Epithelial cyst of the spleen with squamous metaplasia: a rare entity

A case of ruptured splenic cyst with elevated serum levels of CEA treated by laparoscopic unroofing

Splenic cysts are rare and tend to have elevated tumor markers, of which carbohydrate antigen (CA) 19-9 is the most frequently elevated. Therefore, splenic cysts with elevated serum carcinoembryonic antigen (CEA) levels and without CA19-9 elevation are extremely rare. A 26-year-old woman presented with sudden upper abdominal pain while sleeping. Contrast-enhanced computed tomography (CT) showed an 85-mm simple splenic cyst in the upper pole and a moderate amount of ascites around the spleen. The serum levels of CEA, but not CA19-9, were elevated. Spontaneous rupture of a splenic cyst was diagnosed. We performed elective laparoscopic unroofing. The histological findings revealed a stratified squamous epithelium on the inner surface of the cystic wall. On immunohistochemical examination, the squamous epithelium was found to be positive for cytokeratin (CK)7, negative for calretinin, and positive for CEA. The histological diagnosis was an epidermoid cyst. Three months after the operation, the elevated serum tumor marker levels of CEA were normalized. Splenic cysts with high levels of CEA and low levels of CA19-9 are extremely rare. Laparoscopic unroofing is a useful operative procedure for ruptured splenic cysts with elevated levels of serum tumor markers.