Introduction: Racial and ethnic disparities in prostate cancer (PCa) mortality are partially mediated by inequities in quality of care. Intermediate- and high-risk PCa can be treated with either surgery or radiation. We sought to assess the magnitude of race-based differences in cancer-specific survival between these treatment modalities. Methods: NHB and non-Hispanic White (NHW) men with localized intermediate- and high-risk PCa, treated with surgery or radiation between 2004 and 2015 in the Surveillance, Epidemiology and End Results database were included in the study. Follow up was to December 2018. Unadjusted Kaplan-Meier curves and adjusted Fine-Gray competing-risks regression analyses with other cause of death as competing event, were employed to compare cancer-specific survival by race and treatment modality. A model with an interaction term between race and treatment was used to assess whether the type of treatment amplified or attenuated the effect of race on prostate cancer-specific mortality (PCSM). Results: 15,178 (20,1%) NHB and 60,225 (79.9%) NHW men were included in the study. NHB men had a higher cumulative incidence of PCSM (p=0.005 by log-rank test) and were significantly less likely to be treated with surgery than NHW men (aOR:0.53, 95%CIs:0.51–0.55, p<0.001). In the adjusted models, NHB men were not significantly more likely to die for PCa compared to NHW men (aHR:1.11, 95%CIs:0.97-1.27, p=0.123); while radiation was associated with a significantly higher odds of PCSM (aHR:2.03, 95%CIs:1.79-2.31, p<0.001) compared to surgery. Finally, the interaction between race and treatment on PCSM was not significant (pint=0.073), meaning that no race-based differences in PCSM were found within each treatment modality. Indeed, we found no significant difference in PCSM when comparing NHB vs. NHW men treated with surgery (aHR:1.25, 95%CIs:0.97–1.63, p=0.086) or radiation (aHR:0.95, 95%CI:0.82–1.11, p= 056). Conclusions: NHB and NHW men managed with the same treatment achieved similar PCa survival outcomes in a large national cancer registry. The higher tendency for NHB men to receive radiation was similar in magnitude to the difference in cancer survival between racial and ethnic groups. SOURCE OF Funding: None
