Clinical Investigation of Adrenal Incidentalomas in Japanese Patients of the Fukuoka Region with Updated Diagnostic Criteria for Sub-clinical Cushing's Syndrome

Objectives We retrospectively investigated the clinical and endocrinological characteristics of adrenal incidentalomas. Methods We studied 61 patients who had been diagnosed with adrenal incidentalomas and had undergone detailed clinical and endocrinological evaluations while hospitalized. We used common criteria to diagnose the functional tumors, but for sub-clinical Cushing's syndrome, we used an updated set of diagnosis criteria: serum cortisol ≥1.8 μg/dL after a positive response to a 1-mg dexamethasone suppression test if the patient has a low morning adrenocorticotropic hormone (ACTH) level (