Pancreatic somatostatinoma.

The presence of cholelithiasis, steatorrhea, diabetes mellitus, and a pancreatic tumor initiated a diagnostic workup for somatostatinoma in a 43 year old black woman. The hypothesis of somatostatinoma was supported by a high level of plasma-like immunoreactivity and secretory granules resembling D-cell granules by electron microscopy. The patient has been euglycemic and well since complete resection of the tumor. This is the seventh reported case of somatostatinoma and the second to be benign.