Pheochromocytoma combined with pre-clinical Cushing's syndrome in the same adrenal gland

Pheochromocytoma (PHEO) occasionally associates with pathological lesions of the adrenal cortex. In most of them, ectopic adrenocorticotropic hormone (ACTH) produced by PHEO resulted in bilateral adrenocortical hyperplasia. The coexistence of PHEO and pre-clinical Cushing's syndrome (PCS) of the same adrenal gland has rarely been reported. We report on a patient and discuss the peculiar diagnostic aspects of this entity. A 52-yr-old Turkish woman was hospitalized at Farabi Hospital for further examinations of a right adrenal mass that was incidentally discovered by abdominal ultrasonography during examinations for abdominal bloating and "gas" in other hospital. The patient had a history of palpitations, nervousness, sweating and heat intolerance. On admission, her blood pressure was 140/90 mmHg. A physical examination revealed no signs of an excessive production of adrenocortical steroids such as in CS. Tension Holter monitoring revealed paroximal hypertension attacks (183/105 mmHg). Urinary catecholamines were markedly increased. Her serum cortisol concentrations ranged from 5 to 17 microg/dl, whereas ACTH levels were undetectable. Cortisol was not suppressed on the overnight 1 mg oral dexamethasone suppression test (DST), 2-day low-dose dexamethasone suppression test (DST). Abdominal computed tomography and magnetic resonance imaging studies revealed a solid round tumor approximately 4 cm in diameter, located in the right adrenal gland. A 131 lodine-metaiodobenzylguanidine (131 I-MIBG) scan revealed uptake within tumor in the right adrenal gland. Right adrenalectomy was performed; the surgical specimen revealed PHEO and adrenocortical hyperplasia. To our knowledge, the present report is a rare case of PHEO combined with PCS in the same adrenal gland.