Management and outcomes of Gleason six prostate cancer detected on needle biopsy: A single-surgeon experience over 6 years

Abstract

Objective: To assess the management and oncological outcomes in men diagnosed with Gleason score (GS) 6 prostate cancer on needle biopsy in a regional centre, as compared with published international data. Materials and methods: A retrospective analysis was conducted of patients who were diagnosed with GS 6 prostate cancer via transrectal ultrasound-guided or transperineal biopsy between June 2009 and September 2015 under the care of a single surgeon. Data were obtained from a prospectively collected database. Results: A total of 166 patients were diagnosed with GS 6 prostate cancer. The mean age was 61 (range 46-79) years, with mean prostate-specific antigen of 6.7 (0.91-26.8) ng/mL at diagnosis. Of 166 patients, 117 (70.5%) patients were enrolled into the active surveillance program with 82 (70%) meeting Prostate Cancer Research International Active Surveillance (PRIAS) criteria, 44 patients underwent immediate definitive treatment (88.6% radical prostatectomy and 9.1% radiotherapy) and five watchful waiting. With a median follow-up of 1.8 years, 37 (31.6%) patients on AS had definitive treatment [30 cases (81%) were attributable to disease progression, 4 cases (10.8%) to an abnormal magnetic resonance imaging result and 3 cases (8.1%) for patient preference]. In the 35 patients who underwent radical prostatectomy immediately after diagnosis, the GS was >/=7 in 29 cases (82.9%), and the final pathology was pT3a in 16 (51.6%) and pT3b in one (2.9%). In patients who underwent radical prostatectomy after being on AS, the proportion of GS >/=7 prostate cancer was 29/32 (90.6%), with pT3a in six (18.8%) and pT3b in three (9.4%) cases. Overall, 23.5% of patients had a multiparametric magnetic resonance imaging scan. Conclusion: This single-surgeon cohort of GS 6 prostate cancer patients demonstrates a high proportion of cases managed with active surveillance, with comparable rates to international literature. The majority of cases who underwent immediate definitive treatment had significant disease, indicating that patients are being appropriately selected for active surveillance.