Association of Health-Care System with Prostate Cancer-Specific Mortality in African American and Non-Hispanic White Men.

BACKGROUND Disparities in prostate cancer-specific mortality (PCSM) between African American and non-Hispanic White (White) patients have been attributed to biological and systemic factors. We evaluated drivers of these disparities in the Surveillance, Epidemiology and End Results (SEER) national registry and an equal-access system, the Veterans Health Administration (VHA). METHODS We identified African American and White patients diagnosed with prostate cancer between 2004-2015 in SEER (N = 311,691) and the VHA (N = 90,749). We analyzed the association between race and metastatic disease at presentation using multivariable logistic regression adjusting for sociodemographic factors, and PCSM using sequential competing-risks regression adjusting for disease and sociodemographic factors. RESULTS The median follow-up was 5.3 years in SEER and 4.7 years in the VHA. African American men were more likely than White men to present with metastatic disease in SEER (adjusted odds ratio = 1.23, 95% confidence interval [CI] = 1.17-1.30), but not in the VHA (adjusted odds ratio = 1.07, 95% CI = 0.98-1.17). African American versus White race was associated with an increased risk of PCSM in SEER (subdistribution hazard ratio [SHR] = 1.32, 95% CI = 1.10-1.60), but not in the VHA (SHR = 1.00, 95% CI: 0.93-1.08). Adjusting for disease extent, PSA, and Gleason score eliminated the association between race and PCSM in SEER (aSHR 1.04, 95% CI 0.93-1.16). CONCLUSIONS Racial disparities in PCSM were present in a nationally representative registry, but not in an equal-access healthcare system, due to differences in advanced disease at presentation. Strategies to increase healthcare access may bridge the racial disparity in outcomes. Longer follow-up is needed to fully assess mortality outcomes.Disparities between African American and non-Hispanic White (White) patients in cancer-specific mortality have been described across numerous cancer types and healthcare systems[1-5]. The survival gap between African American and White patients with prostate cancer has been well-characterized, with two-fold higher prostate cancer-specific mortality (PCSM) rates among African American patients depending on the setting[1, 6-10]. This disparity has been attributed to differences in prostate cancer biology in African American men, in addition to systemic factors in mediating this disparity, such as differential access to healthcare, Prostate-Specific Antigen (PSA) screening, and distrust in the healthcare system[1, 11-16].The Veterans Health Administration (VHA) is a relatively equal-access healthcare system that treats a large, ethnically diverse population of veterans. The Surveillance, Epidemiology and End Results (SEER) program is a national cancer registry program that collects data from the general United States (US) population. The goals of the present investigation were to 1) Compare PCSM between African American and White men within SEER and the VHA and 2) Identify modifiable system-level contributors to these disparities. We hypothesized that PCSM would be comparable among African American and White men in an equal-access setting, the VHA, but not in a national registry, SEER, and that this disparity in SEER would be in part driven by more advanced disease at presentation.