Bilateral pheochromocytoma and islet cell adenoma of the pancreas.

An 18-year-old woman with bilateral pheochromocytomas and an asymptomatic islet cell adenoma of the pancreas represents the 11th patient to be described with this combination of endocrine tumors. No other components of any multiple endocrine adenomatosis (MEA) syndromes were present. Because of this "overlap syndrome," in which tumors that have traditionally been considered to be components of separate and mutually exclusive MEA syndromes have occurred concomitantly in the same patient, a question is raised regarding the validity of a rigid classification of these various MEA syndromes. The possibility of a pancreatic tumor should be kept in mind in any patient with a pheochromocytoma, especially if it is bilateral of multicentric in origin.