Well-differentiated papillary mesothelioma of the peritoneum: A pathological analysis and review of the literature

Background. Well-differentiated papillary mesothelioma (WDPM) of the peritoneum is a rare subtype of peritoneal epithelioid mesothelioma which typically has low malignant potential. It most commonly occurs in young women lacking a history of asbestos exposure. Only 38 female patients with peritoneal WPDM have been reported in the literature, and no uniform treatment recommendation has been established. Case report. A 74-year-old asymptomatic woman without significant past medical history underwent workup and subsequent surgery for an adnexal mass with a normal serum CA-125 level. Exploratory laparotomy identified an ovarian serous cystadenoma and an incidental multifocal peritoneal neoplasm with extensive calcifications. Histology and cytology confirmed WDPM with extensive, intimately associated mesothelial cystic inclusions and zonal calcifications with osseous metaplasia. Our patient did not receive adjuvant therapy and was without clinical or radiologic evidence of disease 12 months after diagnosis. Conclusion. WDPM of the peritoneum in women is frequently asymptomatic and associated with an indolent course. Patient outcomes are usually favorable after tumor-debulking surgery without adjuvant therapy.