Prognosis of a rare subtype of thyroid cancer: Spindle cell thyroid carcinoma.

Systemic illustrations of spindle cell thyroid cancer (SCTC), based on a large cohort, are few. We investigated the prognosis of SCTC compared to the most common subtypes, papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC). Information of patients with a diagnosis of SCTC, PTC, or FTC, between 2004 and 2013, was obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Patient survival curves were investigated using Kaplan-Meier analyses, log-rank tests, and Cox proportional hazards regression analyses. In a Kaplan-Meier analysis of the entire cohort of thyroid cancer patients, cancer specific survival declined sharply for patients with SCTC, but declined more modestly for patients with PTC and FTC. Unadjusted Cox regression analysis and Kaplan-Meier curve analysis showed that SCTC had a poorer cancer-specific mortality and all-cause mortality compared to PTC and FTC. Similar results were obtained after adjustment for different confounding factors. Our study assessed the prognosis of SCTC, based on a large cohort, compared to PTC and FTC, and found relatively accurate hazard ratios of death rate in SCTC as compared to PTC and FTC. Thus, our findings would provide beneficial insights on patients with SCTC, and aid in treatment decision making, more radical treatment like total-thyoridectomy and/or plus central lymph node dissection should be performed for patients with SCTC.