Characteristics and outcome of prostate cancer patients with overall biopsy Gleason score 3 + 4 = 7 and highest Gleason score 3 + 4 = 7 or > 3 + 4 = 7

Aim: Prostate cancer heterogeneity and multifocality might result in different Gleason scores (GS) at individual biopsy cores. According to World Health Organisation/International Society of Urologic Pathology (WHO/ISUP) guidelines, the GS in each biopsy core should be recorded with optional reporting of overall GS for the entire case. We aimed to compare the clinicopathological characteristics and outcome of men with overall biopsy GS 3 + 4 = 7 with highest GS 3 + 4 = 7 (HI = OV) to those with highest GS > 3 + 4 = 7 (HI > OV).
Methods and results: Prostate cancer biopsies from the European Randomised Study of Screening for Prostate Cancer (ERSPC) were revised according to WHO/ISUP 2014 guidelines (n = 1031). In total, 370 patients had overall GS 3 + 4 = 7, 60 of whom (16%) had had at least one biopsy core with GS 4 + 3 = 7 or 4 + 4 = 8. Men with higher GS than 3 + 4 (HI > OV) in any of the cores had higher age, prostate-specific antigen (PSA) level, number of positive biopsies, percentage tumour involvement, percentage Gleason grade 4 and cribriform or intraductal growth (all P < 0.05) than those with GS 3 + 4 = 7 at highest (HI = OV). In multivariable Cox regression analysis, including PSA, percentage positive biopsies and percentage tumour involvement, biochemical recurrence-free survival after radical prostatectomy (P = 0.52) or radiotherapy (P = 0.35) was not statistically different between both groups.
Conclusion: Among patients with overall GS 3 + 4 = 7, those with highest GS > 3 + 4 = 7 had worse clinicopathological features, but clinical outcome was not statistically significant. Therefore, the use of overall GS instead of highest GS for clinical decision-making is justified, potentially preventing overtreatment in prostate cancer patients.