CILIATED HEPATIC FOREGUT CYST MIMICKING NEOPLASM

We describe a ciliated hepatic foregut cyst that was clinically consid ered neoplastic because it was large, bilocular, and associated with a high serological level of carbohydrate antigen 19-9 (CA 19-9), Histol ogically, the wall of the cyst showed characteristic pseudopapillae li ned by ciliated stratified columnar epithelium with interspersed goble t cells and underlying smooth muscle. The epithelium was strongly immu noreactive for CA 19-9, We therefore conclude that large size, multilo cularity, and elevated CA 19-9 do not exclude ciliated hepatic foregut cysts from diagnostic consideration. (C) 1998 by Am. Coll. of Gastroe nterology.