Review ArticlesVariants and Unusual Patterns of Prostate Cancer Clinicopathologic and Differential Diagnostic ConsiderationsFine, Samson W. MDAuthor Information Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY The author has no funding or conflicts of interest to disclose. Reprints: Samson W. Fine, MD, Department of Pathology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Room C505, New York, NY 10065 (e-mail: [email protected]). Advances In Anatomic Pathology: July 2012 - Volume 19 - Issue 4 - p 204-216 doi: 10.1097/PAP.0b013e31825c6b92 Buy Metrics Abstract Beyond the typical acinar morphology observed in the majority of prostatic adenocarcinomas, a spectrum of morphologic variants and prostate cancer subtypes exists. These unusual entities may be classified as: (1) cancer morphologies arising by divergent differentiation of prostatic ductal, acinar, or basal cells and associated with unique clinical features and/or therapeutic approaches, and (2) histologies occurring in the context of usual prostatic adenocarcinoma that may result in diagnostic misinterpretation or difficulties in Gleason grade assignment, especially in limited samples. This article details a number of variants, with emphasis on diagnostic criteria, differential diagnoses, and clinical significance. Copyright © 2012 Wolters Kluwer Health, Inc. All rights reserved.