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Pituitary Adenomas

< Brain and Spine Cancer

Pituitary Adenomas

About Pituitary Adenomas

A pituitary tumor is a growth of abnormal cells in the tissues of the pituitary gland.

Pituitary tumors form in the pituitary gland, a pea-sized organ in the center of the brain, just above the back of the nose. The pituitary gland is sometimes called the "master endocrine gland " because it makes hormones that affect the way many parts of the body work. It also controls hormones made by many other glands in the body.

Pituitary tumors are divided into three groups:

Benign pituitary adenomas:

Tumors that are not cancer. These tumors grow very slowly and do not spread from the pituitary gland to other parts of the body.

Invasive pituitary adenomas:

Benign tumors that may spread to bones of the skull or the sinus cavity below the pituitary gland.

Pituitary carcinomas:

Tumors that are malignant (cancer). These pituitary tumors spread into other areas of the central nervous system (brain and spinal cord) or outside of the central nervous system. Very few pituitary tumors are malignant.

Pituitary tumors may be either non-functioning or functioning.

  • Non-functioning pituitary tumors do not make extra amounts of hormones.
  • Functioning pituitary tumors make more than the normal amount of one or more hormones. Most pituitary tumors are functioning tumors. The extra hormones made by pituitary tumors may cause certain signs or symptoms of disease.


Signs of a pituitary tumor include problems with vision and certain physical changes. Signs and symptoms can be caused by the growth of the tumor and/or by hormones the tumor makes or by other conditions. Some tumors may not cause signs or symptoms. Check with your doctor if you have any of these problems.

Signs and symptoms of a non-functioning pituitary tumor

Sometimes, a pituitary tumor may press on or damage parts of the pituitary gland, causing it to stop making one or more hormones. Too little of a certain hormone will affect the work of the gland or organ that the hormone controls. The following signs and symptoms may occur:

  • Headache.
  • Some loss of vision.
  • Loss of body hair.
  • In women, less frequent or no menstrual periods or no milk from the breasts.
  • In men, loss of facial hair, growth of breast tissue, and impotence.
  • In women and men, lower sex drive.
  • In children, slowed growth and sexual development.

Most of the tumors that make LH and FSH do not make enough extra hormone to cause signs and symptoms. These tumors are considered to be non-functioning tumors.

Signs and symptoms of a functioning pituitary tumor

When a functioning pituitary tumor makes extra hormones, the signs and symptoms will depend on the type of hormone being made.

Too much prolactin may cause:

  • Headache.
  • Some loss of vision.
  • Less frequent or no menstrual periods or menstrual periods with a very light flow.
  • Trouble becoming pregnant or an inability to become pregnant.
  • Impotence in men.
  • Lower sex drive.
  • Flow of breast milk in a woman who is not pregnant or breast-feeding.

Too much ACTH may cause:

  • Headache.
  • Some loss of vision.
  • Weight gain in the face, neck, and trunk of the body, and thin arms and legs.
  • A lump of fat on the back of the neck.
  • Thin skin that may have purple or pink stretch marks on the chest or abdomen.
  • Easy bruising.
  • Growth of fine hair on the face, upper back, or arms.
  • Bones that break easily.
  • Anxiety, irritability, and depression.

Too much growth hormone may cause:

  • Headache.
  • Some loss of vision.
  • In adults, acromegaly (growth of the bones in the face, hands, and feet). In children, the whole body may grow much taller and larger than normal.
  • Tingling or numbness in the hands and fingers.
  • Snoring or pauses in breathing during sleep.
  • Joint pain.
  • Sweating more than usual.
  • Dysmorphophobia (extreme dislike of or concern about one or more parts of the body).

Too much thyroid-stimulating hormone may cause:

  • Irregular heartbeat.
  • Shakiness.
  • Weight loss.
  • Trouble sleeping.
  • Frequent bowel movements.
  • Sweating.

Other general signs and symptoms of pituitary tumors:

  • Nausea and vomiting.
  • Confusion.
  • Dizziness.
  • Seizures.
  • Runny or "drippy" nose (cerebrospinal fluid that surrounds the brain and spinal cord leaks into the nose).

Risk Factors

Having certain genetic conditions increases the risk of developing a pituitary tumor.

Risk factors for pituitary tumors include having the following hereditary diseases:

  • Multiple endocrine neoplasia type 1 (MEN1) syndrome.
  • Carney complex.
  • Isolated familial acromegaly.