FRIDAY, June 14, 2019 (HealthDay News) -- After adjustment for nonbiological differences, black race is not associated with worse prostate cancer-specific mortality among men with nonmetastatic prostate cancer, according to a study published online May 23 in JAMA Oncology.
Robert T. Dess, M.D., from the University of Michigan in Ann Arbor, and colleagues evaluated the association of black race with long-term prostate cancer survival outcomes among men with nonmetastatic prostate cancer. Data were used from the Surveillance, Epidemiology, and End Results U.S. population registry (SEER; 296,273 patients; 17.8 percent black), five equal-access regional medical centers within the Veterans Affairs health system (VA; 3,972 patients; 38.1 percent black), and four pooled National Cancer Institute-sponsored Radiation Therapy Oncology Group phase 3 randomized clinical trials (RCT cohort; 5,854 patients; 19.3 percent black).
The researchers found that in the SEER cohort, black race was associated with an increased age-adjusted prostate cancer-specific mortality (PCSM) hazard (subdistribution hazard ratio [sHR], 1.30; 95 percent confidence interval [CI], 1.23 to 1.37; P < 0.001). Ten years postdiagnosis and after inverse probability weighting adjustment, black race was associated with a 0.5 percent increase in PCSM (sHR, 1.09; 95 percent CI, 1.04 to 1.15; P < 0.001). There was no significant difference for high-risk men (sHR, 1.04; 95 percent CI, 0.97 to 1.12; P = 0.29). In the VA cohort, there were no significant differences in PCSM (sHR, 0.85; 95 percent CI, 0.56 to 1.30; P = 0.46). In the RCT cohort, black men had a significantly lower hazard (sHR, 0.81; 95 percent CI, 0.66 to 0.99; P = 0.04). Other-cause mortality was significantly higher among black men in the SEER (sHR, 1.30; 95 percent CI, 1.27 to 1.34; P < 0.001) and RCT (sHR, 1.17; 95 percent CI, 1.06 to 1.29; P = 0.002) cohorts when adjusting for other variables.
"In this study, after adjustment for nonbiological differences, notably access to care and standardized treatment, black race did not appear to be associated with inferior stage-for-stage PCSM," the authors write.