Myelolipomatous adrenal masses causing Cushing's syndrome.

Adrenal myelolipomas are uncommon benign tumors, composed of mature adipose tissue and haematopoietic elements in varying proportions. They are usually asymptomatic, non-functioning adrenal incidentalomas, but there have been a few reports of myelolipomatous masses associated with adrenocortical hypersecretion. We report two cases of large mixed adrenal tumors, with heterogeneous appearance and areas of fat density in imaging techniques, and with autonomous cortisol production leading to Cushing's syndrome. Both underwent adrenalectomy and the histological study showed an adrenocortical adenoma with widespread myelolipomatous metaplasia. Hypercortisolism resolved in the one patient that could be evaluated after surgery. We review all the previous reported cases of hypercortisolism associated with adrenal myelolipomas. We also discuss the recommended diagnostic approach and therapeutic management of adrenal masses of lipomatous appearance.