Adrenal Incidentalomas: An Approach to Uncertainty

Adrenal incidentaloma is defined as an adrenal mass 1 cm or more in diameter that is discovered serendipitously by radiologic examination, in the absence of symptoms or clinical findings suggestive of adrenal disease. As imaging techniques have improved and computed imaging has become accepted practice in medicine, the identification of adrenal incidentalomas has become more frequent. William F. Young, Jr, MD, of the Division of Endocrinology, Diabetes, Metabolism, and Nutrition at Mayo Clinic in Rochester, says: “Adrenal incidentalomas are not new. Instead of finding them at autopsy, we are now finding them during life with computed imaging. There is an age-dependent occurrence of adrenal cortical adenomas found at autopsy. Thus, the probability of finding an unsuspected adrenal adenoma on computed abdominal imaging in a 20to 29-yearold person is approximately 0.2%, compared with 7% in a person older than 70 years.” The majority of adrenal incidentalomas are clinically nonhypersecretory benign adrenal cortical adenomas. However, more than 45 different diagnoses have been reported in patients with incidentally discovered adrenal masses (Table on page 2). An adrenal incidentaloma should be characterized with respect to both functional status, with a medical history, physical examination, and hormonal assessment, and malignant potential, with an assessment of the imaging phenotype and mass size.