Low-grade mucinous cystadenocarcinoma in the spleen.

A 69-year-old man with an enlarged spleen, found by computed tomography scan to be multicystic, underwent a splenectomy. Pathological examination revealed a Low-grade mucinous cystadenocarcinoma that was histologically analogous to a mucinous tumor of the ovary. The serum level of tumor markers carcinoembryonic antigen (CEA)and CA19-9 were elevated preoperatively and returned to normal after the operation. In the absence of a primary tumor elsewhere, we considered this tumor to be primary in the spleen, and it was presumed that the tumor arose either from invaginated capsular mesothelium of the spleen or from heterotopic pancreatic or enteric tissue within the spleen.