Pituitary Tumors

What are pituitary tumors?
According to The National Institute of Diabetes and Digestive and Kidney diseases, autopsy studies indicates that 25 percent of the US population has some form of small pituitary tumor. The vast majority of these are benign and not considered clinically significant. Only a very small number of people (about 14 in 100,000) experience health effects attributable to pituitary tumors.

What are symptoms of pituitary tumors?
Symptoms vary depending upon what type of tumor is growing and what area of the pituitary gland is affected. Pituitary tumors can cause symptoms which are associated with excess production of pituitary hormones and symptoms associated with reduced production of pituitary hormones. Each individual also experiences symptoms differently, and the symptoms many resemble other conditions or medical problems. Consult a physician for diagnosis.

Causes and types of tumors:
Researchers do not know at this time what causes pituitary tumors.

The most common type of pituitary tumor is called an endocrine inactive tumor, which destroys some of the hormone-producing cells in the pituitary. An endocrine inactive tumor causes hypopituitarism, or an underactive pituitary gland, which may lead to failure of sexual function, reduced sperm production, and cessation of a woman's menstrual period.

Another common pituitary tumor is called a prolactinoma, a benign tumor that produces the prolactin hormone. Prolactin stimulates breastmilk production after childbirth. According to NIDDK, 40 percent of all pituitary tumors are prolactinomas.

Other types of tumors act on other parts of the pituitary, with varying effects.

How are pituitary tumors diagnosed?
In addition to a complete medical history and medical examination, diagnostic procedures for pituitary tumors may include:

  • measurement of hormone levels in the blood

  • computed tomography (CT or CAT scan) - a non-invasive procedure that takes cross-sectional images of the brain or other internal organs; to detect any abnormalities that may not show up on an ordinary x-ray

  • magnetic resonance imaging (MRI) - a non-invasive procedure that produces two-dimensional views of an internal organ or structure, especially the brain or spinal cord

How are pituitary tumors treated?
Specific treatment for pituitary tumors will be determined by your physician based on:

  • your overall health and medical history
  • extent of the disease
  • your tolerance for specific medications, procedures, or therapies
  • expectations for the course of the disease
  • your opinion or preference

Treatment may include:

  • surgical removal of the tumor
  • radiation therapy
  • hormone-replacement therapy
  • medication (i.e., bromocriptine - a drug which acts on hormone-producing tumors to suppress its hormone-producing function)


This content was last reviewed by a University of Maryland Medicine expert on
May 14, 2003