Cystic peritoneal mesothelioma: report of a case.

Benign multicystic peritoneal mesothelioma (BMPM) is a rare disease with good short-term prognosis and rare malignant transformation. However, its biological significance remains unexplained. A neoplastic origin is considered by many authors to require a surgical excision, based on the high recurrence and progressive growth rate of the tumors. However, alternative or integrative treatment options have also been proposed. A 45-year-old woman presented to our unit with a history of occasional discomfort and pain in the left hip. On physical examination, we noticed a tough-elastic, fixed mass located in the iliac fossa. Computed tomography scan detected a mass with multiseptated cystic-like areas. Due to the similarity of these findings to a primitive sarcomatous tumor of the retroperitoneum, an arteriographic study was also performed. The patient underwent en bloc resection of the mass, including a segment of the sigmoid colon. The final pathologic diagnosis was cystic mesothelioma. Further studies are needed to better understand the etiology and pathogenesis of this rare disease, and to define a more tailored treatment plan.