Certain factors can make one person more likely to get a pituitary tumor than another person. These are called risk factors. In some cancers, doctors have identified risk factors that can be avoided, such as smoking or sun exposure. With pituitary tumors, doctors are not sure what exactly causes pituitary tumors and very few risk factors have been identified. Many people who get a pituitary tumor have no known risk factors.
One risk factor for a pituitary tumor is having a condition called multiple endocrine neoplasia (MEN). One type is known as MEN1. MEN1 is a hereditary condition. People with it have a high risk of getting tumors of the pituitary, the parathyroid, and the pancreas. Each child of a parent (mother or father) who has MEN1 has a 50 percent chance of getting MEN1.
Another hereditary risk factor is having multiple endocrine neoplasia, type IV (MEN4). People who have inherited this syndrome have a higher risk of pituitary tumors and certain other tumors.
Other rare inherited and noninherited genetic problems can also increase the risk of pituitary tumors. Changes in the gene AIP can also be a risk factor. AIP can be inherited from a parent or can occur during a person's lifetime. In rare cases, pituitary tumors seem to run in some families without a known genetic syndrome.
No standard screening methods are used to find pituitary tumors in people who are not at increased risk. If a person has an inherited condition such as MEN1 syndrome, he or she should discuss screening with his or her doctor. For members of a family with the MEN1 syndrome, blood testing may be recommended to look for abnormal pituitary hormone levels. These blood tests raise the chances of finding a tumor early so it can be treated.