Is high grade prostatic intraepithelial neoplasia still a risk factor for adenocarcinoma in the era of extended biopsy sampling?

Methods: Pathological findings from PNBs from 12 304 men who underwent initial PNB during an 8 year period were analysed. Patients were included in the study if their initial diagnosis was HGPIN alone or a benign diagnosis, if at least one follow-up PNB was performed, and if both the initial and follow-up PNB contained at least 10 prostate cores. Results: In the benign group of 105 patients and the HGPIN group of 120 patients, 14.1% and 20.8% were diagnosed with prostatic adenocarcinoma, respectively. When the HGPIN group was further subdivided into unifocal (1 core) and multifocal (>= 2 cores) groups, 9.4% and 29.9% developed prostatic adenocarcinoma, respectively (p < 0.0001). Cox regression analysis adjusting for age and prostate specific antigen (PSA) confirms the significance of HGPIN as a risk factor for prostatic adenocarcinoma (p = 0.0045). Conclusions: Patients with an initial diagnosis of multifocal HGPIN on extended PNB are at a greater risk for subsequent prostatic adenocarcinoma than those with unifocal HGPIN or benign diagnoses.