SMALL NONFUNCTIONING ENDOCRINE TUMOR OF PANCREAS - COMPARISON WITH SOLID CYSTIC TUMOR

A small non-functioning islet-cell tumor of the pancreas in a 79-year- old man is reported. Ultrasonography showed a solid small mass in the body of the pancreas. All laboratory data, including serum hormones an d tumor markers, were within normal limits. A distal pancreatectomy wa s performed. Cut sections of the specimen revealed a small, hard, soli d mass measuring 2.8 x 2.2 x 2.0 cm. Histologically, the tumor consist ed of large acidophilic cells with round nuclei, and these cells were similar to those normally found in solid and cystic tumors (SCT) of th e pancreas. However, the tumor cells were slightly positive for somato statin and neuron-specific enolase. Ultrastructural studies revealed c lear nuclei with no zymogen but immature neurosecretory granules in th e cytoplasm of the tumor cells. These findings were consistent with th ose of non-functioning islet-cell tumors. We describe the clinical and histological differences between nonfunctioning islet-cell tumors and SCT based on an analysis of the literature.