A pituitary tumor that causes excess secretion of the hormone prolactin .
Alternative Names
Prolactinoma-females; Adenoma - secreting
Causes, incidence, and risk factors
Prolactin is a hormone that induces lactation or milk formation. The size of the prolactinoma correlates with the excess prolactin level ; the larger the tumor , the higher the level of prolactin that is secreted. Smaller tumors, called microprolactinomas are more common in women, and larger tumors, called macroprolactinomas, are more common in men. Many of the smaller tumors do not appear to progress to larger tumors. Many women first experience symptoms while on oral contraceptives or have cessation of menses when oral contraceptives are discontinued. Prolactinomas may grow during pregnancy and may be diagnosed in the postpartum period. Sexual dysfunction occurs in many men. Prolactinomas occur most commonly in those under 40 years old. The incidence is 3 out of 10,000 men and 1 out of 1,000 women.
Signs and tests
Prolactin levels Cranial MRI or cranial CT scan that shows a pituitary mass
Decreased testosterone levels in men
Treatment
The symptoms of infertility , irregular menses, decreased sexual interest , and milk flow not related to childbirth or nursing can be improved with treatment. Men should also be treated when decreased sexual drive, infertility, or impotence are present. Bromocriptine (a dopamine agonist medication) is a medication used to return prolactin levels to normal in both men and women. Larger tumors or those resistant to bromocriptine may respond to surgical resection, radiation therapy , or a combination of treatments.
Expectations (prognosis)
Long-term studies are not available for information on prognosis (probable outcome).
Complications
Tumor regrowth is the main complication. If untreated, tumor growth may result in permanent visual loss.
Calling your health care provider
Call for an appointment with your health care provider if symptoms of a prolactinoma develop. If you have had a prolactinoma in the past, call for an appointment with your health care provider if you experience recurrence of the symptoms.
Prevention
There is no known prevention.