Replacement of the uterus by malignant mesothelioma of the periteneum: A case report

Malignant mesothelioma of the peritoneum is a rare tumor that must be disti nguished from the more common primary peritoneal serous epithelial neoplasm s. We report a case of a 66-year-old female presenting with weight loss, an emia, and a large pelvic mass on ultrasound. At laparotomy a large (9x6.5x3 .5 cm) mass in the anatomical position of the uterus was found in the minor pelvis. The uterus, tubes and ovaries could not be identified. Palpable pa raaortic lymph nodes and liver nodules were found. Immunohistochemic ally the tumor cells were positive for cytokeratin, epith elial membrane antigen and vimentin-CEA, but S-100 protein and Leu-M1 were negative. Remnants of the uterine corpus, fallopian tubes and ovaries could not be id entified. The overall features were best regarded as malignant peritoneal m esothelioma. There have been reports of mesotheliomas involving the uterus. However, thi s is the first reported case of mesothelioma causing total replacement of t he uterus.