Risk factors associated with disease-specific mortality in papillary thyroid cancer patients with distant metastases.

PURPOSE Papillary thyroid carcinoma (PTC) is among the most curable cancer types. Even though uncommon, some patients present distant metastatic disease at diagnosis or during the follow-up and most of them have long-term survival. However, there continues to be controversies regarding what clinicopathological features are associated with mortality in these patients. This paper evaluates the factors related to poor disease-specific survival (DSS) in patients with metastatic PTC. METHODS A retrospective cohort study included PTC patients with distant metastasis from a tertiary public oncological center. Clinicopathological features, treatment modalities, and outcome were reviewed. RESULTS Between 1986 and 2014, 108 patients were diagnosed with metastatic PTC. In the multivariate analysis male sex (HR = 2.65; 95%CI: 1.08-6.53; P = 0.033), radioiodine refractory disease (HR = 9.50; 95%CI: 1.23-73.38; P = 0.031) and metastasis at multiple sites (HR = 5.91; 95%CI: 1.80-19.32; P = 0.003) were independent risk factors for death in patients with metastatic PTC. CONCLUSION Male patients with metastatic PTC, with radioiodine refractory disease and metastasis at multiple sites have a high risk of death.