Early oncological outcomes of robot‐assisted radical prostatectomy for high‐grade prostate cancer

Abstract

OBJECTIVE: To evaluate the oncological outcomes of patients with specimen Gleason 8 and 9 prostate cancers and to determine factors that predict biochemical recurrence-free survival (BCRFS) after robot-assisted radical prostatectomy (RARP). PATIENTS AND METHODS: Of 4156 patients who underwent RARP from January 2001 to 2009, we identified 368 men with Gleason 8 or 9 tumours who met the inclusion criteria. BCR was defined as a PSA level of ≥0.2 ng/mL with a second rising value. The Kaplan-Meier method and log-rank test were used to compare BCRFS while factors that predict BCRFS were determined by Cox proportional hazards modelling. RESULTS: The median age and PSA level were 62 years and 6.4 ng/mL for men with Gleason 8, and 63 years and 6.7 ng/mL for Gleason 9 cancers. The median (interquartile range, IQR) overall follow-up was 23 (10-46) months and 19 (7-37) months for Gleason 8 and 9 tumours, respectively. At 60 months the mean (se) overall BCRFS was 36 (5)% and for Gleason 8 it was 47 (6)% and for Gleason 9 it was 21 (7)% (P < 0.001). At 5 years, extraprostatic extension (pT3a) resulted in BCRFS of 52 (9)% for Gleason 8 tumours and 21 (11)% for Gleason 9 (P= 0.012). On multivariable analysis, lymph node invasion, specimen Gleason score, pathological stage and tumour volume predicted BCRFS. CONCLUSIONS: Early results suggest RARP monotherapy performs comparably to RP for BCRFS in men with high-grade prostate cancer. There are significant oncological differences between Gleason 8 and 9 tumours.