Long-Term Prognosis and Treatment Strategy of Persistent PSA After Radical Prostatectomy.

PURPOSE: Prostate-specific antigen (PSA) is thought to be undetectable (< 0.1 ng/mL) after radical prostatectomy (RP), and persistent PSA (≥ 0.1 ng/mL) is considered a failure of curative treatment. MATERIALS AND METHODS: The study population consisted of 135 patients, all of whom underwent RP for localized prostate cancer, and developed persistent PSA. We set the starting point at the timing of RP, and the endpoints were the development of castration-resistant prostate cancer (CRPC) and cancer-specific survival. RESULTS: Salvage radiation therapy (RT) and androgen deprivation therapy (ADT) were performed in 53 (39.3%) and 64 (47.4%) patients, respectively. Eighteen (13.3%) patients didn't receive any salvage treatment. During the median follow-up of 10.1 years, CRPC was observed in 23 patients, and 6 patients died due to prostate cancer. Kaplan-Meier curves demonstrated the 15-year CRPC-free and cancer-specific survivals were 79.5% and 92.7%, respectively. Cox multivariate analysis demonstrated that seminal vesicle invasion (SVI) (p = 0.007) and nadir PSA ≥1.0 ng/mL (p = 0.002) were independent risk factors for CRPC. Salvage RT demonstrated better cancer control (the 10-and 15-year CRPC-free survival was 94.1% and 94.1%) compared to ADT (75.9% and 58.5%, p = 0.017) after 1:1 propensity score matching. CONCLUSIONS: SVI and nadir PSA ≥1.0 ng/mL are independent risk factors for CRPC in patients with persistent PSA after RP. Salvage RT is considered to be the optimal treatment for this condition.