Adrenal Incidentalomas: Do All Patients Require a Biochemical Workup?

Adrenal incidentalomas are common findings on cross-sectional imaging, and most represent benign adrenocortical adenomas. The traditional approach has been to perform biochemical testing in essentially every patient to exclude pheochromocytoma, cortisol excess, and, when clinical suspicion is present, primary aldosteronism. However, this algorithmic approach may result in overinvestigation in light of improved adrenal imaging, recognition of the low prevalence of clinically important hormone excess, and concerns about false-positive testing. The 2023 European Society of Endocrinology guideline continues to recommend clinical and endocrine assessment for all patients but provides an important imaging-based nuance: in a homogeneous adrenal mass with ≤10 Hounsfield units on unenhanced computed tomography, the probability of pheochromocytoma is extremely low, and biochemical testing for metanephrines may reasonably be omitted. In contrast, testing for mild autonomous cortisol secretion remains broadly recommended because clinically silent cortisol excess is associated with metabolic syndrome and potential morbidity. This review examines the arguments for and against universal biochemical workup and proposes a risk-stratified approach for clinicians.