Basal cell hyperplasia (BCH) versus high grade prostatic intraepithelial neoplasia (HGPIN) in tiny prostatic needle biopsies: Unusual diagnostic dilemma.

BACKGROUND Histopathological differentiation between BCH and HGPIN in prostatic needle biopsies is a diagnostic challenge. The gold standard for detection of HGPIN and BCH is histopathological examination; however subjectivity in interpretation and tiny volume of obtained tissue hamper reliable diagnosis. AIMS The aim of this study was to assess usefulness of using the p63 and p504s to solve this problem. Although the use of p63 and p504s is now well established in differentiation between preneoplastic and neoplastic prostatic lesions, their usefulness in tiny tissue material is, however, not fully studied. METHODS The study included a spectrum of 30 prostatic needle biopsies (5 BCH, 10 HGPIN, 10 indefinite luminal proliferations where BCH and HGPIN could not be distinguished from each other and 5 adenocarcinomas). H&E stained sections were examined for histopathological features. Other sections were stained immunohistochemically with p63 and p504s. RESULTS The mean age of patients was 69 (SD=7.6) years. PSA range was 1.3-2.7 ng/ml. Ultrasongraphic findings were unremarkable. All BCH showed p504s-/p63+ pattern, All HGPIN had p504s+/p63+ pattern while carcinomas were p504s+/p63-. After immunostaining combined with histopathological features; the 10 indefinite specimens could be diagnosed as 4 BCH and 6 HGPIN. The article explains how applying this staining pattern on the challenging specimens, combined with histopathological features, can be helpful in proper identification of prostatic proliferations.