GENERAL MEASURES
. Discontinue offending medications, if any
. Treat underlying causes.
. Symptom management
. Galactorrhea causing patient anxiety
. Fertility restoration
. Pituitary adenoma
. Prevention of osteoporosis
. Watchful waiting is appropriate but pituitary macroadenomas (tumors >10 mm) warrant treatment even if
asymptomatic.
. Radiation therapy is usually limited to patients not responding satisfactorily to medical or surgical therapy or sometimes given after surgery to prevent recurrence. The risk is pituitary insufficiency. Long term follow up is
needed.
Medical Care
Direct treatment is geared toward resolving hyperprolactinemic symptoms or reducing tumor size. Patients on medications causing hyperprolactinemia should have them withdrawn if possible. Patients with hypothyroidism should be given thyroid hormone replacement therapy.
" When symptoms are present, medical therapy is the treatment of choice. Patients with hyperprolactinemia and no symptoms (idiopathic or microprolactinoma) can be monitored without treatment. Consider treatment for women with amenorrhea. In addition, duel-energy x-ray absorptiometry (DEXA) scanning should be considered to evaluate bone density.
"
" The persistent hypogonadism associated with hyperprolactinemia can lead to osteoporosis. Treatment significantly improves the patient's quality of life. If the goal is to treat hypogonadism only, patients with idiopathic hyperprolactinemia or microadenoma can be treated with estrogen replacement and prolactin levels can be monitored.
"
" Radiation treatment is another option. However, the risk of hypopituitarism makes this a poor choice. It may be necessary for rapidly growing tumors, but its benefits in routine treatment have not been shown to outweigh the risks.
"
" Medication
"
o The dopamine agonist, bromocriptine mesylate, is the initial drug of choice. It lowers the prolactin level in 70-100% of patients. Agents other than bromocriptine have been used (eg, cabergoline, quinagolide). Cabergoline and pergolide are available in the United States. Cabergoline, in particular, probably is more effective and causes fewer adverse effects than bromocriptine. However, it is much more expensive. Cabergoline often is used in patients who cannot tolerate the adverse effects of bromocriptine or in those who do not respond to bromocriptine. Pergolide has not been approved by the US Food and Drug Administration (FDA) for use in patients with this condition.
o Response to therapy should be monitored by checking fasting serum prolactin levels and checking tumor size with MRI. Most women (approximately 90%) regain cyclic menstruation and achieve resolution of galactorrhea. Testosterone levels in men increase but may remain below normal.
o Therapy should be continued for approximately 12-24 months (depending on the degree of symptoms or tumor size) and then withdrawn if prolactin levels have returned to the normal range. After withdrawal, approximately one sixth of patients maintain normal prolactin levels.
o Bromocriptine also is used to shrink macroadenomas. Normalization of visual fields is observed in as many as 90% of patients. A failure to improve within 1-3 months is an indication for surgery. Tumors usually shrink to 50% of their original size in approximately 90% of patients treated for macroadenomas for 1 year. In patients with nonprolactinoma tumors (masses that are compressing the pituitary stalk), medical treatment reduces serum prolactin levels but does not reduce tumor size. Cabergoline is somewhat more effective than bromocriptine in terms of tumor shrinkage.
Surgical Care
General indications for pituitary surgery include patient drug intolerance, tumors resistant to medical therapy, patients who have persistent visual-field defects in spite of medical treatment, and patients with large cystic or hemorrhagic tumors.
DRUG TREATMENT :
1. DOPAMINE AGONISTS :
- BROMOCRIPTINE (Parlodel): Start with low dose of 1.25 mg or 2.5 mg daily, then increase as tolerated over
several weeks to 2.5 mg tid. Doses up to 30 mg daily are occasionally required for prolactinoma regression,
after which lower doses can be used for maintenance. First dose should be taken with evening meal.
- CABERGOLINE
- QUINAGOLINE
ALTERNATIVE DRUGS
. Intravaginal bromocriptine
. Sustained release bromocriptine (Parlodel SRO)
. Intramuscular bromocriptine (Parlodel LAR)
. New dopamine agonists:
. Quinagolide - administered daily
. Pergolide (Permax) - 0.05 mg QD
. Cabergoline (Dostinex) - 0.25 mg twice weekly; may increase monthly as needed up to 1.0 mg twice weekly
PATIENT MONITORING
. Depends on etiology. Consider:
. Prolactin level every 6 to 12 months.
. Formal visual fi eld testing yearly.
. MRI in one year and then every 2 to 5 years, depending on clinical course.
POSSIBLE COMPLICATIONS
. Depends on underlying cause.
. If pituitary adenoma, risk of permanent visual field loss.
EXPECTED COURSE/PROGNOSIS
. Depends on underlying cause.
. Tends to recur after discontinuation of medical therapy.
. Microadenomas sometimes regress without intervention.