A Case of Malignant Peritoneal Mesothelioma Mimicking Mesenteric Panniculitis

Abstract

We report a rare case of malignant peritoneal mesothelioma without evident exposure to asbestos, which mimicked mesenteric panniculitis. A 66-year-old male patient was admitted to another hospital with fever and abdominal pain. Laboratory data revealed slightly elevated white blood cell count and C-reactive protein. Abdominal computed tomography showed a focal increase in density of the mesenteric fat. According to the clinical symptoms and these findings, he was diagnosed with mesenteric panniculitis and treated with antibiotics and fasting. Because he repeated hospitalization for the same symptoms three times in half a year, the steroids therapy was considered. In order to rule out malignancy, he was referred to our hospital for laparoscopic mesenteric biopsy. The diagnostic laparoscopy findings included many small yellowish white nodules in the entire peritoneum, small quantities of ascites, and the slightly thickened omentum which adhered to the abdominal wall. A part of the omentum was resected and ascites was collected for cytodiagnosis. Histological examination of the resected specimen showed proliferating malignant epithelioid cells that stained strongly for calretinin, which was compatible with malignant peritoneal mesothelioma. Malignant peritoneal mesothelioma is a rare malignancy. It is difficult to diagnose because clinical symptoms and findings are nonspecific. We recommend that malignant peritoneal mesothelioma should be included in the differential diagnosis of patients with mesenteric panniculitis, though it is rare.