Bilateral non-nodular enlargement of the adrenal glands in a patient with thymic carcinoid tumor compatible with acquired adrenal hyperplasia.

Thymic carcinoid tumor is the most common type of neuroendocrine tumor of the thymus. Up to 50% of affected patients have hormonal abnormalities, and up to 35% have Cushing syndrome owing to tumoral production of adrenocorticotropic hormone (ACTH). ACTH secretion causes adrenal hyperplasia in these patients.