Purpose: We investigated oncological outcomes in Japanese patients who underwent robot-assisted radical prostatectomy (RARP).
Materials and methods: This study included 389 patients who underwent RARP at a single institution with a follow-up period of at least 1 year. Preoperative findings were compared with biochemical recurrence (BCR). Predictors of BCR-free survival (BCRFS) were evaluated by univariate and multivariate Cox proportional hazard model analyses, and a risk stratification model based on the relative risks of BCR was established.
Results: Fifty incidences of BCR were noted during a median follow-up period of 28.7 months (range, 12.1-80.0 months). The BCRFS rate for the entire cohort at the median follow-up time was 85.9 %; the 1-, 3-, and 5-year estimates were 91.0, 85.1, and 81.1 %, respectively. From univariate analyses, prostate-specific antigen (PSA), PSA density, biopsy Gleason score, and percent positive core were significantly associated with BCR. Multivariate analysis showed that PSA [hazard ratio (HR), 2.75; p = 0.001], percent positive core (HR, 2.22; p = 0.001), and biopsy Gleason score (HR, 2.61; p = 0.007) were independent predictors of BCR.
Conclusion: This study at a single Japanese center demonstrates that RARP provides a satisfactory BCRFS rate. This report provides a framework with which to estimate oncological outcomes in patients who underwent RARP for localized prostate cancer. Our results support the increased use of RARP for the treatment of localized prostate cancer in Japan.