The Comparative Outcomes of Radical Prostatectomy versus Radiotherapy for Nonmetastatic Prostate Cancer: A Longitudinal, Population-Based Analysis.

PURPOSE: The comparative effectiveness of radical prostatectomy (RP) versus radiation therapy (RT) for prostate cancer remains a largely debated topic. Utilizing a provincial population-based linked data set from an equal-access, universal health care system, we sought to compare outcomes among patients treated with either radiation or prostatectomy for nonmetastatic prostate cancer. MATERIALS AND METHODS: We performed a retrospective cohort study by linking several administrative data sets to identify patients who were diagnosed with prostate cancer between 2004 and 2016 in Manitoba, Canada and who were subsequently treated with either RP or RT. Cox proportional hazard models with inverse probability of treatment weighting were used to compare rates of all-cause mortality, as well as prostate cancer specific mortality (PCSM) between patients who underwent RP vs RT. RESULTS: During the study period, 2,540 patients underwent RP and 1,895 underwent RT for prostate cancer. Unadjusted overall survival was higher for RP vs RT (5-year overall survival 95.52% for RP compared with 84.55% for RT, p <0.0001). In inverse probability of treatment weighting-adjusted Cox regression analysis, compared to patients in the RP groups, patients in the RT group had an increased rate of all-cause mortality (HR 1.93, 95% CI 1.65-2.26, p <0.0001), and PCSM (HR 3.98, 95% CI 2.89-5.49; p <0.0001). CONCLUSIONS: RT was associated with higher all-cause mortality and PCSM rates compared with RP. These findings highlight the importance of comparative effectiveness research to identify treatment disparities and warrant further investigation.