Significance of high-grade prostatic intraepithelial neoplasia on prostate biopsy

The early diagnosis of prostate cancer has been facilitated by the development of serum prostate-specific antigen (PSA) testing and evolution in transrectal ultrasound-guided biopsy of the prostate. Over a decade has passed since the initial recommendations for systematic sextant sampling of the prostate to increase the accuracy of cancer detection. Subsequently, variations in the number and location of biopsies have been proposed to maximize prostate cancer detection and obtain more complete information regarding tumor grade, tumor volume, and local stage. Although current biopsy strategies provide a wide sampling of the prostate gland, biopsy histology may not be conclusive for either the presence or absence of adenocarcinoma. High-grade prostatic intraepithelial neoplasia (HGPIN) is found in a significant fraction of patients undergoing transrectal prostate biopsies. In this article, we discuss the significance of high-grade prostatic intraepithelial neoplasia and other abnormal histology findings and current evidence addressing the presence of cancer and need for additional prostate biopsies.