RESUMO
BACKGROUND: Multicystic mesothelial cyst is a rare, and usually benign, tumor which is rarely diagnosed preoperatively due to the poor specificity of its symptomatology. METHODS: We report the case of a 63-year-old man with multiple comorbidities (e.g. cryptogenic cirrhosis, chronic heart failure) and a history of surgical resection of a giant abdominal cyst, who complained of recurrent intermittent abdominal pain and vomiting that appeared several weeks before. Abdominal computed tomodensitometry (CT) revealed multiple diffusely localized cysts in the abdominal cavity, ranging from 30 mm to 210 mm. RESULTS: The patient underwent surgical resection of twelve intra-abdominal cysts, identified at final pathology as benign mesothelial cysts, which were probably a recurrence following the previous surgery for a single intra-abdominal cyst. Three months later, the patient recurred with development of two new intraperitoneal cysts, with an increasing volume on CT at last follow-up (18 months). Surveillance was recommended given the patient's comorbidities and the absence of symptoms. CONCLUSIONS: Surgical resection is the treatment of choice for multicystic peritoneal mesothelioma, a rare disease that should be considered more as a borderline tumor than a benign tumor, given the high risk of recurrence and possible malignant transformation.