Reply to vitamin D status may explain racial disparities in survival among patients with advanced renal cell carcinoma in the targeted therapy era.

BACKGROUND Historically, African American (AA) patients with renal cell carcinoma (RCC) have had inferior survival compared with Caucasian patients. Recent studies suggest that the survival disparity between races may be worsening since the advent of targeted therapies for RCC. In this study, survival rates among AA and Caucasian patients with advanced RCC are examined over time to determine whether a disparity in survival persists in the targeted therapy era. METHODS The authors identified patients with stage IV RCC in the National Cancer Data Base and compared survival between AA and Caucasian patients during the periods before (1998-2004) and after (2006-2011) the advent of targeted therapy. RESULTS In total, 48,846 patients were identified, and 10% were AA. Three-year survival among both AA and Caucasian patients improved between the 2 periods (P < .01 for both), with no interaction observed between race and improved survival over time (P = .15). The adjusted hazard ratio (HR) for death among AAs compared with Caucasians was 1.13 (95% confidence interval, 1.08-1.19) in the post-targeted therapy era, which was unchanged from the pretargeted therapy era (adjusted HR, 1.10; 95% confidence interval, 1.04-1.15). The adjusted HR was similar when the analysis was restricted to those who received systemic therapy. CONCLUSIONS Both AA and Caucasian patients with advanced RCC have had a significant improvement in survival since the advent of targeted therapy. However, AA patients maintain a survival disadvantage compared with Caucasians independent of treatment received, potentially related to unmeasured comorbidities, disease burden, or tumor biology. Cancer 2016;122:2988-2995. © 2016 American Cancer Society.