Longer time to testosterone recovery impacts favorably on outcomes for prostate cancer following androgen deprivation and radiotherapy.

ABSTRACT

PURPOSE: To evaluate the impact of sustained hypogonadism after androgen deprivation therapy (ADT) associated with radiotherapy in prostate cancer (PCa) patients with biochemical relapse-free survival (bRFS). METHODS: A retrospective cohort analysis of 213 consecutive PCa patients referred for radiotherapy plus ADT was carried out. Follow-up times including time to testosterone recovery (TTR) and bRFS were calculated from the end of ADT. Univariate and multivariate Cox regression analyses predicting bRFS were used. The optimal cutoffs for TTR and duration of ADT were determined using the maximally selected rank statistics (MSRS). RESULTS: After a median follow-up of 104 months, 18 patients relapsed among those who had recovered testosterone levels and 9 among those who did not. Median ADT duration was 36 months. The optimal cutoff for TTR was determined using MSRS. TTR >48 months was significantly associated with better bRFS (logrank, p < 0.0027). Five-year bRFS was 100% for >48 months vs. 85% for <48 months. TTR was the only significant variable for bRFS in multivariate Cox analysis. CONCLUSION: Our data show an association between longer TTR and bRFS values among PCa patients treated with ADT.