THE most frequent disturbance in carbohydrate metabolism observed in cases of corticoadrenal tumor is a diminished tolerance to glucose, with hyperglycemia. It is therefore interesting to record a case of corticoadrenal tumor in which typical hypoglycemic crises occurred repeatedly, without any other sign of Addison's disease. The clinical diagnosis was hyperinsulinism, thought to be caused by a pancreatic new growth, but the large tumor removed at operation was revealed by the pathologic examination to be a corticoadrenal tumor of embryonic type. The thyroid, the liver and the spleen were enlarged, and bilateral gynecomastia was present. A preliminary report of this case was published in December 1947 (1). Later Broster and Patterson (2) reported a case of corticoadrenal tumor in a young female with intense virilization and hypoglycemic crises; but no mention is made of enlargement of the thyroid, liver and spleen.