Medical treatment is the first line therapy only for pituitary tumors producing prolactin (prolactinomas). All other tumors should be evaluated for surgical resection unless they are non-functioning (ie they don’t make any hormone) and are small enough that they do not impact pituitary function.
When surgery is contraindicated or fails to cure a growth hormone or ACTH secreting tumor, medical therapies are available but should only be managed by a team of experts as these are rare conditions in which medical management needs to be tailored to individual patients. Medical treatment is also essential for the replacement of partial or complete pituitary insufficiencies. Pharmacologic approaches to these two conditions will be discussed briefly below.
A prolactinoma is a benign tumor of the pituitary gland that produces too much of a normal hormone, prolactin. Prolactinomas should be treated when they cause bothersome milk production, hypogonadism (low reproductive hormones, infertility and lack of periods in women, and low testosterone and impotence in med) or are larger than a centimeter.
Most prolactinomas can be successfully treated medically, with either cabergoline (Dostinex®) or bromocriptine (Parlodel®). These drugs often reduce the size of the tumor and at the same time decrease the abnormally high level of prolactin in the blood very rapidly. Cabergoline or bromocriptine may control the tumor and bring the levels of prolactin in the blood back to normal, and they can make the tumor disappear especially if the tumor is very small. Treatment with these drugs may be continued for many years or indefinitely, but if the prolactin becomes normal or the tumor disappear these treatments can be discontinued with evidence of cure in about half of the patients treated.
In some cases, when patients have side effects from the medications, have other medical conditions that make it dangerous or difficult to take the medications, or have other reasons for not taking the medications, surgery is a safe and effective option. However, unless there are very good reasons to avoid medical treatment, we almost always recommend medical treatment as the first line for dealing with a prolactinoma.