Biochemical recurrence (BCR) following radical prostatectomy (RP) is an unreliable predictor of prostate cancer (PC) progression. This study was a retrospective cohort analysis of prospectively collected data (407/1895) of men with BCR at a tertiary referral center. Patients were assessed for active observation (AO) compared with a treatment group (TG) utilizing doubling time (DT) kinetics. Risk assessment was based on the initial DT (>12 vs. <12 months), then based on the DT pattern (changed over time). Those with unstable, rapidly decreasing DTs received treatment. Those with increasing and slowly decreasing DTs prompted observation. The primary outcome was PC mortality, safety, and efficacy of observations based on DT kinetics. The secondary outcome was BCR patients managed with or without treatment. The median follow-up was 7.5 years (IQR 3.9−10.7). The PCSM in TG and AO was 10.7% and 0%, respectively (p < 0.001). The initial DT was >12 months in 73.6% of AO versus 22.6% of TG (p < 0.001). An increasing DT pattern was observed in 71.5% of AO versus 32.7% of TG (p < 0.001). Utilizing the Cleveland Clinic’s PCSM nomogram, at 10 years, predicted and observed PCSM was 8.6% and 9.5% (p = 0.78), respectively. In conclusion, one-third of patients with BCR post-RP were managed without treatment using DT kinetics, avoiding treatment-related complications, quality-of-life issues, and expenses.
Keywords: androgen deprivation therapy; biochemical recurrence; hormonal therapy; prostate cancer; radiation therapy; salvage therapy.