Association of Socioeconomic Status and Race/Ethnicity With Treatment and Survival in Patients With Medullary Thyroid Cancer

IMPORTANCE: Medullary thyroid cancer (MTC) is a relatively rare neoplasm of the thyroid but accounts for 14% of thyroid cancer–related deaths. Female sex, young age, and stage at presentation have been found to predict survival and treatment. However, patterns of survival and treatment by socioeconomic status and race/ethnicity have not been fully described. OBJECTIVE: To determine whether socioeconomic status and race/ethnicity are associated with survival and treatment in patients with MTC. DESIGN, SETTING, AND PARTICIPANTS: Data for 1647 patients with MTC from January 1, 1998, to December 31, 2011, in the Surveillance, Epidemiology, and End Results (SEER) Program registry were examined. Data analysis was conducted from June 1, 2013, to July 31, 2014. MAIN OUTCOMES AND MEASURES: Differences in receipt of thyroidectomy and lymph node examination by race/ethnicity were examined using logistic regression models. Overall and disease-specific survival were examined by race/ethnicity using Kaplan-Meier survival curves and adjusted Cox proportional hazards regression models. RESULTS: Of the 1647 patients with MTC were 1192 white (72.4%), 139 black (8.4%), 222 Hispanic (13.5%), and 94 other races/ethnicities (5.7%). Of these, 1539 (93.4%) underwent surgical treatment. There were no differences in receipt of thyroidectomy by race/ethnicity; however, black patients (adjusted odds ratio, 0.61; 95% CI, 0.39-0.93) and female patients (adjusted odds ratio, 0.76; 95% CI, 0.59-0.99) were less likely to undergo lymph node examination compared with non-Hispanic white and male patients. Black patients had lower overall (adjusted hazard ratio, 2.40; 95% CI, 1.45-3.98) and disease-specific survival (adjusted hazard ratio, 2.9; 95% CI, 1.64-5.14) compared with non-Hispanic white patients. CONCLUSIONS AND REVELANCE: In this population-based study of patients with MTC, black patients were less likely to have lymph node examination following surgery. Furthermore, Hispanic and black patients had poorer overall and disease-specific survival compared with non-Hispanic white patients after accounting for clinical factors. Racial/ethnic disparities exist in the type of treatment as well as outcomes in patients with MTC.