Prolactinoma is tumor of pituitary gland located in the brain. It arises due to the growth of cells which secrete prolactin.
It is the most common pituitary tumor (nearly 50%) .
In which age group it is commonly seen?
It usually appears in women aged 20–50 years. However it can occur in children also. It is more common in female but even male get afffected with a female:male ratio of 10:1 in that period.
How do we classify these tumors?
We classify them as microprolactinoma and macroprolactinoma. Microprolactinomas are less than one cm in diameter while macroprolactinomas are more than one cm in diameter. More than 90% of prolactinomas are microprolactinomas , whereas the rest are macroprolactinomas.
What are the symptoms of prolactinoma?
Symptoms varies according to the age, gender. In children it may present with headache, vision problems, growth disturbances. In female it will present in the form of menstrual irregularities, breast secretion,headache, vision problems, infertility. In male it will present with headache, vision prblem, hypogonadism, erctile dysfunction.
What is the treatment for it?
These tumors are generally treated with medicines called Dopamine agonists like cabergoline and bromocriptine. Cabergoline is being preferred to bromocriptine, because of its better tolerance and feasibility of administration.
Other modality of treatment include- surgery, radiation therapy.
Resistance or intolerance to dopamine agonists are the main indications for transsphenoidal adenomectomy in patients with macroprolactinoma.
External radiation therapy has been used in patients with poor response to medical and surgical procedures.
What is the duration of treatment in case of prolactinoma?
Generally these patients require long term treatment. In patients with microprolactinoma treatment can be stopped after prolactin is normal and MRI is not showing any mass.
Is complete cure possible in case of macroprolactinoma?
Complete remission (normal prolactin levels associated with absence of tumor image) is not easy to achieve.
In 10 yrs follow up by Kars and team in Netherland 85% patients were able to achieve control of prolactin levels with medicine but in only 22% patients prolactin level were normal after stopping medicines. Tumor shrinkage was evident on MRI in 57% of the patients. Surgery was needed in 35% patients.(Ref- Kars M, Pereira AM, Smit JW, Romijn JA. Long-term outcome of patients with macroprolactinomas initially
treated with dopamine agonists. Eur J Intern Med. 2009 Jul;20(4):387-93. doi:
10.1016/j.ejim.2008.11.012. Epub 2008 Dec 30. PMID: 19524180.)
In another study 31% patients have rcurrence in elevation of prolactin after stopping the medicines. (Ref- Colao A, Di Sarno A, Cappabianca P, Di Somma C, Pivonello R, Lombardi G. Withdrawal of long-term cabergoline therapy for tumoral and nontumoral hyperprolactinemia. N Engl J Med. 2003 Nov
20;349(21):2023-33. doi: 10.1056/NEJMoa022657. PMID: 14627787)
Another study showed a recurrence rate of hyperprolactinemia in 43.3% of patients with macroprolactinomas after 5 years of CAB
withdrawal. There are some studies suggesting reduction in prolactin level with long term treatment.
So to conclude majority of patients with a prolactinoma, certainly those with macroadenomas, will require therapy that typically continues for many years.
Why doctor advice you to discontinue the treatment?
According to the guidelines if a patient has normal prolactin levels after therapy with dopamine agonists for at least three years and the tumor volume is markedly reduced, a trial of tapering and discontinuation of these drugs may be initiated.
Such patients need to be carefully followed to detect recurrence of hyperprolactinemia and tumor enlargement so that treatment can be promptly resumed.
When surgery is needed in case of prolactinoma?
The main surgical treatment indications include resistance, intolerance or lack of adherence to medical treatment, cerebrospinal fistulas secondary to a reduction of tumor size after therapy with DA, neuro- ophthalmologic defects such as rapid loss of vision or cranial pars paralysis due to intratumoral hemorrhage or pituitary apoplexy.
What other things need to be checked in prolactinoma patients?
Calcium levels of the patient, prolactin of other family members. These things are need to detect some special type of prolactinoma. in addition other pitutiary hormones need to be checked in the patients.