Tumors of the pituitary gland are generally not cancerous, and many of these abnormal growths never cause symptoms. If the tumor enlarges to the point of compressing the surrounding tissues, headaches and vision disturbances may develop. Pituitary tumors usually produce an excess of certain hormones, causing endocrine disease, according to the National Cancer Institute. Treatment options depend on the type and size of the tumor.
Medicines
If the tumor is found to be a hormone producing tumor, drugs are used to address the symptoms produced by the particular hormone. Most pituitary tumors produce the hormone prolactin and are treated with the dopaminergic agonists, bromocriptine, pergolide or cabergoline. These medications cause the tumor to shrink. They are also used to block the effects of other hormones secreted in excess by the tumor. Prolactin-producing tumors usually do not need surgical removal, says Merck Manuals Medical Library.
Some pituitary tumors make too much growth hormone. Drugs called somatostatins can decrease growth hormone production and shrink the tumor.
Pegvisomant is a drug that blocks growth hormone's effects on the body. Even though growth hormone producing tumors can be partially treated with drug therapy, surgical removal of the tumor is necessary.
Surgery
Some types of pituitary tumors are not candidates for drugs as the sole therapy and must be removed surgically. The American Cancer Society describes transphenoidal surgery as the most common surgical method. It is generally used for the removal of small tumors. This procedure involves using medical instruments inserted through the nasal passages, in order to remove the tumor. For a large or invasive tumor, it is sometimes necessary to open the bones of the skull. This known as a craniotomy and carries greater risks than transphenoidal surgery.
Radiation
There are several types of radiation therapy for treating pituitary tumors depending on the type, size, and shape of the tumor. Conventional radiation therapy involves directing the beam of radiation at the pituitary gland 5 times per week for 4 to 6 weeks. This method works very slowly, and can take years to fully control symptoms.
Proton beam radiation focuses a beam of protons precisely on the tumor. This method may be less damaging to surrounding tissue than conventional radiation treatment, but it is not in widespread use.
Another type of radiation therapy is stereotactic radiosurgery. A targeted, intense beam of radiation is focused directly on the tumor. One or more treatments can be given. The treatment might take months to achieve full benefit and is limited to use on tumors not near important nerves.
