Diffuse Peritoneal Malignant Mesothelioma Presenting with Abnormal Uterine Bleeding: Case Report.

This report describes a highly unusual case of malignant peritoneal mesothelioma (MPM), who presented with abnormal menstrual bleeding due to diffuse infiltration of the uterus. MPM is a rare entity, which on initial clinical presentation can be indistinguishable from a primary gynecological malignancy such as ovarian cancer. As differential diagnosis is challenging among primary care physicians, gynecologists, gynecological oncologists, and pathologists, misdiagnosis and subsequent mismanagement are not uncommon. Immunohistochemical stains were required in our case to help to make the final diagnosis. We included multiple mesothelial markers such as calretinin, CK5/6, WT-1, and D240 in our analysis, in addition to epithelial markers such as Claudin-4, BerEP4, B72.3, and PAX-8, to exclude metastatic adenocarcinoma.