[Pseudomyxoma peritonei associated with splenic mucinous epithelial cysts--case report].

A massive gelatinous ascites occurred in a 60-year-old patient, with no primary tumor found in the clinical work-up. The malignant cells were not found in the cytological examination of ascites. Explorative laparotomy revealed a gelatinous mass of 14 kg, a cystic tumor of the omentum and an identical cystic tumor of the spleen's lower pole. It was a well differentiated mucinous cystadenocarcinoma, most likely originating in the appendix. Most interesting is the involvement of the spleen with mucinous epithelial cysts, described as a rare finding associated with pseudomyxoma.