A Case of Encapsulating Peritoneal Sclerosis Complicated by Malignant Peritoneal Mesothelioma.

We report a case of peritoneal mesothelioma discovered in a patient during peritoneal dialysis. The patient was a 55-year-old woman who had no history of asbestos exposure. Owing to end-stage kidney failure, she had been undergoing peritoneal dialysis for over 8 years, and she had been diagnosed with encapsulating peritoneal sclerosis. She was admitted to the hospital for intestinal obstruction. Three months later, she noticed an enlarging mass in the epigastric region. Computed tomography showed a 10-cm mass originating in the abdominal wall that had invaded the liver. It was diagnosed as malignant mesothelioma via biopsy. Cases of sarcoma-like mass-forming peritoneal mesothelioma are rare, and there are no prior reports of encapsulating peritoneal sclerosis complicated by malignant peritoneal mesothelioma. Thus, this unique case of peritoneal mesothelioma can provide us with important knowledge about this rare entity.