Cushing's syndrome caused by adrenal tumor

Definition:

A metabolic disorder caused by excessive production of cortisol by a tumor of the adrenal gland.

Causes, incidence, and risk factors:

Cushing's syndrome is caused by excess glucocorticoid hormone secretion over a long period of time. Primary tumors of the adrenal glands that secrete cortisol account for 15% of the cases of Cushing's syndrome, and are frequently malignant (cancerous). Other causes are secretion of adrenocorticotrophic hormone (ACTH) by a pituitary tumor or from another organ (ectopic Cushing's syndrome), or by chronic administration of corticosteroids--drugs commonly used to treat conditions such as rheumatoid arthritis and asthma. Adrenal tumors may occur at any age, but 70% occur in adults. The frequency is higher among women. The incidence is 6 out of 1,000,000 people.