Overview

The pituitary gland is a small but important gland located near the brain. This gland is often referred to as the “master endocrine gland” because it secretes a variety of hormones that affect many bodily functions. A pituitary gland has two lobes, anterior (the front) and posterior (the back), and each lobe is responsible for releasing specific hormones. Examples of hormones produced by the pituitary gland include:

• Thyroid stimulating hormone (TSH), which stimulates the activity of the thyroid gland

• Adrenocorticotropic hormone (ACTH), which controls secretions of the adrenal gland that support blood pressure, metabolism, and the body’s response to stress

• Gonadotropins (FSH and LH), which act on the testicles (in males) or ovaries (in females) to stimulate production of sperm or eggs, and to regulate a woman’s menstrual cycle

• Growth hormone, which promotes growth of the long bones in the limbs (arms and legs)

• Prolactin, which stimulates milk production in women after childbirth

• Lipotropin, which stimulates the transfer of fat from the body to the bloodstream

When normal cells begin to change and grow uncontrollably, they can form a mass called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body). Generally, pituitary tumors are benign growths and are classified as pituitary adenomas. However, a pituitary gland tumor can occasionally show malignant behavior by invading nearby tissue and structures, or in rare cases, metastasis (spreading) to other parts of the body.

Pituitary gland tumors are NOT brain tumors, as the pituitary gland sits beneath and is separate from the brain. However, a tumor in this gland can be very serious, because a malfunctioning pituitary gland can cause serious symptoms in other organs or systems.

Statistics

About 8,000-10,000 pituitary tumors are diagnosed in the U.S. each year. Because the pituitary gland is located next to the brain, this type of tumor is sometimes classified as a brain tumor in data collection; due to this misclassification, pituitary gland tumors account for about 7% of the tumors reported as “primary brain tumors.” They are more common in adults and are usually benign.

Statistics should be interpreted with caution. These estimates are based on data from thousands of cases of this type of tumor in the United States, but the actual risk for a particular individual may differ. It is not possible to tell a person how long he or she will live with a pituitary gland tumor.

Source: American Cancer Society

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