Cytoprotection for Radiation-Associated Normal Tissue Injury

One of the cornerstones of radiation therapy is the delivery of therapeutic radiation doses to the target tissue, yet minimization of dose to surrounding normal tissue. In practice, there is always some dose delivered to surrounding normal tissue. Pure restriction of dose to the target volume, without any incidental irradiation of normal tissue, is physically impossible for most situations. Furthermore, the normal tissue effects of radiation are typically increased when concurrent chemotherapy and radiotherapy (RT) are used [1]. Concurrent chemoradiotherapy has been demonstrated to be superior, with regard to local control and/or survival, compared to single modality alone [2], in multiple disease sites such as the head and neck [3–6], lung [7–10], and pelvis [11–15]. Therefore, it is incumbent upon physicians to do what is possible to minimize the risks associated with incidental irradiation of normal tissues.