USMLE Forum Archives - USMLE Step 3 - PROLACTINOMA
PROLACTINOMA
meduploader - 06-29-09 15:11
The most common type of pituitary tumor. The majority of lesions are microadenomas (< 1 cm).
Women: Galactorrhea; amenorrhea; oligomenorrhea with anovulation
and infertility in 90%.
Women typically present with prolactinomas earlier than men because of amenorrhea and galactorrhea. Therefore, women often have microprolactinomas (< 1 cm) at diagnosis, whereas men have macroprolactinomas.
When a woman presents with amenorrhea, hyperprolactinemia, and a homogeneously enlarged pituitary gland (up to two times normal), the first thing to rule out is pregnancy!
Men: Impotence, ↓ libido, galactorrhea (very rare).
Both: Symptoms due to a large tumor—headache, visual field cuts, and hypopituitarism.
DIFFERENTIAL
The differential includes the following
Medications.
Pregnancy, lactation: Prolactin can reach 200 ng/mL in the second trimester.
Hypothalamic lesions; pituitary stalk compression or damage.
Hypothyroidism: TRH stimulates prolactin secretion.
Nontumoral hyperprolactinemia (idiopathic).
DIAGNOSIS
Labs: Elevated prolactin with normal TFTs and a -- ive pregnancy test.
Imaging: Obtain an MRI if prolactin is elevated in the absence of pregnancy or the medications
TREATMENT
Medical: Dopamine agonists such as bromocriptine or cabergoline. Once prolactin is normalized, repeat pituitary MRI to ensure tumor shrinkage.
Cabergoline has fewer side effects.
Bromocriptine is preferred for ovulation induction, since there is more experience with it in pregnancy.
Dopamine agonists (especially cabergoline at high doses) have been associated with cardiac valve abnormalities.
Surgery: Transsphenoidal resection is curative in 85–90% of patients and is generally used if medical therapy is ineffective or if vision is threatened.
Radiation: Conventional radiotherapy or gamma-knife radiosurgery if the tumor is refractory to medical and surgical therapy.
meduploader - 06-29-09 15:11
The most common type of pituitary tumor. The majority of lesions are microadenomas (< 1 cm).
Women: Galactorrhea; amenorrhea; oligomenorrhea with anovulation
and infertility in 90%.
Women typically present with prolactinomas earlier than men because of amenorrhea and galactorrhea. Therefore, women often have microprolactinomas (< 1 cm) at diagnosis, whereas men have macroprolactinomas.
When a woman presents with amenorrhea, hyperprolactinemia, and a homogeneously enlarged pituitary gland (up to two times normal), the first thing to rule out is pregnancy!
Men: Impotence, ↓ libido, galactorrhea (very rare).
Both: Symptoms due to a large tumor—headache, visual field cuts, and hypopituitarism.
DIFFERENTIAL
The differential includes the following
Medications.
Pregnancy, lactation: Prolactin can reach 200 ng/mL in the second trimester.
Hypothalamic lesions; pituitary stalk compression or damage.
Hypothyroidism: TRH stimulates prolactin secretion.
Nontumoral hyperprolactinemia (idiopathic).
DIAGNOSIS
Labs: Elevated prolactin with normal TFTs and a -- ive pregnancy test.
Imaging: Obtain an MRI if prolactin is elevated in the absence of pregnancy or the medications
TREATMENT
Medical: Dopamine agonists such as bromocriptine or cabergoline. Once prolactin is normalized, repeat pituitary MRI to ensure tumor shrinkage.
Cabergoline has fewer side effects.
Bromocriptine is preferred for ovulation induction, since there is more experience with it in pregnancy.
Dopamine agonists (especially cabergoline at high doses) have been associated with cardiac valve abnormalities.
Surgery: Transsphenoidal resection is curative in 85–90% of patients and is generally used if medical therapy is ineffective or if vision is threatened.
Radiation: Conventional radiotherapy or gamma-knife radiosurgery if the tumor is refractory to medical and surgical therapy.
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Re: PROLACTINOMA mtniharika - 09-11-09 16:01 Hyperprolactinemia can cause reduced estrogen production in women and reduced testosterone production in men.Although estrogen/testosterone production may be restored after treatment for hyperprolactinemia, even a year or two without estrogen/testosterone can compromise bone strength, and patients should protect themselves from osteoporosis by increasing exercise and calcium intake through diet or supplementation, and by avoiding smoking. Patients may want to have bone density measurements to assess the effect of estrogen/testosterone deficiency on bone density. testosterone/estrogen replacement therapy may be added.
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