Pituitary tumors are abnormal growths that develop in your pituitary gland. Some pituitary tumors result in too many of the hormones that regulate important functions of your body. Some pituitary tumors can cause your pituitary gland to produce lower levels of hormones.
Most pituitary tumors are noncancerous (benign) growths (adenomas). Adenomas remain in your pituitary gland or surrounding tissues and don’t spread to other parts of your body. They can, however, push upwards into the nerves of the eyes.
There are various options for treating pituitary tumors, including removing the tumor, controlling its growth and managing your hormone levels with medications.
Not all pituitary tumors cause symptoms. Pituitary tumors that make hormones (functioning) can cause a variety of signs and symptoms depending on the hormone they produce. The signs and symptoms of pituitary tumors that don’t make hormones (nonfunctioning) are related to their growth and the pressure they put on other structures.
Large pituitary tumors — those measuring about 1 centimeter (slightly less than a half-inch) or larger — are known as macroadenomas. Smaller tumors are called microadenomas. Because of the size of macroadenomas, they can put pressure on the normal pituitary gland and nearby structures.