Hyperprolactinemia can usually be controlled. Minimal elevations
usually do not need any treatment. The overwhelming majority of
patients with significant excess in circulating prolactin concentrations
can be effectively treated with medication alone (often Bromocriptine).
Surgical excision of pituitary prolactinomas (tumors of lactotrophs,
the prolactin producing cells of the pituitary gland) is currently
reserved for large symptomatic tumors, patients noncompliant with
medical treatment (the use of medication for treatment) or for
tumors that have failed to respond to medical management. When
surgery is recommended, it is usually performed as a "transsphenoidal
microsurgical resection" (with a small incision made under
the upper lip) which has minimal cosmetic consequences and fewer
major complications than a craniotomy (opening of the skull).
Treatment depends on the fertility goals of the couple, the reason
for the excess prolactin, and the woman's symptoms.
If
pregnancy is not desired,
the radiologic exam demonstrates either no tumor or a microadenoma
(prolactinoma less than 1 cm diameter),
there is either no galactorrhea or the presence of milk is not
bothersome to the patient, and
the patient does not have a low circulating estrogen concentration
then she can reasonably consider "no active treatment."
That is, she can consider continuing without medication, have
her blood levels of prolactin checked 1-2 times a year for a few
years, and recheck the radiologic exam every 1-2 years for a few
years to confirm that a tumor is not rapidly growing.
If
pregnancy is not desired but
the patient has bothersome galactorrhea
then this is usually effectively treated by normalizing the prolactin
concentrations with medication. There are women who will continue
to experience galactorrhea with normal prolactin concentrations,
but the mechanism for this is not usually clear. Most likely the
galactorrhea is due to the "most bioactive forms of prolactin"
comprising a greater than normal percentage of the total amount
of immunoreactive prolactin (the amount detected in the assays).
Also, this may be due to an increase in breast cell receptors
for prolactin.
If
pregnancy is not desired but
the patient has a low circulating estrogen concentration
then the treatment for the low estrogen should be provided. Medical
management of the excess prolactin to bring it into the normal
range will generally correct the estrogen abnormality. If medical
management of the excess prolactin is not desired, then estrogen
replacement should be strongly recommended (if not otherwise contraindicated)
to protect the woman from the harmful effects associated with
a lack of estrogen (such as osteoporosis and heart disease). Birth
control pills or traditional hormone replacement medication (such
as Premarin and Provera) can be given.
If
pregnancy is desired,
then an attempt to correct the ovulatory dysfunction associated
with excess prolactin concentrations should be initiated. Usually
medication to reduce the prolactin concentrations is most effective
and all that is required. Prolactin secretion from the pituitary
gland is inhibited by dopamine and medications that act similar
to dopamine (dopamine agonists). The response to the medication
usually results in improvement of ovulation within 1-2 months
of normalization of prolactin.
If
a woman becomes pregnant while taking medication for excess prolactin
(such as Bromocriptine),
then the physician usually discontinues the medicine during the
pregnancy. One exception can be when there is a history of a large
symptomatic tumor (macroadenoma). Prolactin levels generally increase
and tumor growth may occur in high estrogen states (like pregnancy).
In the early 1980s, a metaanalysis of the available literature
reported that of 275 women with pituitary prolactinomas, 215 women
had microadenomas and less than 1% of these had either visual
changes or radiologic evidence of tumor growth during pregnancy
(5% did have headaches), and 60 women had macroadenomas with 20%
of these having visual changes or radiologic evidence of growth.
Therefore, the need for treatment in pregnancy is uncommon.
Prolactin is the hormone primarily responsible for breast milk
production during pregnancy and lactation, with circulating levels
of prolactin typically increasing up to 10 fold greater than the
nonpregnant levels by the end of pregnancy.
The size of a prolactinoma generally decreases with medical treatment.
In microadenomas, reports demonstrate that 75% of patients treated
with medication have a reduction in size and 40% have complete
disappearance of the tumor. In macroadenomas, reports demonstrate
that up to 90% have a reduction in size and most of these also
have rapid relief of any symptoms (such as vision abnormalities).
The length of therapy with medication for excess prolactin is
classically long term. There is a high incidence of recurrence
after discontinuing medication for a macroadenoma so long term
treatment is usually recommended. Women with a microadenoma can
have continued normalization of prolactin after discontinuing
the medication (about 10% if treated for 1 year and up to 20%
if treated for 2 years) so that these women may try discontinuing
the medicine to see whether they need it after 1-2 years.
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