(Pituitary Tumor, Nervous System Tumor)
The pituitary gland is a small organ located at the base of the brain that makes hormones that regulate growth and the activity of most other glands in the body. A pituitary adenoma is an abnormal growth, or tumor, in the pituitary gland. Pituitary adenomas are benign (not cancerous), and do not spread to other parts of the body. Pituitary adenomas can lead to nerve damage, growth disturbances, and changes in hormonal balance.
The cause of pituitary adenoma is unknown. Some pituitary tumors, however, have been associated with mutations in DNA (the genetic material that instructs cells what to do). These mutations can be inherited, occur as a result of exposure to cancer-causing substances, or may occur for no apparent reason.
A family or personal history of multiple endocrine neoplasia, type 1 (MEN1)—a hereditary condition that increases the risk of developing pituitary, hypothalamus, and parathyroid tumors—increases your chances of developing a pituitary adenoma. If you have this condition, be sure to tell your doctor.
Symptoms of pituitary adenomas can vary considerably, largely depending on whether or not the tumor is secreting one or more of a variety of hormones. Even if the tumor is not producing any hormones, its location at the base of the brain can cause significant symptoms.
Symptoms may include :
- Double or blurred vision
- Loss of peripheral vision
- Sudden blindness
- Loss of consciousness
- Unexplained weight changes
- Erectile dysfunction in men
- Decreased sexual desire, especially in men
- Growth of skull, hands, and feet
- Deepening of voice
- Changes in facial appearance (due to changes in facial bones)
- Wider spacing of teeth
- Joint pain
- Increased sweating
- Purple stretch marks on the abdomen
- Increased hair growth
- Fat deposits where the neck meets the spine
- Moodiness or depression
- Easy bruising
- Palpitations (rapid or irregular heartbeat)
- Increased appetite
- Feeling warm or hot
- Difficulty falling asleep
- Frequent bowel movements
- Lump in the front of the neck (enlarged thyroid)
Of course, these symptoms may be caused by other, less serious health problems and do not necessarily indicate the existence of a pituitary adenoma.
Pituitary adenomas may also be associated with the following conditions:
- Diabetes mellitus
- Kidney stones
- Cardiovascular disease
- High blood pressure
- Thyroid disease
Your doctor will ask about your symptoms and medical history, and perform a physical exam. You may be referred to an endocrinologist, a doctor who specializes in diseases of the endocrine glands and their hormones. Tests may include:
- Blood Tests–to measure hormone levels, blood sugar levels, and to identify other underlying conditions that may be causing your symptoms
- Urine Tests–to measure excretion levels of certain pituitary gland hormones
- Visual Field Tests–to check for problems with peripheral vision
- Venous Blood Sampling–small tubes (catheters) are guided through veins in the groin to the veins draining the pituitary to draw blood samples from both sides; tests are performed to see which side contains the adenoma
- CT Scan–a type of x-ray that uses a computer to make pictures of structures inside the brain
- MRI Scan–a test that uses strong magnets and radio waves to create pictures of structures inside the brain
Treatment for a pituitary adenoma depends on the presence and identification of hormones being secreted. It is not uncommon for these treatment options to be used in combination. Talk with your doctor about the best treatment plan for you.
Treatment options include:
The most common treatment for a pituitary adenoma is surgery to remove the tumor. If the pituitary gland is damaged during surgery, it can be treated with medications to replace certain hormones produced by the pituitary.
Medications that block hormone secretion can control symptoms and sometimes shrink the tumor.
Radiation therapy involves the use of radiation to kill tumor cells. The types of radiation therapy used to treat pituitary adenomas 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 (positively charged particles) is directly focused on the tumor
There are no guidelines for preventing a pituitary adenoma.