A benign tumor that develops in the adrenal gland and tends to run in families. The tumor may be nonfunctioning (does not produce hormones) or functioning in which case excessive levels of hormones can cause a variety of symptoms depending on which hormone is involved. Adrenal hormones made in the cortex (outer part of the gland) are aldosterone, corticosteroids and androgenic steroids . Adrenalin and noradrenalin are the hormones made in the medulla (central part of the adrenal gland). See also Adrenal adenoma, familial