Multiple endocrine neoplasia type I with Cushing's disease, primary hyperparathyroidism, and insulin-glucagonoma

A case of multiple endocrine neoplasia type I (MEN I) consisting of Cushing's disease, primary hyperparathyroidism, and insulin-glucagonoma is described. This condition was treated successfully by transsphenoidal pituitary adenomectomy, subtotal parathyroidectomy, and enucleation of pancreatic tumors. Histologic features showed a basophilic adenoma in the pituitary, chief cell hyperplasia in the parathyroid, and islet cell adenomas in the pancreas. The rarity of multiple endocrine hyperfunctioning states and the pathophysiology created by the combination of these three diseases in this patient are of interest.