High-grade prostatic intraepithelial neoplasia.

High-grade prostatic intraepithelial neoplasia (HGPIN) has been established as a precursor to prostatic adenocarcinoma. HGPIN shares many morphological, genetic, and molecular signatures with prostate cancer. Its predictive value for the development of future adenocarcinoma during the prostate-specific antigen screening era has decreased, mostly owing to the increase in prostate biopsy cores. Nevertheless, a literature review supports that large-volume HGPIN and multiple cores of involvement at the initial biopsy should prompt a repeat biopsy of the prostate within 1 year. No treatment is recommended for HGPIN to slow its progression to cancer.