AMR SeriesParatesticular Mesothelioma. Report of a Case With Comprehensive Review of LiteratureBisceglia, Michele MD*; Dor, David Ben MD†; Carosi, Illuminato MD*; Vairo, Matteo PhD*; Pasquinelli, Gianandrea MD‡Author Information *Department of Pathology, IRCCS Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo ‡Department of Clinical, Radiological and Cytohistopathological Sciences, University of Bologna, Bologna, and Istituto Nazionale Biostrutture e Biosistemi, Rome, Italy †Department of Pathology, The Barzilai Medical Center, Ashkelon, Israel Referral Sources: First International AMR Symposium in Anatomic Pathology-case number 2 (slides labelled 17249-0), contributed by M. Bisceglia, MD, San Giovanni Rotondo, Italy. Reprints: Michele Bisceglia, MD, Department of Pathology, IRCCS “Casa Sollievo della Sofferenza” Hospital, V.le Cappuccini, I-71013 San Giovanni Rotondo, Italy (e-mail: [email protected]; [email protected]). All figures can be viewed online in color at http://www.anatomicpathology.com Advances in Anatomic Pathology: January 2010 - Volume 17 - Issue 1 - p 53-70 doi: 10.1097/PAP.0b013e3181c66fbc Buy Metrics Abstract Paratesticular mesotheliomas are rare tumors with 223 cases described so far. The sole plausible causative factor so far ascertained in the pathogenesis of these tumors is asbestos, which however is found in only around 30% to 40% of such cases. The age range of affected individuals is wide, mostly adults and the elderly, but also includes young people and children. The most common presenting symptom is either hydrocele of unknown origin or intrascrotal mass. When hydrocele is the presenting symptom, these tumors are often clinically overlooked and the diagnosis is delayed. Most paratesticular mesotheliomas arise in the tunica vaginalis, but primary tumors of the spermatic cord and epididymis are also on record. Tumors arising from the peritoneal mesothelium of a hernia sac are excluded from this group. The correct diagnosis is almost always made after histologic examination of the operative specimen. Immunohistochemistry and electron microscopy are always helpful and sometimes necessary tools for diagnosis. So far very few cases have been identified or suspected preoperatively on cytologic examination. Three clinicopathologic types of malignant mesotheliomas of the male genital tract are recognized: diffuse tubulo-papillary mesothelioma, well-differentiated papillary mesothelioma, and multicystic mesothelioma. The histologic subtypes are almost always pure epithelial or biphasic. The differential diagnosis is mainly with serous papillary tumors arising from Mullerian vestiges, but several diverse primary or secondary tumors also need to be considered. A clinicopathologic evaluation of a case of tunical diffuse mesothelioma in a 74-year-old male from the AMR Series is the starting point for this general review. © 2010 Lippincott Williams & Wilkins, Inc.