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

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.