Morphological identification of the patterns of prostatic intraepithelial neoplasia and their importance

High grade prostatic intraepithelial neoplasia (PIN) is the most likely pre cursor of prostatic carcinoma. PIN has a high predictive value as a marker for carcinoma, and its identification in biopsy specimens warrants repeat b iopsy for concurrent or subsequent carcinoma. The only methods of detection are biopsy and transurethral resection; PIN does not greatly raise the con centration of serum prostate specific antigen (PSA) or its derivatives, doe s not induce a palpable mass, and cannot be detected by ultrasound. Androge n deprivation decreases the prevalence and extent of PIN, suggesting that t his form of treatment might play a role in chemoprevention. Radiotherapy is also associated with a decreased incidence of PIN.