Diagnosis of prostatic intraepithelial neoplasia in whole mount sections of prostates.

Dysplasia of prostate or prostatic intraepithelial neoplasia (PIN) is associated with prostatic adenocarcinoma, which is quite common in elderly males. The presence of high grade PIN in biopsy of patients with clinically suspicious tumors is an indication of further search for malignancy. Whole mount sections of 48 prostates were studied. PIN was sought and graded. The morphology of other lesions including atrophy, adenosis and basal cell hyperplasia, and also seminal vesicle epithelium was studied. All 36 prostates resected for treatment of prostatic adenocarcinoma contained foci of PIN. The differential diagnosis of PIN, atrophy, adenosis, basal cell hyperplasia and seminal vesicle epithelium is quite easy when whole mount sections are studied. Whole mount sections of prostates are valuable teaching material for pathologists.