endocrine and metabolic disorders
Prolactinoma
Treatment of Prolactinoma
Depends on sex, cause, symptoms, and other factors When indicated, initial treatment is usually with adopamineagonist Microprolactinomascan be treated in multiple ways. Asymptomatic patients who have prolactin levels<100 mcg/L (4,348 pmol/L) and normal CT or MRI results or who have only microadenomas can probably be observed; serum prolactin often normalizes within years. Patients with hyperprolactinemia should be monitored with quarterly measurement of prolactin levels and undergo sellar MRI or CT annually for at least an additional 2 years. The frequency of sellar imaging can then be reduced if prolactin levels do not increase. In women,indications for treatment include Desire for pregnancy Amenorrhea or significant oligomenorrhea (because of the risk of Osteoporosis ) Hirsutism Low libido Troublesome galactorrhea In men,galactorrhea itself is rarely troublesome enough to require treatment; indications for treatment include Hypogonadism (because of the risk of osteoporosis) Erectile dysfunction Low libido Troublesome infertility The initial treatment for both sexes is usually adopamineagonist such asbromocriptine1.25 to 5 mg orally twice a day or the longer-actingcabergoline0.25 to 1.0 mg orally once or twice a week, which lower prolactin levels.Cabergolineis the treatment of choice because it is more easily tolerated (has a lower frequency of adverse effects) and more potent thanbromocriptine. Women trying to become pregnant should stopcabergolineorbromocriptineuse at the time of a positive pregnancy test result. Quinagolide, a nonergot-deriveddopamineagonist, is also an option for hyperprolactinemia. It is started at 25 mcg orally once a day and titrated over 7 days up to the usual maintenance dose of 75 mcg once a day (can increase weekly in 75- to 150-mcg increments to maximum dose 600 mcg once a day). Quinagolide should not be used by women contemplating pregnancy. Patients with concomitant hypogonadism who elect to not usedopamineagonist therapy can be treated with estrogen (with or without aprogestin, as indicated) ortestosterone. Women with a microadenoma who are clinically hypoestrogenic or have lowestradiollevels, can be given exogenousestrogen. Exogenousestrogenis unlikely to cause tumor expansion. Patients withmacroadenomasgenerally should be treated initially withdopamineagonists even in cases of large tumors invading and compressing the optic chiasm.Dopamineagonists usually shrink a prolactin-secreting tumor.Dopamineagonists will not shrink a nonfunctioning tumor that is causing pituitary stalk compression, although prolactin levels will decrease. If prolactin levels fall and symptoms and signs of compression by the tumor abate, no other therapy may be necessary. However, typically, larger, nonfunctioning lesions need additional treatment, usually surgery. Althoughdopamineagonist treatment usually needs to be continued long-term, prolactin-secreting tumors sometimes remit, either spontaneously or perhaps aided by the drug therapy. Sometimes, therefore,dopamineagonists can be stopped without a recurrence of the tumor or a rise in prolactin levels; remission is more likely with microadenomas than macroadenomas. Remission is also more likely after pregnancy. and pergolide, are thought to have caused valvular heart disease in some patients with Parkinson Disease . Studies evaluating the lower doses of Surgery is second-line therapy in patients whose tumor is resistant todopamineagonists or in patients who are intolerant of medical therapy. Radiation therapy should be used only in patients with progressive disease who do not respond to other forms of therapy. With irradiation, hypopituitarism often develops several years after therapy. Monitoring endocrine function and sellar imaging are indicated yearly for life. agonist therapy probably should be re-started. The Endocrine Society guidelines ( Treatment reference ) recommend using 1.Melmed S, Casanueva FF, Hoffman AR, et al: Diagnosis and Treatment of Hyperprolactinemia: An Endocrine Society Clinical Practice Guideline.J Clin Endocrinol Metab96(2): 273–288, 2011. 