Prostate cancer at the peripheral end of a prostate biopsy specimen as assessed by a novel marking technique may indicate increased risk of locally advanced disease

The objective of this study was to test a novel technique of processing a prostate biopsy (PB) specimen by marking its peripheral end (PE) as a predictive tool for locally advanced prostate cancer (PC) or margin-positive resection (R1) after radical prostatectomy (RP). Prospective evaluation of a consecutive cohort of men who underwent PB and subsequent RP was carried out. Transrectal ultrasound-guided 10–20 core PB was performed according to a standardized protocol. Each biopsy core was inked at the PE and classified as PE positive or negative. The study cohort comprised 100 men with a mean age of 62.3 years (41–75 years). Overall, PE-positive cores were found in 71 men, postoperative tumour (pT)3/pT4 stages were diagnosed in 33 men and R1 status in 45 men after RP. In univariate analysis, the presence of at least one PE-positive core was correlated to an increased risk for pT3/pT4 stage (relative risk (RR): 3.15; 95% confidence interval (95% CI): 1.1–9.9; P =0.03) and R1 status (RR: 2.9; 95% CI: 1.1–7.5; P =0.03). In multivariate analysis including Gleason score, total number of positive cores, PE positivity and PSA, PE positivity was correlated to pT3/pT4 stage ( P =0.04). In conclusion, PC at the PE of a PB specimen predicts non-organ-confined tumour stage in subsequent prostatectomy. This simple, new technique may contribute to increasing the accuracy of risk stratification for curative treatment of PC.