Diagnosis of limited adenocarcinoma of the prostate

This article provides an overview of the diagnosis of limited prostate cancer on needle biopsy. A few of the more common mimickers of prostate cancer, such as adenosis, partial atrophy, and high-grade prostatic intraepithelial neoplasia, are also covered. A systematic approach to diagnosing prostate cancer by evaluating architectural, nuclear, intraluminal and ancillary features is presented. The use of immunohistochemistry, including its pitfalls and limitations, is described and illustrated. By the use of a systematic diagnostic approach as outlined in this article, the threshold for diagnosing limited carcinoma of the prostate can be decreased. If a pathologist is not comfortable in diagnosing carcinoma in a particular small focus, this review will help them to recognize these foci as atypical and suspicious for carcinoma, so that further workup might lead to a more definitive diagnosis. Some of the more common situations leading to an atypical diagnosis have also been presented to help prevent the overdiagnosis of prostatic malignancy.