Ciliated enteric duplication cyst presenting as a pancreatic cystic neoplasm: report of a case with cyst fluid analysis.

Pancreatic cysts include inflammatory pseudocysts, cystic tumors (serous and mucinous), and various rare cystic lesions. We report a case of a ciliated enteric duplication cyst that presented on computed tomographic scan as a pancreatic cystic neoplasm. Cyst fluid analysis revealed markedly increased concentrations of carcinoembryonic antigen and CA 125 and increased fluid viscosity. These features are typical for a mucinous cystic neoplasm of the pancreas and demonstrate a potential pitfall associated with the diagnosis of pancreatic cysts by chemical analyses. Enteric duplications involving the pancreas are rare, usually of gastric origin, and usually communicate with their enteric source. Morphological and histochemical analysis suggest that this cyst was of caudal foregut origin. This is the first reported case of a ciliated foregut cyst involving the pancreas. The chemical characteristics of the cyst fluid of these lesions have not been described previously.