ACTH-producing pheochromocytoma.

A benign adrenal medullary tumor that secreted adrenocorticotropic hormone (ACTH) was associated with bilateral adrenocortical hyperplasia and clinically evident Cushing syndrome. The clinical and chemical features were those usually associated with pituitary Cushing disease, including partial suppression of urinary OH steroids after administration of 8 mg of dexamethasone. The fractionization of the tumor's ACTH revealed 70% little "biologically active" ACTH, which is usually found in this concentration only in pituitary tissue.