Significant racial differences in the incidence and behavior of the follicular variant of papillary thyroid carcinoma

Background: Increased detection of papillary thyroid cancer (PTC) has led to overtreatment of the largely indolent follicular variant (fvPTC). To guide management of non-aggressive lesions, we investigated whether race predicts PTC variant and tumor behavior. Methods: Analysis of 258 973 patients from the National Cancer Database diagnosed with PTC in 2004-2014. Clinical and tumor information was compared by race. Multivariate logistic regression was used to predict fvPTC, extrathyroidal extension (ETE), and lymph node metastasis (LNM) of fvPTC. Results: Blacks had the highest fvPTC rate (40% vs white 30%, Hispanic 26%, Asian 25%, P <.001). Blacks had higher odds of fvPTC (aOR = 1.33, 95% CI: 1.28-1.37) and lower odds of ETE than whites (aOR = 0.90, 95% CI: 0.82-0.99) (P <.001). Hispanics and Asians had lower odds of fvPTC (aOR = 0.89, 95% CI: 0.86-0.92 and aOR = 0.81, 95% CI: 0.79-0.84) and higher odds of LNM and ETE than whites (P <.001). Conclusions: Racial disparities in fvPTC incidence and behavior should be considered to optimize diagnosis and treatment planning.