RESPONSE OF THE PLASMA 17-HYDR0XYC0RTIC0-STEROID LEVEL TO GEL-ACTH IN TUMOROUS AND NON-TUMOROUS CUSHING'S SYNDROME

Abstract
INTRODUCTION AKNOWLEDGE of the underlying adrenocortical pathology is of practical importance in the therapeutic management of Cushing's syndrome. There are no clinical signs or symptoms which serve to differentiate Cushing's syndrome due to adrenocortical carcinoma from that due to adenoma or hyperplasia. Differentiation of the adrenal pathology by means of the level of urinary neutral 17-ketosteroids is often impossible, although a very high titer of ketosteroids is suggestive evidence in favor of a malignant adrenocortical lesion (1). Plasma and urinary 17-hydroxycorticoid assays and x-ray examination following retrorectal oxygen insufflation may prove to be indecisive in distinguishing tumorous from nontumorous Cushing's syndrome (1). More recently, the use of stimulation of the adrenal cortices with corticotropin (ACTH) has been attempted in Cushing's syndrome in an effort to distinguish tumor from hyperplasia (2–4). The few reports in the literature to date concerning the diagnostic usefulness of this method have been encouraging. The changes in the plasma 17-hydroxycorticoid level following the intramuscular administration of Gel-ACTH in 8 cases of classic Cushing's syndrome (including 3 each with hyperplasia and malignant tumor and 2 with adenoma) are reported here. All patients were explored surgically.