AbstractThe widespread use of imaging modalities may detect clinically unsuspected “pancreatic cysts” in which the differential diagnoses include pseudocysts, cystic neoplasms, necrotic carcinomas, abscesses, and, uncommonly, islet cell tumors. Accurate preoperative diagnosis requires clinical, radiologic, microbiologic, cytologic, and biochemical studies. Material obtained by fine‐needle aspiration from cysts can be triaged for cytology, amylase, and carcinoembryonic antigen (CEA) studies. The four cases described suggest that an elevated fluid CEA is specific for carcinoma, and an elevated amylase and negative CEA suggests pseudocysts, while both amylase and CEA are negative in abscesses. Thus, “cystic lesions of pancreas” can be accurately diagnosed in cases in which radiologic and cytologic studies are inconclusive. The routine inclusion of these tests with cytologic study should be encouraged to obviate unnecessary surgery for diagnostic purposes. Diagn Cytopathol 198