Is repeat biopsy for isolated high-grade prostatic intraepithelial neoplasia necessary?

Numerous studies have cited the positive predictive value of isolated highgrade prostatic intraepithelial neoplasia (HGPIN) to the detection of cancer. Epidemiological, morphological, and molecular data support the potential for malignant transformation of HGPIN, yet no current method can discriminate which lesions will progress to clinically significant prostate cancer versus more latent lesions. Recent analyses of multiple retrospective studies have found similar rates of cancer detection following either diagnosis of isolated HGPIN or an initial negative biopsy. This may reflect increased use of extended biopsy techniques involving 10 or more cores rather than the true ability of HGPIN to undergo malignant transformation. This article discusses controversies surrounding management of an isolated diagnosis of HGPIN and whether repeat biopsy of HGPIN should be mandatory or selective in the context of other predictive values such as rising prostate-specific antigen or lesion on digital rectal examination.