Pre-toxic adrenocortical adenoma ("pre-Cushing syndrome"): role of 17-hydroxyprogesterone dosage under ACTH analog stimulation. Apropos of a case

We report on a case of a 63-year-old male patient who presented with an adrenal incidentaloma corresponding to a pre-toxic adrenocortical adenoma ("pre-Cushing's syndrome"). Nycthemeral cortisol cycle and free urinary cortisol were within the normal range. Basal ACTH and dehydroepiandrosterone sulfate levels were decreased and the 17-hydroxyprogesterone (17OHP) response under ACTH stimulation (tetracosactide) was increased. The ACTh test appears mandatory in the incidentaloma work-up to order to identify the pre-toxic adenomas. Its elevation reflects likely intra-tumoral enzymatic defects. Pre-Cushing's syndrome therapeutic management is still debated. No surgery was performed in our patient. A 3-year follow-up did not show overt Cushing's syndrome features.