Survival and prognostic factors of radioiodine refractory pulmonary metastatic differentiated thyroid carcinoma (DTC).

6093 Background: The challenging key point of management of radioiodine refractory DTC patients is to define those who could benefit from experimental drugs in clinical trials. Methods: We reviewed clinical and pathological data of patients with refractory pulmonary metastatic DTC treated in our center from 1990 to 2011. Survival was estimated with the method of Kaplan-Meier. Associated prognostic factors were studied in Cox model based analyses. Results: Among 167 pulmonary metastatic DTC, 46% (n=76) met a criterion of radioiodine refractory disease: at least one metastases without I131 uptake: 61% (n=46); progressive disease despite I131: 22% (n=17) and absence of complete response despite a cumulated dose >600mCi: 17% (n=13). There were 63% of female (n=48) and the median age was 64 years (range 18-87). The initial treatment was total thyroidectomy in 92% (n=70), lymph node dissection in 71%, (n=54) and radioiodine therapy in 100% of patients. Pathological features were papillary histology in 61% (n=46...