What is a pituitary tumor?
A pituitary tumor is an abnormal growth of cells in the pituitary gland, which is the main hormone-producing gland in the body. About the size of a pea, the pituitary gland is located in the center of the brain behind the nose and eyes. Hormones are chemical substances the body produces that control and regulate certain cells or organs.
A tumor in the pituitary gland can disrupt the normal balance of hormones in the body. This may cause a person to become sick.
About 10% of all primary brain tumors are pituitary tumors. Only a very small number of pituitary tumors are malignant (cancerous). However, because of the location of the pituitary gland, at the base of the skull, a pituitary tumor grows upward. Eventually, some pituitary tumors will press against the optic nerves, causing vision problems.
Many pituitary tumors are small, do not cause health problems and may never need treatment. Almost all pituitary tumors can be treated, usually through medications and surgery. Most pituitary tumors can be cured.
Causes of and risk factors for pituitary tumors:
There is no obvious cause of pituitary tumors. Some pituitary tumors might be caused by stimulation from the hypothalamus — a part of the brain that signals the pituitary gland to make hormones.
People who have the rare inherited conditions such as multiple endocrine neoplasia type 1 (MEN-1) — a disorder that causes tumors in the endocrine glands (which secrete hormones into the bloodstream and include the pituitary gland) and the first part of the small intestine — or Carney complex — a disorder that causes several types of tumors, including in the pituitary gland — have a higher risk of pituitary tumors. About 1-5% of pituitary tumors occur within families.
More information about pituitary tumors:
Learn more about the diagnosis of pituitary tumors.
Learn about treatment of pituitary tumors at the Johns Hopkins Pituitary Tumor Center.