Pituitary Adenoma

(Pituitary Tumor; Nervous System Tumor)

Pronounced: Pi-TU-eh-tar-E ad-eh-NO-muh


A pituitary adenoma is an abnormal growth, or tumor, in the pituitary gland. The pituitary is a small complicated gland at the base of the brain. It makes several important hormones that regulate growth and the activity of several other major glands throughout the body. A pituitary adenoma is an abnormal growth, or tumor, in this gland. Pituitary adenomas are usually benign. This means they are not cancerous. They do not spread to other parts of the body. They can lead to vision problems because they are behind and near the eyes. A pituitary adenoma can also lead to growth problems. It often can also change the hormonal balance of the thyroid, adrenal, and gonad glands.

Pituitary Gland

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Causes    TOP

The cause is unknown. Some tumors are part of other endocrine disorders and are associated with genetic changes. These can be inherited.

Tumors can also be a result of exposure to cancer-causing substances or radiation. In some cases, the DNA changes may occur for no known reason.

Risk Factors    TOP

Factors that may increase your chance of pituitary adenoma include:

  • A family or personal history of multiple endocrine neoplasia, type 1 (MEN1)—a hereditary condition that increases the risk of developing pituitary, hypothalamus, and parathyroid and pancreatic tumors
  • Other inherited disorders such as Carney complex, acromegaly, or gigantism

Symptoms    TOP

Symptoms can vary and may not be present at all. It will depend on whether the tumor is secreting hormones and how large it is. The tumor's location at the base of the brain can also cause symptoms.

General symptoms due to size may include:

  • Headache
  • Blurred vision or tunnel vision

In addition to the above, symptoms from prolactin-secreting adenoma:

  • Milk production in nonlactating women
  • Loss of or irregular periods
  • Lack of interest in sex
  • Vaginal dryness

Symptoms from thyrotropin-secreting adenoma:

  • Swelling of the neck

Symptoms of hyperthyroidism:

  • Tremors
  • Rapid heartbeat
  • Anxiety
  • Weight loss
  • Insomnia

Symptoms from corticotropin-secreting adenoma:

  • Menstrual disturbance
  • Skin changes—increased facial hair, acne, bruising, or bluish stretch marks
  • Buffalo hump—increased fatty tissue in back
  • Obesity, especially around the wrist
  • Round face

Growth hormone-secreting adenoma:

  • Enlarged hands and feet
  • Excessive growth and height
  • Oily skin
  • Excess sweating

Pituitary adenomas may also be associated with the following conditions:

Diagnosis    TOP

You will be asked about your symptoms and medical history. A physical exam will be done. You will be referred to an endocrinologist. This is a doctor who specializes in glands and hormones.

Your blood and urine may be tested.

Your peripheral vision may be tested. This can be done with visual field tests.

Images may be taken of your bodily structures. This can be done with an MRI scan.

Treatment    TOP

Treatment depends on the presence and type of hormones being secreted. It is not uncommon for these treatment options to be used in combination. Talk with your doctor about the best plan for you.

Treatment options include:


Surgery is often done to remove the tumor. The rest of the normal pituitary gland may be damaged during surgery. This can be treated with hormone replacement.


Medications can control symptoms and sometimes shrink the tumor. They can block hormone secretion.

Medications may be useful for the majority of adenomas that are prolactin or growth hormone-secreting.

Radiation Therapy    TOP

Radiation therapy involves the use of radiation to kill tumor cells. The types of radiation therapy used to treat pituitary adenomas include:

  • Conventional therapy—radiation is directed at the pituitary from a source outside the body
  • Stereotactic radiosurgery—an intense radiation beam is targeted directly at the tumor
  • Proton beam radiotherapy—a beam of protons (positively charged particles) is directly focused on the tumor

Prevention    TOP

There are no current guidelines to prevent a pituitary adenoma.


American Cancer Society
Hormone Health Network—Endocrine Society


Canadian Cancer Society
Brain Tumor Foundation of Canada


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General information about pituitary tumors. National Cancer Institute website. Available at:
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Updated January 3, 2014. Accessed February 27, 2014.
NINDS pituitary tumors information page. National Institute of Neurological Disorders and Stroke website. Available at:
...(Click grey area to select URL)
Updated February 14, 2014. Accessed February 27, 2014.
Pituitary tumors. American Cancer Society website. Available at:
...(Click grey area to select URL)
Accessed February 27, 2014.
Pituitary tumors. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T900666/Pituitary-tumors. Updated January 23, 2015. Accessed September 27, 2016.
Last reviewed March 2017 by EBSCO Medical Review Board Kim Carmichael, MD
Last Updated: 4/29/2014

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