Hyperplasia of mesonephric remnant, epididymal type: A case report

Abstract

Mesonephric rests or mesonephric remnants are vestiges of embryonic structures called mesonephric (wolffian) ducts. It usually can be seen in the lateral wall of the cervix uteri. In males, the mesonephric remnants are seen in epididymis and efferent ductules. Prostate is one of the rare locations, on which the mesonephric remnants can be found. Hyperplasia of mesonephric remnants of prostate is rare but important because sometimes it is difficult to differentiate from adenocarcinoma. The lesion is important in the differential diagnosis from the high grade prostatic intraepithelial neoplasia. Here, we report an additional case of mesonephric hyperplasia, epididymal type, in a 66-year-old man. Microscopically, it showed tubular structures lined by columnar cells with pseudostratified elongated hyperchromatic nuclei. The cells showed negative reaction on high molecular weight cytokeratin and prostate-specific antigen immunostain. © 2009 The Korean Society for Cytopathology, The Korean Society for Legal Medicine, The Korean Society of Oral and Maxillofacial Pathology, The Korean Society of Pathologists, The Korean Society of Toxicological Pathology, The Korean Society of Veterinary Pathology and Blackwell Publishing Asia Pty Ltd.