Long-term oncological and functional outcomes support use of low-dose-rate brachytherapy with or without external beam radiation in young men (≤60 years) with localized prostate cancer

PURPOSE: To evaluate the oncological and functional outcomes of young men treated with low-dose-rate brachytherapy (BT) for prostate cancer (PCa). MATERIALS AND METHODS: 423 men aged ≤60 years with clinically localized PCa were treated with BT ± external beam radiation. Biochemical failure was defined by Phoenix criteria. Freedom from biochemical failure (FFbF) and cancer-specific survival (CSS) at 10 and 15 years were estimated by the Kaplan–Meier method with the log-rank test to compare outcomes between National Comprehensive Cancer Network risk groups. The Cox proportional hazards model was used to determine significant predictors for FFbF and CSS. RESULTS: Median followup was 9.9 years (range, 5.1–21.7). Median age was 57 years (range, 39–60), and median prostate-specific antigen was 6.1 ng/mL (range, 0.8–71). Overall, 10- and 15-year FFbF rates were 89% and 88%; 10- and 15-year CSS rates were 99% and 98%. Increasing disease risk was associated with lower FFbF and CSS (p < 0.0001). Biologically effective dose (p < 0.0001) and use of external beam radiation (p = 0.005) were significantly associated with higher FFbF. In men potent before BT, 64% (151/237) had preserved erectile function at a median 10.2 years. There was no significant difference between treatment groups with respect to long-term urinary function (p = 0.56). CONCLUSIONS: Younger men treated with BT experience excellent long-term PCa control with low rates of treatment-related toxicity.