[Factors of Treatment Efficacy in Salvage Radiotherapy without Concomitant Hormonal Therapy for Biochemical...

This study investigated the factors associated with the success of salvage radiotherapy (SRT) defined as PSA reaching less than 0.2 ng/ml without concomitant hormonal therapy after biochemical recurrence (BCR) following radical prostatectomy (RP). The study included 38 patients who underwent robot-assisted radical prostatectomy (RARP) and received SRT alone from 2015 to 2021. Patients with prior treatments, those who underwent hormonal therapy, patients whose PSA did not decrease to less than 0.2 ng/ml after RARP, and pN1 cases were excluded. The median age and PSA at the start of SRT were 68 years and 0.26 ng/ml, respectively, and positive surgical margins were observed in 14 cases (37%). The median follow-up time from the start of SRT was 36.1 months, and 52.6% of the cases achieved SRT success with SRT alone. Multivariate analysis demonstrated that pre-SRT PSA ＜0.25 ng/ml and positive surgical margins were significantly different between SRT success cases and non-SRT success cases.