clinical implementation.The TCP was redesigned, more stringent review guidelines and greater anatomy teaching was added. TCP stage two focussed on online verification and decision making supported by a decision flowchart. Twenty-one RTTs completed this TCP, all achieved ≥80%. This supported clinical implementation of RTT-led soft-tissue review under prospective audit conditions.The prospective audit was conducted between March 2017 and August 2017. Daily online review was performed by two trained RTTs. Online review and decision making proficiency was evaluated by a clinician.Thirteen patients were included in the audit. Daily online RTT-led IGRT was achieved for all 343 fractions. Two-hundred CBCT images were reviewed offline by the clinician; the mean number of reviews per patient was 15. 192/200 (96%) RTT image reviews were in agreement with clinician review, presenting excellent concordance.Multidisciplinary involvement in training development, redesign of the TCP and inclusion of summative competency assessment were important factors to support RTT skill development. Consequently, RTT-led cervical cancer soft-tissue IGRT was clinically implemented in the hospital.

This paper describes the implementation of intensity modulated radiotherapy (IMRT) in a radiotherapy department. When preparing to set-up an IMRT programme, it is important to review departmental protocols with regard to immobilization, CT planning, treatment planning and verification. Any additional quality assurance steps also need to be fully understood. A new IMRT programme is most likely to be successful if it builds on established clinical experience with three-dimensional conformal radiotherapy (CRT). Training of radiographers, clinicians and physicists is critical, and both team-work and communication are vital to ensure a smooth transition from 3DCRT to IMRT delivery in the clinic.

We studied the rate of response to palliative external beam radiation therapy (20 Gy/5 or 30 Gy/10 fractions) to the base of skull in 32 prostate cancer patients with cranial nerve dysfunction. Sixteen patients (50%; 95% CI, 34–66%) had a useful response to therapy. The median survival post-therapy was 3 months.

A commercial active breathing coordinator (ABC) device, employed to hold respiration at a specific level for a predefined duration, was successfully adapted for magnetic resonance imaging (MRI) use for the first time. Potential effects of the necessary modifications were assessed and taken into account. Automatic MR acquisition during ABC breath holding was achieved. The feasibility of MR-ABC thoracic and abdominal examinations together with the advantages of imaging in repeated ABC-controlled breath holds were demonstrated on healthy volunteers. Five lung cancer patients were imaged under MR-ABC, visually confirming the very good intra-session reproducibility of organ position in images acquired with the same patient positioning as used for computed tomography (CT). Using identical ABC settings, good MR-CT inter-modality registration was achieved. This demonstrates the value of ABC, since application of T1, T2 and diffusion weighted MR sequences provides a wider range of contrast mechanisms and additional diagnostic information compared to CT, thus improving radiotherapy treatment planning and assessment.

<h3>Purpose</h3> Adaptive radiation therapy strategies could account for interfractional uterine motion observed in patients with cervix cancer, but the current cone beam computed tomography (CBCT)-based treatment workflow is limited by poor soft-tissue contrast. The goal of the present study was to determine if ultrasound (US) could be used to improve visualization of the uterus, either as a single modality or in combination with CBCT. <h3>Methods and Materials</h3> Interobserver uterine contour agreement and confidence were compared on 40 corresponding CBCT, US, and CBCT-US-fused images from 11 patients with cervix cancer. Contour agreement was measured using the Dice similarity coefficient (DSC) and mean contour-to-contour distance (MCCD). Observers rated their contour confidence on a scale from 1 to 10. Pairwise Wilcoxon signed-rank tests were used to measure differences in contour agreement and confidence. <h3>Results</h3> CBCT-US fused images had significantly better contour agreement and confidence than either individual modality (<i>P</i> < .05), with median (interquartile range [IQR]) values of 0.84 (0.11), 1.26 (0.23) mm, and 7 (2) for the DSC, MCCD, and observer confidence ratings, respectively. Contour agreement was similar between US and CBCT, with median (IQR) DSCs of 0.81 (0.17) and 0.82 (0.14) and MCCDs of 1.75 (1.15) mm and 1.62 (0.74) mm. Observers were significantly more confident in their US-based contours than in their CBCT-based contours (<i>P</i> < .05), with median (IQR) confidence ratings of 7 (2.75) versus 5 (4). <h3>Conclusions</h3> CBCT and US are complementary and improve uterine segmentation precision when combined. Observers could localize the uterus with a similar precision on independent US and CBCT images.

Objective: Stereotactic ablative radiotherapy (SABR) has become the standard of care for suitable patients with peripherally located early stage non-small cell lung cancer. Lung SABR requires strict image-guided radiotherapy (IGRT) protocols to ensure its safe delivery. The aim of this survey was to provide an assessment of current lung SABR practice in the UK. Methods: An online semi-structured survey containing a maximum of 32 questions regarding lung SABR, focussing on treatment image verification processes was piloted, developed and disseminated to the radiotherapy managers of 62 National Health Service centres across the UK. Results: The survey had a 100% complete response from NHS centres. 36 centres (58%) currently deliver lung SABR, with half treating fewer than 50 patients per year. Six centres deliver SABR despite not being commissioned by the NHS to provide this service. There is wide variation in the use of IGRT. Eight different permutations of cone beam CT order within the workflow were reported. Almost half of lung centres (17/36, 47%) believe there is a need to update national image guidance associated with lung SABR, such as the use of ‘day zero’, mid treatment and post treatment cone beam CTs. Conclusion: Our results demonstrate wide variation in IGRT for lung SABR. There is an opportunity to develop existing IGRT workflows and the optimal approach to image guidance. Further work is required to investigate lung SABR provision and potential barriers to its implementation. Advances in knowledge: This survey represents the most comprehensive and accurate assessment of lung SABR practice in the UK since the 2014 SABR consortium survey.

Abstract Voluntary inspiration breath hold ( VIBH ) for left breast cancer patients has been shown to be a safe and effective method of reducing radiation dose to the heart. Currently, VIBH protocol compliance is monitored visually. In this work, we establish whether it is possible to gate the delivery of radiation from an Elekta linac using the Microsoft Kinect version 2 (Kinect v2) depth sensor to measure a patient breathing signal. This would allow contactless monitoring during VMAT treatment, as an alternative to equipment–assisted methods such as active breathing control ( ABC ). Breathing traces were acquired from six left breast radiotherapy patients during VIBH . We developed a gating interface to an Elekta linac, using the depth signal from a Kinect v2 to control radiation delivery to a programmable motion platform following patient breathing patterns. Radiation dose to a moving phantom with gating was verified using point dose measurements and a Delta4 verification phantom. 60 breathing traces were obtained with an acquisition success rate of 100%. Point dose measurements for gated deliveries to a moving phantom agreed to within 0.5% of ungated delivery to a static phantom using both a conventional and VMAT treatment plan. Dose measurements with the verification phantom showed that there was a median dose difference of better than 0.5% and a mean (3% 3 mm) gamma index of 92.6% for gated deliveries when using static phantom data as a reference. It is possible to use a Kinect v2 device to monitor voluntary breath hold protocol compliance in a cohort of left breast radiotherapy patients. Furthermore, it is possible to use the signal from a Kinect v2 to gate an Elekta linac to deliver radiation only during the peak inhale VIBH phase.

<h2>Abstract</h2><h3>Background and purpose</h3> Appropriate internal margins are essential to avoid a geographical miss in intensity-modulated radiation therapy (IMRT) for endometrial cancer (EC). This study evaluated interfraction target motion using rigid and non-rigid approximation strategies and calculated internal margins based on random and systematic errors using traditional rigid margin recipes. Dosimetric impact of target motion was also investigated. <h3>Materials and methods</h3> Cone beam CTs (CBCTs) were acquired days 1–4 and then weekly in 17 patients receiving adjuvant IMRT for EC; a total of 169 CBCTs were analysed. Interfraction motion for the clinical target volume vaginal vault and upper vagina (CTVv) was measured using bony landmarks and deformation vector field displacement (DVFD) within a 1 mm internal wall of CTVv. Patient and population systematic and random errors were estimated and margins calculated. Delivered dose to the CTVv and organs at risk was estimated. <h3>Results</h3> There was a significant difference in target motion assessment using the different registration strategies (p < 0.05). DVFD up to 30 mm occurred in the anterior/posterior direction, which was not accounted for in PTV margins using rigid margin recipes. Underdosing of CTVv D95% occurred in three patients who had substantial reductions in rectal volume (RV) during treatment. RV relative to the planning CT was moderately correlated with anterior/posterior displacement (r = 0.6) and mean relative RV during treatment was strongly correlated with mean relative RV at CBCT acquired days 1–3 (r = 0.8). <h3>Conclusion</h3> Complex and extensive geometric changes occur to the CTVv, which are not accounted for in margin recipes using rigid approximation. Contemporary margin recipes and adaptive treatment planning based on non-rigid approximation are recommended.

Abstract Purpose The aim of this study was to assess the feasibility of radiographer led verification of cone-beam computed tomography (CBCT) images for patients with solitary lung tumours treated with stereotactic body radiotherapy treatment (SBRT). Material and methods CBCT setup images of 20 patients from the first fraction of each patient were retrospectively registered by therapeutic radiographers. The displacements recorded were compared with the clinical oncologist’s original online match. The time taken by radiographers to verify the CBCT images was also recorded. Results Overall agreement for all radiographers when compared with the clinical oncologist match was 91%. Interobserver variations between radiographers were X plane 0·87 (0·76–0·94); Y plane 0·74 (0·51–0·88); and Z plane 0·88 (0·78–0·95) intraclass correlation coefficient and 95% confidence interval. The average time taken for verification was 128 seconds. Conclusion Therapeutic radiographers are able to verify CBCT images for thorax SBRT with results comparable to the ‘gold standard’ clinical oncologists’ match, however additional training will be provided for online verification. The time taken was within acceptable limits.

To evaluate three image acquisition presets for four-dimensional cone beam CT (CBCT) to identify an optimal preset for lung tumour image quality while minimizing dose and acquisition time.Nine patients undergoing radical conventionally fractionated radiotherapy for lung cancer had verification CBCTs acquired using three presets: Preset 1 on Day 1 (11 mGy dose, 240 s acquisition time), Preset 2 on Day 2 (9 mGy dose, 133 s acquisition time) and Preset 3 on Day 3 (9 mGy dose, 67 s acquisition time). The clarity of the tumour and other thoracic structures, and the acceptability of the match, were retrospectively graded by visual grading analysis (VGA). Logistic regression was used to identify the most appropriate preset and any factors that might influence the result.Presets 1 and 2 met a clinical requirement of 75% of structures to be rated "Clear" or above and 75% of matches to be rated "Acceptable" or above. Clarity is significantly affected by preset, patient, observer and structure. Match acceptability is significantly affected by preset.The application of VGA in this initial study enabled a provisional selection of an optimal preset (Preset 2) to be made.This was the first application of VGA to the investigation of presets for CBCT.

To explain what a clinical academic career can be, what it can lead to for the individual, profession and most importantly the patient, and why these roles are so important to radiography.Multiple challenges to the adoption of clinical academic careers exist, including achievable measurable outcomes, visibility & senior support, and balancing different time demands. Equally the rewards are wide ranging and can advance both the individual and profession through role extension opportunities, increased career progression, patient benefits, and academic and research skills.Clinical academic careers can provide advantages for the individual, department, profession and most importantly the patient with advanced clinical practice through evidenced based research.Improving clinical academic careers within Radiography will promote research participation and increase radiographic roles in patient-centred research delivery and development. Combining evidenced based research with academic skills will lead to improved patient care and better clinical outcomes.

Objective Little is understood about the anxiety experienced by cancer patients undergoing radiotherapy or investigative imaging. Our aim was to identify sources of anxiety, the points along the cancer journey where anxiety occurred and methods to alleviate it. Methods Six focus groups were conducted with cancer patients (n = 17), caregivers (n = 3) and healthcare practitioners (HCPs; n = 10) in the radiotherapy department. Patients described specific elements in the care pathway which induced anxiety, while HCPs focused on their perception of the patient experience. Thematic analysis was used to analyse data. Results Three broad themes emerged: The Environment, The Individual and The Unknown. The physical environment of the hospital, inside the scanner for example, emerged as a key source of anxiety. The impact of cancer on patients' individual lives was significant, with many feeling isolated. The majority of participants described anxiety associated with the unknown. HCPs reported difficulty in identifying the anxious patient. Conclusions Anxiety is experienced throughout the cancer pathway. Common sources include the physical environment and the uncertainty associated with having cancer. Identifying both anxiety-inducing factors, and the anxious patients themselves, is crucial to enable targeted interventions to alleviate anxiety.

To evaluate the precision of using digitally reconstructed radiographs (DRRs) of either 3 mm or 6 mm slice separation vs. using simulator images for the setup verification of patients receiving CT planned conformal radiotherapy to the prostate. To calculate the transfer error between CT and simulator.Twenty patients were CT scanned (3 mm slice spacing/width). DRRs were generated for both 3 mm (DRR 3) and 6 mm (DRR 6) separations. DRRs and a simulator image of an anterior and a lateral field were used as reference images. Five observers matched each of the reference images to treatment images using the Theraview "Target check" facility. It was assumed that poorer images would lead to a loss of precision of field placement estimations (FPE) between observers. The study was designed to detect a difference greater than 1.5 mm(2) in the precision of image placement. The transfer error was the mean difference in the setup error derived from the DRRs and the simulation films.The precision of evaluations for simulator films and 3 mm DRRs were similar. There was a trend for the DRR 6 mm to achieve less precise results which was greatest for craniocaudal examinations (variance: simulator 1.5 mm(2), DRR6 2.8 mm(2), p = 0.17), but this did not reach statistical significance. A range of transfer errors was identified, with standard deviations ranging from 1.7 to 4.2 mm. There was evidence of a significant systematic bias in anterior craniocaudal (1.3-1.9 mm, p < 0.004) and anterior posterior (-1.9 mm, p = 0.027).The precision of setup evaluations using DRRs is similar to that achieved by using simulator fields when planning conformal prostate radiotherapy. The use of DRRs could reduce systematic errors introduced in the planning process.

To compare the accuracy of fractionated cranial radiotherapy in a standard three-point thermoplastic shell using daily online correction with accuracy in a Gill-Thomas-Cosman relocatable stereotactic frame.All patients undergoing fractionated radiotherapy for benign intracranial tumours between March 2009 and August 2010 were included. Patients were immobilised in the frame with those unable to tolerate it immobilised in the shell. The ExacTrac imaging system was used for verification/correction. Daily online imaging before and after correction was carried out for shell patients and systematic and random population set-up errors calculated. These were compared with frame patients who underwent standard departmental imaging/correction with fractions 1-3 and weekly thereafter. Set-up margins were calculated from population errors.Systematic and random errors were 0.3-0.7 mm/° before correction and 0.1-0.2 mm/° after correction in all axes in the frame, and 0.6-1.5 mm/° before correction and 0.1-0.4 mm/° after correction in the shell. Isotropic margins required for patient set-up could be reduced from 2 mm to <1 mm in the frame and from 5 mm to <1 mm in the shell.Similar set-up accuracy can be achieved in the standard thermoplastic shell as in a relocatable frame despite less precise immobilisation. The use of daily online correction precludes the need for larger set-up margins.

Objective: Cone beam CT (CBCT) enables soft-tissue registration to planning CT for position verification in radiotherapy.The aim of this study was to determine the interobserver error (IOE) in prostate position verification using a standard CBCT protocol, and the effect of reducing CBCT scan length or increasing exposure, compared with standard imaging protocol.Methods: CBCT images were acquired using a novel 7 cm length image with standard exposure (1644 mAs) at Fraction 1 (7), standard 12 cm length image (1644 mAs) at Fraction 2 (12) and a 7 cm length image with higher exposure (2632 mAs) at Fraction 3 (7H) on 31 patients receiving radiotherapy for prostate cancer.Eight observers (two clinicians and six radiographers) registered the images.Guidelines and training were provided.The means of the IOEs were compared using a Kruzkal-Wallis test.Levene's test was used to test for differences in the variances of the IOEs and the independent prostate position.Results: No significant difference was found between the IOEs of each image protocol in any direction.Mean absolute IOE was the greatest in the anteroposterior direction.Standard deviation (SD) of the IOE was the least in the left-right direction for each of the three image protocols.The SD of the IOE was significantly less than the independent prostate motion in the anterior-posterior (AP) direction only (1.8 and 3.0 mm, respectively: p 5 0.017).IOEs were within 1 SD of the independent prostate motion in 95%, 77% and 96% of the images in the RL, SI and AP direction.Conclusion: Reducing CBCT scan length and increasing exposure did not have a significant effect on IOEs.To reduce imaging dose, a reduction in CBCT scan length could be considered without increasing the uncertainty in prostate registration.Precision of CBCT verification of prostate radiotherapy is affected by IOE and should be quantified prior to implementation.Advances in knowledge: This study shows the importance of quantifying the magnitude of IOEs prior to CBCT implementation.

Stereotactic conformal radiotherapy (SCRT) is a high precision technique of fractionated radiotherapy which ensures accurate delivery of radiation with reduction in the volume of normal tissue irradiated as compared to conventional external beam radiotherapy. We describe the technique and preliminary experience of SCRT in patients with residual and recurrent pituitary adenomas.Between February 1995 and March 1999, 22 patients (mean age: 45.3, range: 20-67 years) with residual or recurrent pituitary adenomas (13 nonfunctioning, nine secretory) were treated with SCRT. All were immobilized in a relocatable Gill-Thomas-Cosman (GTC) frame and tumour was localized on a postcontrast planning computerized tomography (CT) and MRI scan. The gross tumour volume (GTV) and the critical structures were outlined on contiguous 2-3 mm separated slices. A margin of 5 mm (12 patients) to 10 mm (10 patients) was grown around GTV in three-dimensions (3-D) to generate the planning target volume (PTV). The treatment was delivered by three (five patients) and four (17 patients) maximally separated conformal fixed fields with each field conformed to the shape of the tumour using customized lead alloy blocks (19 patients) or multileaf collimator (three patients). The patients were treated on a 6-MV linear accelerator to a dose of 45 Gy in 25 fractions (18 patients) and 50 Gy in 30 fractions (four patients).The technique of SCRT has become a part of the routine work of the radiotherapy department. The treatment was well tolerated with minimal acute toxicity. One patient developed transient quadrantanopia 2 weeks after treatment with full recovery after a short course of corticosteroids. One patient had a transient visual deterioration 7 months after treatment due to cystic degeneration of the tumour which fully recovered following surgical decompression. Nine of the 15 patients presenting with visual impairment had improvement after treatment and the visual status remained stable in all others. One patient with acromegaly and one with a prolactinoma achieved normalization of elevated hormonal abnormality four and 10 months after SCRT, respectively. The remaining seven patients with a secretory adenoma had declining hormone levels at last follow-up. Newly initiated hormone replacement therapy was required in five patients. At a median follow-up of 9 months (range 1-44 months), the 1 and 2 year actuarial progression free and overall survival were 100%.Stereotactic conformal radiotherapy is a high precision technique suitable for the treatment of pituitary adenomas requiring radiotherapy. Preliminary results suggest effective tumour control and low toxicity within the range expected for conventional external beam radiotherapy. While the technique is of potential benefit in reducing the volume of normal brain irradiated, the advantages in terms of sustained tumour control and reduced toxicity over conventional radiotherapy need to be demonstrated in long-term prospective studies.

Background and purpose To investigate the feasibility and the advantages of a portal-imaging mode on a medical accelerator, consisting of a thin low-Z bremsstrahlung target and a thin Gd2O2S/film detector, for patient imaging. Patients and methods The international code of practice for high-energy photon dosimetry was used to calibrate dosimetry instruments for the imaging beam produced by 4.75 MeV electrons hitting a 6 mm thick aluminium target. Images of the head and neck of a humanoid phantom were taken with a mammography film system and the dose in the phantom was measured with TLDs calibrated for this beam. The first head and neck patient images are compared with conventional images (taken with the treatment beam on a film radiotherapy verification detector). Visibility of structures for six patients was evaluated. Results Images of the head and neck of a humanoid phantom, taken with both imaging systems showed that the contrast increased dramatically for the new system while the dose required to form an image was less than 10−2 Gy. The patient images taken with the new and the conventional systems showed that air–tissue interfaces were better defined in the new system image. Anatomical structures, visible on both films, are clearer with the new system. Additionally, bony structures, such as vertebrae, were clearly visible only with the new system. The system under evaluation was significantly better for all features in lateral images and most features in anterior images. Conclusions This pilot study of the new portal imaging system showed the image quality is significantly improved.

The aim of this article was to test a simple approach of using pixel density values from fluoroscopy images to enable gated radiotherapy.Anterior and lateral (LAT) from images were acquired from 18 patients referred for radical radiotherapy for non-small cell lung cancer for a period of 30-45 s. The amplitude of movement and the number of breathing cycles were determined in the right-left (RL) and superoinferior (SI) directions on the anterior images and the anteroposterior (AP) and SI directions on the lateral images. The breathing pattern was created by analysing the variation in a summation of pixel values within a defined area. The greatest and lowest 30% of pixel values were set as the duty cycle to represent inhale and exhale amplitude-based gating.A median of eight breathing cycles was captured for each patient with a duration of 2.2-11.8 s per cycle. The mean (range) motion was 4.7 mm (2.4-5.8 mm), 7.2 mm (2.3-17.6 mm), 6.2 mm (1.9-13.8 mm) and 4.8 mm (2.4-11.3 mm) in the RL, SI (AP), SI (LAT) and AP directions, respectively. A total of 10/14 anterior videos and 7/11 LAT videos had correlations between motion and breathing of >0.6. Margins of 5.5 mm, 6.8 mm and 6.6 mm in the RL, SI and AP directions, respectively, were determined to gate in exhale. The benefit of gating was greater when motion was >5 mm.The simple approach of using pixel density values from fluoroscopy images to distinguish inhale from exhale and enable gating was successfully applied in all patients. This technique may potentially provide an accurate surrogate for tumour position.

Keywords: radiotherapy, prostate cancer, post-prostatectomy, image-guided radiation therapy

Deep-inspiration breath-hold (DIBH) reduces radiation dose to the heart in patients undergoing locoregional breast radiotherapy. In the context of tangential irradiation of the breast/ chest wall, a voluntary breath hold (vDIBH) technique has been shown to be as reproducible as a machine-assisted breath hold technique using the active breathing co-ordinator (ABC™, Elekta, Crawley, UK, ABC_DIBH). This study compares set-up reproducibility for vDIBH versus ABC_DIBH in patients undergoing volumetric-modulated arc radiotherapy (VMAT) for breast cancer, both with and without wax bolus.Patients with breast cancer requiring pan regional lymph node VMAT +/- wax bolus in breath-hold were CT scanned in vDIBH and ABC_DIBH. Patients were randomised to receive one technique for fractions 1-7 and the other for fractions 8-15. Daily cone beam computed tomography (CBCT) was performed and registered to planning-CT using bony anatomy. Within-patient comparisons of mean daily chest wall position were made using a paired t-test. Population, systematic (∑) and random errors (α) were estimated. Intrafraction reproducibility was assessed by comparing chest wall position and diaphragm movement between consecutive breath holds on CBCT.16 patients were recruited. All completed treatment with both techniques (9 patients with wax bolus, 7 patients without). CBCT derived ∑ were 2.1-6.4 mm (ABC_DIBH) and 2.1-4.9 mm (vDIBH), α were 1.7-2.6 mm (ABC_DIBH) and 2.2-2.7 mm (vDIBH) and mean daily chest wall displacements (MD) were 0.0-1.5 mm (ABC_DIBH) and -0.1-1.6 vDIBH (all p non-significant). Chest wall and diaphragm position was equivalent between consecutive breath holds in ABC and vDIBH (median difference 1.0 mm and 0.8 mm respectively, non p significant) demonstrating equivalent intrafraction reproducibility.This study demonstrates that a simple voluntary breath hold technique is feasible in combination with VMAT (+/- bolus) and is as reproducible as ABC_DIBH with VMAT for the irradiation of the breast and axillary and IMC lymph nodes in breast cancer patients.

Imaged-guided radiotherapy (IGRT) is not a new technique; rather, it has evolved over the past few decades. It has been defined in many ways, but for the purposes of this Editorial it can be thought of as any imaging at pre-treatment and delivery, the result of which is acted upon, that improves or verifies the accuracy of radiotherapy. Although imaging at the time of treatment delivery, for example electronic portal imaging, has been available since the early 1990s, the consistency and frequency of use throughout the UK has been variable.

Introduction In the United Kingdom fiducial marker IGRT is the second most common verification method employed in radical prostate radiotherapy yet little evidence exists to support centres introducing or developing this practice. We developed a survey to elicit current fiducial marker practices adopted in the UK, to recommend standardisation of practice. Methods A 16 question survey was distributed across UK Radiotherapy centres via promotion at the British Uro-Oncology Group Conference, 2016. Included were questions relating to workforce planning, patient preparation, insertion procedure and verification methods. The survey was open from September 2016 to January 2017. Results Results from 15 centres routinely inserting fiducial markers for prostate IGRT are presented. Eleven professional groups insert fiducial markers across the UK. Fourteen centres insert fiducial markers trans-rectally; one trans-perineally. Centres adopting a trans-rectal approach administer prophylactic ciprofloxacin as a single agent or combined with gentamicin or metronidazole; poor agreement between regimes presented. One centre has introduced targeted antibiotic prophylaxis. Five brands of fiducial markers are utilised nationally. Fourteen centres standardly insert three single fiducial markers, two common configurations emerged. Coupled fiducial markers are routinely implanted by one centre. All centres delay at least one week between fiducial marker insertion and planning CT; seven centres wait two weeks. The most common fiducial verification method is two-dimensional, paired kilo Voltage imaging. Conclusion Variation in fiducial marker practice across the UK is considerable. Standardisation is required to support centres and healthcare professionals developing this service. Seven recommendations, to unify practice, have been proposed based on survey results and literature.

Image guided radiotherapy has evolved from two dimensional (2D) megavoltage imaging, which allowed verification with respect to bony anatomy, to three dimensional (3D) kilovoltage imaging which enables soft tissue structures to be used for verification. Alongside the technological developments, treatment delivery techniques have become more sophisticated and the potential to adapt treatment delivery to changes in tumour and/or organs at risk is increasing. This review explores the current status of soft tissue imaging techniques in conjunction with the potential clinical impact. The common tumour sites where the new treatment techniques are being investigated are identified and it is seen that to support the implementation of these techniques, investment in capital equipment and staff training is essential.

In response to Ms Westbrook's thoughtful publication 1 Westbook C. Opening the debate on MRI practitioner education – is there a need for change?. Radiography. 2017; 23: S70-S74 Abstract Full Text Full Text PDF Scopus (13) Google Scholar discussing the education of MRI practitioners, we agree that the current UK educational methods are failing, as depend primarily on senior MRI radiographers, who in many cases have simply learned ‘on-the-fly’ to train new radiographers, with little/no understanding of MRI safety, physics or even language, whilst maintaining a clinical service. MRI needs to be incorporated and expanded in undergraduate programs, as the application of magnetic resonance to patients is very different than X-ray and CT. We feel firmly that specialist education (in addition to enhanced content in undergraduate programs) should be required.

<h2>Abstract</h2> The MR-Linac (MRL) provides a novel treatment modality that enables online adaptive treatments, but also creates new challenges for patient positioning in a laser-free environment. The accuracy and duration of prostate patient set-up on the MRL using two different methods for patient alignment was determined to establish standard of practice on the MRL. Differences in set-up accuracy were significant in the longitudinal direction and are accounted for in online plan adaption. Both methods recorded similar set-up times. The vendor recommended alignment method involves less manipulation of the patient and will be adopted as the standard positioning method for prostate and other pelvic patients on the MRL in future.

Effective transperineal ultrasound image guidance in prostate external beam radiotherapy requires consistent alignment between probe and prostate at each session during patient set-up. Probe placement and ultrasound image interpretation are manual tasks contingent upon operator skill, leading to interoperator uncertainties that degrade radiotherapy precision. We demonstrate a method for ensuring accurate probe placement through joint classification of images and probe position data. Using a multi-input multi-task algorithm, spatial coordinate data from an optically tracked ultrasound probe is combined with an image classifier using a recurrent neural network to generate two sets of predictions in real-time. The first set identifies relevant prostate anatomy visible in the field of view using the classes: outside prostate, prostate periphery, prostate centre. The second set recommends a probe angular adjustment to achieve alignment between the probe and prostate centre with the classes: move left, move right, stop. The algorithm was trained and tested on 9,743 clinical images from 61 treatment sessions across 32 patients. We evaluated classification accuracy against class labels derived from three experienced observers at 2/3 and 3/3 agreement thresholds. For images with unanimous consensus between observers, anatomical classification accuracy was 97.2% and probe adjustment accuracy was 94.9%. The algorithm identified optimal probe alignment within a mean (standard deviation) range of 3.7° (1.2°) from angle labels with full observer consensus, comparable to the 2.8° (2.6°) mean interobserver range. We propose such an algorithm could assist radiotherapy practitioners with limited experience of ultrasound image interpretation by providing effective real-time feedback during patient set-up.

The ability of intensity-modulated radiotherapy (IMRT) to sculpt the dose distribution closely around the tumour volume has the potential to have a major impact on radiotherapy clinical practice. However, dynamic IMRT treatment delivery differs from that of conventional treatment because of the constantly moving multileaf collimators (MLCs) and higher monitor units (MUs) required. The implementation of new technology can be affected by the users response. Radiographers' attitudes regarding technology and their perceptions of the clinical implementation of IMRT were explored using a qualitative study based on semi-structured interviews. 16 radiographers were interviewed and data was analysed using a framework analysis to identify themes and categories. The majority of radiographers (12/16) demonstrated positive attitudes regarding technology. The introduction of IMRT was seen to be stimulating and motivating. Negative aspects were associated with increased stress from learning new skills and the additional pressure of the increased workload. Although there were contradictory views regarding the effect of the increased use of technology on the patient-radiographer relationship, technological skills and patient care were not found to be mutually exclusive. Radiographers' perceptions regarding the clinical implementation of IMRT appeared to be influenced by their mainly positive attitudes regarding technology. With the current problems of recruitment and retention of radiographers, full exploitation of modern technology could be used to improve job satisfaction. However, careful integration is required to balance training needs with service demands.

Image guided radiotherapy (IGRT) has been defined as ‘any imaging at the pre-treatment and treatment delivery stage that leads to an action that can improve or verify the accuracy of radiotherapy’ [[1]National Cancer Action Team National Radiotherapy Implementation Group. ‘ Image Guided Radiotherapy - Guidance for Implementation and Use’; 2012.Google Scholar]. During the last 30 years, imaging in radiotherapy has reflected the advances of technology in society. We have moved from 2D, film imaging, to digital camera imaging (electronic portal imaging), then to video recording, 3D technology (Computerised Tomography (CT) and Cone Beam CT(CBCT)), more recently the addition of 4D information with location finders, (4D CT, 4D CBCT), and now entering the world of real-time adaptive radiotherapy which promises to be a ‘global positioning system (GPS) for radiotherapy’. This special edition of Tipsro, focused on IGRT, demonstrates the developments in practice aiming to achieve greater accuracy in radiotherapy planning and delivery. The therapeutic radiographer/radiation therapist (TR/RTT’s) role has evolved alongside technologic developments and we must ensure that our education and professional development keeps apace [[2]Duffton A. Devlin L. Tsang Y. Mast M. Leech M. one behalf of the ESTRO RTTC Advanced Practice: An ESTRO RTTC position paper.TipsRO. 2019; 10: 16-19Google Scholar]. Role development and advanced practice will continue to transform as new skills become routine, and new techniques/technology emerge. It is important that we maintain education and competency to validate such skills. To improve accuracy the first step in defining the target is crucially important. Good practice in diagnostic radiography can inform radiotherapy to optimise image quality [[3]Davis A.T. Palmer A.L. Pani S. Nisbet A. Assessment of the variation in CT scanner performance (image quality and Hounsfield units) with scan parameters, for image optimisation in radiotherapy treatment planning.Phys Med. 2018; 45: 59-64Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar]. The increased use of contrast and the implementation of multimodality imaging for example Magnetic Resonance Imaging (MRI) are both illustrated in this edition. CT scanners with high specification are now commonplace in radiotherapy departments enabling the application of 4D imaging and contrast in pre- treatment imaging use where appropriate. Skills such as cannulation and administering contrast can be acquired and maintained in line with the increase in use. The integration of MRI into radiotherapy planning varies internationally but the overall trend is increasing and it is recommended in many tumour sites particularly in those with solid tumours [4Speight R. Schmidt M.A. Liney G.P. Johnstone R.I. Eccles C.L. Dubec M. et al.IPEM Topical Report: A 2018 IPEM survey of MRI use for external beam radiotherapy treatment planning in the UK.Phys Med Biol. 2019; 64Crossref PubMed Scopus (14) Google Scholar, 5Dirix P. Haustermans K. Vandecaveye V. The value of magnetic resonance imaging for radiotherapy planning.Semin Radiat Oncol. 2014 Jul; 24: 151-159Crossref PubMed Scopus (91) Google Scholar, 6Paganelli C. Whelan B. Peroni M. Summers P. Fast M. van de Lindt T. et al.MRI-guidance for motion management in external beam radiotherapy: current status and future challenges.Phys Med Biol. 2018; 63Crossref PubMed Scopus (76) Google Scholar]. The recent introduction of MR Linac systems, combining MR imaging and a linear accelerator, further integrates MRI with radiotherapy. Knowledge of safety in MRI, MR image acquisition and optimisation will be required by TR/RTT’s both pre and post registration [[7]Eccles C.L. McNair H.A. Armstrong S.E.A. Helyer S.J. Scurr E.D. In response to Westbrook- Opening the debate on MRI practitioner education.Radiography (Lond). 2017; 23: S75-S76Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar]. Reproducible patient positioning throughout treatment must be investigated in parallel with developments in IGRT imaging. Breath hold is good example of a technique that is an effective method of reproducing the position of the target and becoming more widely used [[8]Boda-Heggemann J. Knopf A.C. Simeonova-Chergou A. Wertz H. Stieler F. Jahnke A. et al.Deep inspiration breath hold-based radiation therapy: a clinical review.Int J Radiat Oncol Biol Phys. 2016; 94: 478-492Abstract Full Text Full Text PDF PubMed Scopus (149) Google Scholar]. However it is imperative that the benefit and reproducibility of immobilisation techniques are investigated both generally and in each department when implemented. Image verification has progressed from assessing bony anatomy, to the use of surrogates and/or soft tissue assessment. The role of the TR/RTT has become vital when implementing techniques such as stereo tactic body radiotherapy, where a high dose is delivered daily. To avoid the need for a clinician to be present at each fraction, training and competency programmes can be undertaken by the TR/RTTs [[9]Hudson J. Doolan C. Locke I. McDonald F. Ahmed M. Gunapala R. et al.Are Therapeutic Radiographers able to achieve clinically acceptable verification for stereotactic lung radiotherapy treatment (SBRT)?.J Radiother Pract. 2015; : 10-17Crossref Scopus (7) Google Scholar]. The involvement of, and communication with, the multi-disciplinary team is essential when developing these programmes [[10]McNair H.A. Hafeez S. Taylor H. Lalondrelle S. McDonald F. Hansen V.N. et al.Radiographer-led plan selection for bladder cancer radiotherapy: initiating a training programme and maintaining competency.Br J Radiol. 2015; 88: 1048Crossref Scopus (31) Google Scholar]. Audit is an important tool which can be used to assess the efficacy of such training programmes, the development of which can be iterative, and is nicely illustrated here. Adaptive radiotherapy is the next evolution and encompasses, replanning off-line during the course of treatment, defining a library of plans for choice prior to treatment and real time on-line replanning [[11]Keall P. Poulsen P. Booth J.T. See, think, and act: real-time adaptive radiotherapy.Semin Radiat Oncol. 2019; 29: 228-235Crossref PubMed Scopus (28) Google Scholar]. Off-line planning requires definition of thresholds for re-planning to be identified and a process established. Although practical solutions have been presented [[12]Kwint M. Conijn S. Schaake E. Knegjens J. Rossi M. Remeijer P. et al.Intra thoracic anatomical changes in lung cancer patients during the course of radiotherapy.Radiother Oncol. 2014; 113: 392-397Abstract Full Text Full Text PDF PubMed Scopus (96) Google Scholar], practice in department remains variable, as often the case with many new processes [[13]Beasley M. Brown S. McNair H. Faivre-Finn C. Franks K. Murray L. et al.The advanced radiotherapy network (ART-NET) UK lung stereotactic ablative radiotherapy survey: national provision and a focus on image guidance.Br J Radiol. 2019; 92PubMed Google Scholar]. Hence this areas remains a topic of investigation and two papers in this edition investigate off-line adaptive radiotherapy which again highlights the importance of the TR/RTT in this process. Real time on-line adaptive radiotherapy could be considered as GPS for radiotherapy; adapting the journey to reach the destination depending on the situation of the surroundings each day. It is only recently that this has been clinically possible with the introduction of the MR Linac, although treatments are lengthy and resource intensive [14Lamb J. Cao M. Kishan A. Agazaryan N. Thomas D.H. Shaverdian N. et al.Online adaptive radiation therapy: implementation of a new process of care.Cureus. 2017; 9: e1618PubMed Google Scholar, 15Corradini S. Alongi F. Andratschke N. Belka C. Boldrini L. Cellini F. et al.MR-guidance in clinical reality: Current treatment challenges and future perspectives.Radiat Oncol. 2019; 14https://doi.org/10.1186/s13014-019-1308-Crossref Google Scholar] compared to conventional C-arm radiotherapy. However, with the treatment planning times becoming faster [16Ziegenhein P. Pirner S. Ph Kamerling C. Oelfke U. Fast CPU-based Monte Carlo simulation for radiotherapy dose calculation.Phys Med Biol. 2015; 60: 6097-6111Crossref PubMed Scopus (26) Google Scholar, 17van Dijk L.V. Van den Bosch L. Aljabar P. Peressutti D. Both S. Steenbakkers R.J.H.M. et al.Improving automatic delineation for head and neck organs at risk by Deep Learning Contouring.Radiother Oncol. 2019; Google Scholar] and automation of aspects of planning eg contouring, it is possible that adaptive on-line treatments will be possible on C-arm Linacs. For an efficient workflow the role of each discipline, oncologist, physicists and TR/RTT, needs to be reviewed and established. Radiographer/radiation therapists are the key professionals at the patient technology interface in the radiotherapy pathway and must continue to investigate and assess efficacy and efficient of new technologies. We acknowledge NHS funding to the NIHR Biomedical Research Centre at The Royal Marsden and The Institute of Cancer Research. The views expressed in this publication are those of the authors and not necessarily those of the NHS Executive. Helen McNair is funded by a National Institute for Health Research and Health Education England (HEE/NIHR), Senior Clinical Lecturer award.