FINE-NEEDLE ASPIRATION CYTOLOGY OF IDIOPATHIC PANCREATIC-ISLET CELL ADENOSIS

A 68-yr-old woman was hospitalized because of abdominal pain, an enlar ged pancreatic head by CT and a questionable 4-cm mass in the liver. F ine-needle aspiration (FNA) of the pancreatic head disclosed a highly cellular specimen consisting of clusters of cytologically bland, monot onous, small nuclei and variable but generally sparse cytoplasm. Becau se of the differentiated monomorphic character of the cell clusters, t he postaspiration differential cytopathologic diagnosis included islet cell tumor, acinic cell tumor, carcinoid, lymphoma, and well differen tiated ductal adenocarcinoma. Pancreaticoduodenectomy and hepatic biop sy yielded a grossly normal pancreas and a cirrhotic liver. Histologic examination of the pancreas revealed a spotty but extensive spectrum of islet changes ranging from normal to bland hyperplasia, nesidioblas tosis, microadenosis, and neuroendocrine microadenomas, all appearing in a light and electron microscopic context of an otherwise normal pan creas. This case highlights the differential diagnostic ambiguities pr esented by a continuum of pancreatic islet cell proliferations, especi ally among patients in whom there are no known predisposing factors fo r such diffuse preneoplastic or neoplastic changes. (C) 1993 Wiley-Lis s, Inc.