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There are a number of secretory tumors that are troublesome to people. A prolactinoma is the most common, accounting for about 40 percent of pituitary gland tumors. This is a tumor on the pituitary gland that produces too much prolactin, the milk hormone. While excess milk discharge from breasts is one of the symptoms of a prolactinoma, there are many other signs of this kind of tumor.
About 80 to 90 percent of prolactinoma patients can be treated successfully with a dopamine agonist drug. The use of this kind of drug should eliminate or reduce symptoms of a high prolactin level, return your prolactin levels to normal, help restore normal function to the pituitary, and usually reduce the pituitary gland tumor size.
This medication is taken in tablet form. Your doctor will monitor your prolactin levels and make adjustments, if necessary, depending on prolactin levels symptoms and tumor size. The most common side effects are nausea and dizziness. Sometimes drug treatment is ineffective, however, so your doctor might recommend surgery. Radiation therapy is rarely used with large tumors. Some patients with very small tumors, which are stable in size and do not have any associated 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. The disease is caused by the hypersecretion of growth hormones and the ensuing hormone imbalance. It can cause noticeable changes in your appearance. It also can affect your metabolism, which is the process through which your body breaks down food, uses or stores food components, and eliminates waste products. Too much growth hormone also affects the cardiac system, glucose metabolism, joints, and bones. Symptoms of acromegaly may evolve slowly, over time. A relative who has not seen you in a while may notice the changes that are part of this condition. Indications of acromegaly usually begin between the ages of 30 and 50.
Gigantism is similar to acromegaly but occurs in children. When the condition begins at a young age, before a child's growth plates have closed, that child may grow to be unusually tall. Puberty may be delayed in children with this disorder.
The best way to treat acromegaly is by removing the tumor. This is typically achieved 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. A craniotomy may be required on very rare occasions to remove a tumor that cannot be removed through a transsphenoidal method.
Your surgeon may be unable to remove the entire pituitary gland tumor. If that happens, your hormone levels will be tested. If there is still a tumor left or your hormone levels are not yet normal, medicine and/or radiation therapy may be given.The medication of choice is octreotide, which is given most often by a monthly intramuscular injection. This therapy may be given to control overproduction of growth hormone after non-curative surgery, or in patients who are not surgical candidates. It also may be used while you are waiting for radiation to be effective, something that can take years.
A new medication called pegvisomant has now been approved for acromegaly. Instead of eliminating the extra growth hormone by the pituitary tumor, it works to stop the hormone from acting on the body. It is given by a daily injection.
The speed at which symptoms disappear varies. With treatment, some symptoms such as sweating may disappear immediately. Hypertension or abnormal glucose, when due to excess GH may also quickly subside when GH levels become normal. Other indications, 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.
NOTE: Acromegaly puts you at risk for colon polyps. Your doctor should screen you for colon cancer and look for pre-cancerous growths in the colon, called polyps. Because the risk is high for this type of cancer, you should have a colonoscopy regularly.
Cushing's disease occurs when a pituitary tumor is associated with hypersecretion of pituitary ACTH, causing too much cortisol by the adrenal glands. While Cushing's disease is uncommon, it is significant in that it affects as many as 4,000 people each year in the United States.
An individual with Cushing's disease must have personalized treatment, tailored to his or her needs. This treatment may mean a combination of medication, surgery, and radiation. The first line therapy is surgical and cure rates with an experienced neurosurgeon are more than 90 percent. A patient will typically have transsphenoidal microsurgery through the nasal sinuses.
Patients who are not cured but have proven pituitary Cushing's disease usually have repeat surgery. When surgery does not work, radiation therapy may treat any remaining tumor mass. Medication to block the adrenal glands is typically used while waiting for the radiation to have an effect. The adrenal glands are rarely removed. Your doctor may prescribe additional medication to treat high blood pressure, high glucose levels, or additional problems brought on by this disorder.
A TSH-secreting pituitary gland tumor secretes too much thyroid-stimulating hormone, which then causes the thyroid gland to become overactive and make too much thyroid hormone, causing hyperthyroidism. These tumors are very rare.
The first treatment for these tumors is usually transsphenoidal microsurgery, through the nasal sinuses. Unless the tumor is large, surgery alone can typically provide a complete cure. Even so, you will need a long follow-up period with your doctor to be sure the treatment has worked.
If surgery does not remove the entire tumor, octreotide is an effective medication. Radiation therapy also may be prescribed. The radiation will destroy the remaining tumor, but the process is slow. Patients also may need additional drug therapy to lower thyroid hormone levels.