Pituitary Tumors

Definition

A pituitary adenoma is a growth (tumor) in the pituitary gland. The pituitary is a small gland at the base of the brain. It makes chemicals called hormones. Hormones control other glands in the body.

Pituitary adenomas are usually not cancer. They do not spread. However, they can lead to vision and growth problems. They can also change the balance of hormones of the thyroid, adrenal, and gonad glands.

Pituitary Gland

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Causes

Changes in cells cause the growth of a tumor. It is not always clear what causes these changes. It may be due to genes or the environment.

Risk Factors

Things that may raise the risk of a pituitary adenoma are:

• A family or personal history of multiple endocrine neoplasia, type 1 (MEN1)
• Other inherited disorders such as:

Symptoms

Symptoms can vary. They depend on the size of the tumor. They also depend on if the tumor is sending out hormones. The tumor can also cause problem because it is at the base of the brain. Some may not have any symptoms.

Symptoms due to size may include:

• Headache
• Blurred vision or tunnel vision

A prolactin-secreting adenoma may cause:

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

A thyrotropin-secreting adenoma may cause swelling of the neck.

If the adenoma causes hyperthyroidism it may lead to:

• Tremors
• Fast heartbeat
• Anxiety
• Weight loss
• Problems sleeping

A corticotropin-secreting adenoma may cause:

• Menstrual changes
• Skin changes such as more face hair in women, acne, bruising, or bluish stretch marks
• Buffalo hump, an increase in fatty tissue on the back
• Obesity, especially around the wrist
• Round face

A growth hormone-secreting adenoma may cause:

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

Pituitary adenomas may also play a role in:

• Diabetes
• Kidney stones
• Cardiovascular disease
• High blood pressure
• Osteoporosis

Diagnosis

The doctor will ask about symptoms and past health. A physical exam will be done. An endocrinologist is a specialist. They work with gland and hormone problems. They may order tests such as:

• Blood and urine tests to check hormone levels
• Vision tests
• Images of brain which may be done with an MRI

Treatment

Treatment will depend on the size and impact of the tumor. Tumors that are not causing problems may not need immediate treatment. The doctor will schedule regular exams to track any changes.

Treatment may focus on managing hormone changes caused by the tumor or tumor removal. A combination of treatments may be used. Options may include:

Surgery

Tumors that are pressing on nearby structures may need to be removed. Many may be removed through the nose. Healthy pituitary gland tissue may also be removed. Hormone medicine may be needed after surgery.

Medicine

Medicines can control symptoms and sometimes shrink the tumor. They can also block hormones from the tumor.

Medicine may be useful for prolactin or growth hormone-secreting adenomas.

Radiation Therapy

Radiation therapy can kill tumor cells. The types of radiation therapy used may 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 is focused on the tumor

Prevention

There are no guidelines to prevent this condition.

References

• General information about pituitary tumors. National Cancer Institute website. Available at: http://www.cancer.gov/types/pituitary/patient/pituitary-treatment-pdq.
• Marques JVO, Boguszewski CL. Fertility issues in aggressive pituitary tumors. Rev Endocr Metab Disord. 2020;21(2):225-233 .
• NINDS pituitary tumors information page. National Institute of Neurological Disorders and Stroke website. Available at: https://www.ninds.nih.gov/health-information/disorders/pituitary-tumors.
• Nonfunctioning pituitary adenoma. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/nonfunctioning-pituitary-adenoma.
• Pituitary tumors. American Cancer Society website. Available at: https://www.cancer.org/cancer/pituitary-tumors.html.