High-grade prostatic intraepithelial neoplasia with adjacent atypia is associated with a higher incidence of cancer on subsequent needle biopsy than high-grade prostatic intraepithelial neoplasia alone

Objectives. High-grade prostatic intraepithelial neoplasia (HGPIN) is often considered a premalignant lesion of the prostate. Its incidence ranges fro m 0.7% to 20% in all prostate biopsies, and patients with HGPIN on initial biopsy are reportedly found to have a higher risk of cancer on subsequent b iopsy. The purpose of our study was to determine the incidence of HGPIN in our patients who underwent prostate biopsy and to determine whether a furth er pathologic subclassification of HGPIN between HGPIN atone and HGPIN with adjacent atypical glands has any prognostic value in predicting the rate o f prostate cancer on subsequent prostate biopsy. Methods. A total of 485 patients who underwent prostate biopsy between Janu ary 1998 and October 1999 were included in the study. Each set of slides wa s reviewed by a single urologic pathologist to determine the presence of HG PIN alone or HGPIN with adjacent atypical glands. If any HGPIN was identifi ed, a repeat biopsy was performed, and the presence of cancer was recorded. Results. The overall incidence of HGPIN alone and HGPIN with adjacent atypi cal glands on initial biopsy was 33 (6.8%) of 485. Of these 33 patients, 21 (64%) had HGPIN alone and 12 (36%) had HGPIN with adjacent atypical glands . Three (14%) of 21 patients with HGPIN alone were found to have cancer on subsequent biopsy compared to 9 (75%) of 12 patients with HGPIN with adjace nt atypia on initial biopsy. This difference is statistically significant ( P < 0.005). Conclusions. The incidence of HGPIN alone in our experience is 4.3% (21 of 485). Patients with HGPIN with adjacent atypical glands suspicious for canc er have a significantly higher incidence of cancer on subsequent biopsy tha n patients with HGPIN alone. UROLOGY 57: 296-300, 2001. (C) 2001, Elsevier Science Inc.