LAUSR

BACKGROUND Cavernous hemangiomatosis in the liver and spleen has been reported, but it occurs less commonly in the peritoneum. Here we report a case of peritoneal cavernous hemangiomatosis and share some valuable information about this disease. CASE SUMMARY A 57-year-old Chinese man had a huge abdominal mass with abdominal distention and a significant reduction of food consumption. An enhanced abdominal and pelvic computed tomography and positron emission tomography–computed tomography revealed multiple cystic masses on the peritoneum, greater omentum, small intestinal mesentery and the surface of the spleen, and a high maximum standardized uptake value of the largest cystic lesion. Exploratory laparotomy was performed, and multiple cystic masses were found on the surface of the peritoneum, greater omentum, mesentery of the small intestine, and surface of the liver and spleen. Dark red bloody cystic fluid was present in the cystic tumor. Pathological examination showed that in the stromal components, the irregular vascular wall was thin. The vessel lumen was interlinked, and the lumen was lined with flat endothelium. According to the intraoperative findings and pathologic results, the patient was diagnosed with peritoneal cavernous hemangiomatosis. CONCLUSION The possibility of peritoneal cavernous hemangiomatosis should be considered when multiple cystic masses are found in the abdominal cavity by preoperative examination.