Predictors of Gleason score upgrading in patients with prostate biopsy Gleason score ≤6

Abstract

Introduction: The discrepancy between prostate biopsy and prostatectomy Gleason scores is common. We investigate the predictive value of prostate biopsy features for predicting Gleason score (GS) upgrading in patients with biopsy Gleason scores =6 who underwent radical retropubic prostatectomy (RRP). Our aim was to determine predictors of GS upgrading and to offer guidance to clinicians in determining the therapeutic option. Methods: We performed a retrospective study of patients who underwent RRP for clinically localized prostate cancer at 2 major centres between January 2007 and March 2013. All patients with either abnormal digital examination or elevated prostate-specifi antigen at screening underwent transrectal ultrasound-guided prostate biopsy. Variables were evaluated among the patients with and without GS upgrading. Our study limitations include its retrospective design, the fact that all subjects were Turkish and the fact that we had a small sample size. Results: In total, 321 men had GS =6 on prostate biopsy. Of these, 190 (59.2%) had GS=6 concordance and 131 (40.8%) had GS upgrading from =6 on biopsy to 7 or higher at the time of the prostatectomy. Independent predictors of pathological upgrading were prostate volume <40 cc (p < 0.001), maximum percent of cancer in any core (p = 0.011), and >1 core positive for cancer (p < 0.001). Conclusions: When obtaining an extended-core biopsy scheme, patients with small prostates (=40 cc), greater than 1 core positive for cancer, and an increased burden of cancer are associated with increased risk of GS upgrading. Patients with GS =6 on biopsy with these pathological parameters should be carefully counselled on treatment decisions.