Pituitary Tumors

Pituitary tumors are unusual growths that develop in the pituitary gland. This gland is an organ about the size of a pea. It’s located behind the nose at the base of the brain. Some of these tumors cause the pituitary gland to make too much of certain hormones that control important body functions. Others can cause the pituitary gland to make too little of those hormones.

Most pituitary tumors are benign. That means they are not cancer. Another name for these noncancerous tumors is pituitary adenomas. Most adenomas stay in the pituitary gland or in the tissue around it, and they grow slowly. They typically don’t spread to other parts of the body.

Pituitary tumors can be treated in several ways. The tumor may be removed with surgery. Or its growth may be controlled with medications or radiation therapy. Sometimes, hormone levels are managed with medicine. Your health care provider may suggest a combination of these treatments. In some cases, observation — also called a ”wait-and-see” approach — may be the right choice.

Types

Types of pituitary adenomas include:

• Functioning. These adenomas make hormones. They cause different symptoms depending on the kind of hormones they make. Functioning pituitary adenomas fall into several categories, including those that make:
  • Adrenocorticotropic hormone. This hormone also is known as ACTH. These tumors are sometimes called corticotroph adenomas.
  • Growth hormone. These tumors are called somatotroph adenomas.
  • Luteinizing hormone and follicle-stimulating hormone. These hormones also are known as gonadotropins. Pituitary tumors that make these hormones are called gonadotroph adenomas.
  • Prolactin. These tumors are called prolactinomas or lactotroph adenomas.
  • Thyroid-stimulating hormone. These tumors are called thyrotroph adenomas.
• Nonfunctioning. These adenomas don’t make hormones. The symptoms they cause are related to the pressure their growth puts on the pituitary gland, nearby nerves and the brain.
• Macroadenomas. These are larger adenomas. They measure about 1 centimeter or more. That’s slightly less than a half-inch. They can be functioning or nonfunctioning.
• Microadenomas. These adenomas are smaller. They measure less than 1 centimeter. That’s slightly less than a half-inch. They can be functioning or nonfunctioning.

Pituitary tumors are different from pituitary cysts. A cyst is a sac that may be filled with air, fluid or other material. A tumor is an unusual mass of cells that may grow over time. Cysts may form on or near the pituitary gland, but they are not tumors or adenomas.