Optimal timing of hormonal therapy for prostate-specific antigen recurrence after radical prostatectomy

The present study was undertaken to examine biochemical progression in patients who received salvage hormonal therapy (HT) for biochemical disease recurrence (BCR) after radical prostatectomy (RP), and to determine the optimal timing for the administration of HT. The study population consisted of 156 patients who underwent RP and received salvage HT for BCR. The starting point of this study was the timing of RP, and the endpoint was biochemical prostate-specific antigen (PSA) progression (castration-resistance) after HT. The mean follow-up period after surgery was 8.1 years. First, we excluded 18 patients with persistent PSA (≥0.2 ng/mL) after RP from an analysis below because their prognoses were significantly poorer compared with 138 patients whose PSA nadirs had reached <0.2 ng/mL. Multivariate analysis demonstrated that Gleason score ≥8 (p = 0.010, hazard ratio (HR) 3.02), and PSA doubling time (PSA-DT) <6 months (p = 0.001, HR 7.39) was independently associated with subsequent biochemical progression after HT. Using these two variables (Gleason score and PSA-DT), we could stratify patients into three risk groups for BCR after salvage HT. Regarding the optimal timing for HT administration for these high-risk patients with both risk factors (relative risk = 22.3), the PSA cutpoint of 1.0 ng/mL at the initiation of HT showed a significant difference in progression-free survival rates (p = 0.023). The findings indicated that for high-risk patients, salvage HT for BCR after PSA nadir (<0.2 ng/mL) should be started before the PSA level exceeds 1.0 ng/mL; otherwise, there is a significant risk of subsequent biochemical progression after HT.