High-grade prostatic intraepithelial neoplasia on a prostate biopsy-what does it mean?

Investigators in the field of urology, oncology, and pathology have been attempting to unravel the mystery of early diagnosis, treatment, and monitoring of men with prostate cancer for several decades. Recently a great deal of attention has been focused on obtaining a better understanding, both pathologically as well as clinically, of the pre-malignant lesion of prostatic intraepithelial neoplasia. Although not diagnostic of prostate cancer on a needle biopsy, many morphologic, molecular, histopathological, epidemiological, and genetic studies have offered strong evidence that high-grade prostatic intraepithelial neoplasia (HGPIN) is in fact a precursor lesion to development of invasive prostatic adenocarcinoma. Early studies in the literature that first characterized this relationship suggested that histologic evidence of HGPIN on a prostate biopsy predicted a nearly 50% risk of finding prostate cancer on a subsequent prostate biopsy. Through the years, much larger, prospective, population-based studies have suggested that this likelihood is more in the range of 25% to 30%. Knowing that the likelihood of finding prostate cancer after a “negative prostate biopsy” ranges between 10% and 25% if a repeat biopsy were performed brings into question the need or clinical utility of recommending immediate repeat prostate biopsy when HGPIN is seen on initial prostate biopsy.