Long-Term Results of Treatment of 283 Patients with Lung and Bone Metastases from Differentiated Thyroid Carcinoma

We assessed the results of treatment in 283 patients with lung or bone metastases from differentiated thyroid carcinoma who were followed for up to 40 yr (median, 44 months) after the discovery of the metastases. The survival rates from the time of discovery of the metastases were 53% at 5 yr, 38% at 10 yr, and 30% at 15 yr; 156 patients died. Multivariate analysis revealed that only 4 variables had an independent prognostic significance for survival. They were extensive metastases, older age at discovery of the metastases, absence of radioiodine uptake by the metastases, and moderately differentiated follicular cell type. The site of metastases (lung or bone) was not a prognostic factor for survival after treatment of metastatic disease. Remission was achieved in 79 patients after metastases were found. The only predictive factor for 5-yr disease-free survival after treatment of metastases was the initial extent of disease. Our results suggest that the aim of management should be to detect and treat metastases in patients with thyroid cancer as early as possible.