Adrenal rest carcinoma in hilum of kidney.

Adrenocortical rests are uncommon in adults and infrequently undergo malignant changes. Most of the published cases are those of functional tumors allowing preoperative diagnosis on the basis of the resulting endocrinopathy. Most nonfunctioning tumors were found accidentally at operation or autopsy. A case is presented of a parapelvic nonfunctioning adrenocortical rest carcinoma situated in the renal hilus in a fifty-year-old woman. No such tumor has been described previously.