Prostate cancer after initial high-grade prostatic intraepithelial neoplasia and benign prostate biopsy

Limited data exist on long term pathological outcomes in patients with initial prostate biopsies showing either high-grade intraepithelial neoplasia (HGPIN) or benign findings, who are subsequently diagnosed with prostate cancer.

Preoperative characteristics of patients showing either HGPIN or benign initial prostate biopsies were investigated and compared in patients with and without a subsequent diagnosis of prostate cancer. We also compared the biopsy and prostatectomy findings in patients with prostate cancer in both groups.

We evaluated 161 and 85 patients with initial HGPIN and benign prostate biopsies, respectively, who underwent a subsequent biopsy. After a median follow up of 11 years, prostate cancer was detected in 26.7% patients after HGPIN and in 22.3% patients after initial benign biopsy. Ninety-eight percent of positive biopsies after initial HGPIN demonstrated either Gleason score (GS) 3 + 3 (86%) or GS 3 + 4 (12%). In the benign group, 100% of patients demonstrated prostate cancer on biopsy with either GS 3 + 3 (58%) or GS 3 + 4 (42%). Of 35 patients who underwent prostatectomy (22 after initial HGPIN biopsy and 13 after initial benign biopsy), all had node negative, organ-confined disease; 86% and 54% patients had GS6 disease, with = 5% tumor volume found in 91% and 62% of the HGPIN and benign group, respectively.

Patients with initial HGPIN or benign biopsies preceding a diagnosis of prostate cancer usually show favourable pathology on positive biopsy and prostatectomy, most commonly exhibiting low volume and low grade disease. These findings may help clinicians risk-stratify patients who may benefit from conservative management options.