Objective: To determine the frequency of subclinical hormone secretion in incidentally discovered adrenal masses.
Design: We reviewed the radiologic reports of 1779 consecutive computed tomographic scans of the chest, abdomen, and pelvis.
Setting: Regional referral medical center.
Patients: Eighty-nine patients with abnormalities of one or both adrenal glands were identified. Patients with nonadrenal gland malignant neoplasms, primary aldosteronism, adrenal hemorrhage, and death or severe illness were not investigated. The final study group consisted of 26 patients with incidentally discovered adrenal masses.
Main outcome measures: Aldosterone secretion was assessed by measuring plasma renin activity and the plasma aldosterone concentration in patients with unexplained hypokalemia. We evaluated cortisol secretion by performing a 1-mg overnight dexamethasone suppression test and by measuring the corticotropin concentration at 8 AM by a sensitive method. In patients with low corticotropin values, we also measured the 24-hour urinary excretion of free cortisol and 17-ketosteroids and assessed diurnal variation by measuring plasma cortisol concentrations at 8 AM and 4 PM. Adrenal medullary function was studied by measuring urinary free catecholamines.
Results: One patient had unrecognized primary aldosteronism, two patients had elevated free catecholamine excretion, and three patients (12%) had subclinical Cushing's syndrome.
Conclusion: Based on our observations and a review of the literature, we conclude that subclinical hormone secretion, especially cortisol secretion, is more common in patients with incidentally discovered adrenal masses than previously appreciated. Surgeons and anesthesiologists must be alert to the possibility that adrenal insufficiency or a hypertensive crisis may develop in the perioperative period in patients with incidentally discovered adrenal masses.