Secretory Tumors

Secretory tumors and the conditions they cause include 


A prolactinoma is the most common secretory tumor, accounting for about 40 percent of pituitary tumors. This tumor produces too much prolactin, the hormone that causes milk production. Prolactinomas affect both men and women. While excess milk discharge from breasts is one of the symptoms of a prolactinoma, there are many other signs of this kind of tumor.


  • Changes in menstrual cycle (skipping periods or complete loss of periods)
  • Headaches
  • Infertility in women and men
  • Peripheral vision problems that make it hard to see well at the edges of your vision
  • Vaginal dryness or pain during intercourse
  • Reduced sex drive in women and men
  • Osteoporosis or bone loss
  • Erectile dysfunction —the inability to get or maintain an erection


About 80 to 90 percent of people with a prolactinoma can be treated successfully with a type of drug called a dopamine agonist. This kind of drug should eliminate or reduce symptoms, lower prolactin levels and usually return them to normal, help restore normal function to the pituitary, and usually reduce the tumor size.

This medication is taken as a pill. The most common side effects are nausea and dizziness. Sometimes drug treatment doesn’t work, however, so your doctor might recommend surgery. Radiation therapy is rarely used to treat tumors. Some people with very small tumors, which are not growing or causing symptoms, may be monitored carefully without treatment.

Acromegaly and gigantism

Acromegaly is a rare disease typically caused by a noncancerous tumor in the pituitary gland. Acromegaly is caused by the excess secretion of growth hormone (GH). It can cause noticeable changes in your appearance, such as enlarged hands, feet, and facial features, and increased spaces between teeth. It also can affect your metabolism. Too much GH also affects the cardiac system (leading to high blood pressure and heart disease), glucose metabolism (leading to high blood sugar), and the musculoskeletal system (leading to joint and bone problems). Symptoms of acromegaly may evolve slowly over time.  Signs of acromegaly usually begin between the ages of 30 and 50, but can occur in older or younger adults.

Gigantism is similar to acromegaly but occurs in children. Too much GH causes a child to grow to be unusually tall. Puberty may be delayed in children with gigantism.

Aside from changes in appearance, excess GH causes many symptoms.


  • Interrupted menstrual cycle
  • Deepening of the voice
  • Inability to get or maintain an erection
  • Oily skin or acne
  • Joint aches
  • Excessive sweating
  • Thicker flesh on the palms and feet
  • Fatigue
  • Headaches
  • Carpal tunnel syndrome resulting in achy wrists and hands
  • Problems seeing well at the edges of your vision
  • Reduced sex drive

It can also cause health problems such as

  • Sleep apnea, which is interrupted breathing while sleeping
  • Congestive heart failure
  • High blood pressure
  • High glucose levels or diabetes
  • Osteoarthritis or bone loss
  • Colon polyps


The best way to treat acromegaly is by removing the tumor. This is typically done through a procedure called transsphenoidal microsurgery.

The surgery is performed through the sinus passages behind your nose. Removing or reducing the pituitary tumor that causes acromegaly will reduce growth hormone levels and relieve the pressure caused by the tumor mass. Very rarely, a craniotomy (surgery that opens a section of the skull) may be needed to remove a tumor that cannot be removed through the sinuses.

Your surgeon may be unable to remove the entire tumor, depending on its size and location. If that happens, growth hormone levels usually will remain too high. If there is still tumor left or your hormone levels are not yet normal after surgery, you may receive medicine and in some cases, radiation therapy.  People who are not candidates for surgery may also receive these treatments.

The medication of choice is a long-acting somatostatin analogue, a drug that suppresses GH production.  Somatostatin analogues are given by a monthly injection in the muscle or deep under the skin.  The drug works directly on the pituitary tumor to suppress GH production. It also can shrink the size of the tumor or prevent it from getting bigger as long as you are taking it.  You may also use this medication while you are waiting for radiation to be effective, something that can take years.

Pegvisomant is a different type of medication approved for acromegaly. Instead of suppressing excess GH production by the pituitary tumor, it works to stop the hormone from acting on the body, but does not treat the tumor itself. Pegvisomant is given by a daily injection under the skin.

The speed at which symptoms disappear varies. With treatment, some symptoms such as sweating may disappear right away. Other symptoms, such as thicker tissue on your palms and feet, may take longer to reverse. If you have osteoarthritis, or bone changes, they may not go away.

Cushing's disease

Cushing's disease occurs when a pituitary tumor secretes too much ACTH, the hormone that stimulates the adrenal glands.  Too much ACTH causes the adrenal glands to produce excess cortisol.


Changes in appearance:

  • Wide, purple stretch marks on the skin (chest, armpits, abdomen, flanks)
  • Rapid and unexplained weight gain with a rounder face and abdomen
  • Increased fat in the neck and above the collarbone and upper back
  • Skin changes (bruising without injury, acne, hair growth) and red cheeks

Mood and thinking:

  • Memory loss or not being able to think clearly
  • Depression
  • Mood and behavior disorders

Other symptoms:

  • Fatigue
  • Muscle weakness
  • Menstrual cycle disorders

Cushing’s disease can also health problems such as

  • Osteoporosis
  • High blood glucose (diabetes)
  • High blood pressure
  • Blood clots in leg veins
  • Heart attack
  • Stroke
  • Fracture


The first line therapy is surgical removal of the tumor. Cure rates with an experienced pituitary surgeon are about  90 percent in people with small tumors. A patient will typically have transsphenoidal microsurgery through the nasal sinuses.

People who are not cured usually have repeat surgery. When surgery does not work, radiation therapy may treat any remaining tumor mass. Several medications to block the adrenal glands (such as ketoconazole, metyrapone or mitotane) are often used while waiting for radiation to have an effect. In some cases, a drug called a dopamine agonist can reduce ACTH levels and cortisol production. Pasireotide is another medication (given by injection under the skin) that can also reduce ACTH levels and cortisol production. Mifepristone is yet another medication that stops cortisol from working on the body. The adrenal glands are rarely removed.

TSH-secreting tumors

A TSH-secreting pituitary tumor produces too much thyroid-stimulating hormone, which then causes the thyroid gland to make too much thyroid hormone.  This leads to hyperthyroidism. These tumors are very rare.


  • Heart palpitations
  • Fast heartbeat
  • Irregular menstrual cycle
  • Headaches
  • Visual disturbances
  • Difficulty sleeping
  • More frequent bowel movements
  • Inability to tolerate heat
  • Excessive sweating
  • Fatigue
  • Weight loss
  • Shakiness
  • Nervousness


The first treatment for these tumors is usually transsphenoidal microsurgery through the nasal sinuses. Unless the tumor is large, surgery alone usually provides a complete cure.

If surgery does not remove the entire tumor, a somatostatin analogue is an effective medication to reduce TSH levels, which in turn lowers thyroid hormone levels. Radiation therapy also may be used. Radiation therapy will destroy the remaining tumor, but the process is slow. Patients also may need drug therapy to lower thyroid hormone levels, until radiation therapy takes effect.


Anne Klibanski, MD
Massachusetts General Hospital 
Harvard Medical School

Nicholas Tritos, MD
Massachusetts General Hospital
Harvard Medical School

Last Review: May 2013