Purpose: Unequal access to health care may be a reason for shorter survival among Black patients with renal cell carcinoma (RCC) than among their White counterparts. No studies have investigated survival disparity among RCC patients in an equal-access health care delivery system. This study aimed to examine racial differences in survival among clear cell RCC patients in the Department of Defense's (DoD) Military Health System (MHS), which provides equal access to care to all persons.
Methods: The study used the DoD's Automated Central Tumor Registry to identify 2056 White patients and 370 Black patients diagnosed with clear cell RCC between 1988 and 2004. The subjects were followed through 2007 with a median follow-up time of 4.8 years. Kaplan-Meier survival curves were compared and a Cox model was used to estimate the hazard ratios (HRs) associated with survival by race.
Results: During follow-up, 1,027 White and 158 Black patients died. The Kaplan-Meier curves showed that Black patients had more favorable overall survival than did White patients (log rank p = 0.031). After adjustment for demographic, tumor, and treatment variables, the Cox model showed no statistically significant racial difference overall (adjusted HR 1.07, 95 % CI 0.90-1.28) or stratified by age, sex or tumor stage. However, among patients who did not undergo surgery, Black patients had poorer survival than White patients.
Conclusions: The lack of racial difference in survival among RCC patients in the MHS may be related to equal access to health care. Improved access could reduce the survival disparity among RCC patients in the general population.