Small ACTH-secreting tumors may remain undetected on anatomic imaging (pituitary MRI, and neck and trunk CT and MRI), despite clinical and biochemical evidence of ACTH-dependent Cushing's syndrome, and noninvasive dynamic tests are not always able to distinguish between Cushing's disease and EAS due to NETs. Here, POMC is linked to Cushing syndrome due to macronodular adrenal hyperplasia.