Pituitary Adenoma (Pituitary Tumor)

A pituitary adenoma (pituitary tumor) is an abnormal growth in the pituitary gland. The pituitary gland is a small gland in the brain. It is located behind the back of the nose. It makes hormones that affect many other glands and functions in your body. Most pituitary adenomas are not cancerous (benign). They don’t spread to other parts of your body. But they can cause the pituitary to make too few or too many hormones, causing problems in the body.

Pituitary tumors that make too many hormones will cause other glands to produce more hormones. That will cause symptoms related to each of the specific hormones. Many pituitary tumors will also press against the nearby optic nerves. This can cause vision problems.

Pituitary Adenoma (pituitary tumor) Symptoms

Most pituitary tumors don’t cause symptoms. As a result, they are not diagnosed. Or they are found only during a routine brain imaging test. About 25% of people may have small pituitary tumors without knowing it.

However, pituitary adenomas (pituitary tumors) can put pressure on the pituitary gland, nerves, brain, and other parts of the body nearby. That can cause symptoms such as:

• Eye problems due to pressure on the optic nerve, especially loss of side vision, also called peripheral vision, and double vision.
• Pain in the face, sometimes including sinus pain or ear pain.
• Drooping eyelid.
• Nausea and vomiting.

 Symptoms depend on the pituitary adenoma type and the pituitary gland’s affected area. These pituitary adenomas can lead to symptoms caused by too much or too little of the pituitary hormones. Each person may experience different symptoms. The symptoms may also mimic other health problems. Always refer to your neurosurgeon for a correct diagnosis.

Types of Pituitary Adenoma

Below are the different types of pituitary tumors:

Nonfunctional adenomas (null cell adenomas)

These null cell adenomas are the most common type. They don’t make extra hormones. You may not have any symptoms until the tumor is a specific size. When a null cell adenoma is big enough, it may cause headaches and vision problems. Large null cell adenoma can crush normal pituitary cells. This leads to symptoms caused by decreased hormone production.

Prolactinomas – Prolactin-producing tumors

These benign prolactinomas are also very common. They make too much prolactin. If you are a woman, high prolactin levels can cause your menstrual period to be irregular or even stop your period altogether. These prolactinomas can also cause you to make breastmilk, even if you are not pregnant or nursing. If you are a man, it may cause erectile dysfunction or a reduced interest in sex. You may also have a low sperm count, enlarged breasts or reduced body hair. In time, prolactinomas may cause headaches or issues with vision.

ACTH-producing pituitary tumors

ACTH (adrenocorticotropic hormone) stimulates the adrenal gland to produce steroids that affect your metabolism. These are called glucocorticoids. They reduce inflammation (redness and swelling) all over the body. They also impact your immune system, slowing it down. Too much ACTH can cause Cushing’s disease. This disease causes fat buildup in your face, neck, back, belly (abdomen), and chest. Also, your arms and legs tend to become thin. You may also have purple stretch marks and high blood pressure. These ACTH-producing pituitary tumors can also weaken your bones.

Growth hormone-producing tumors

This type of pituitary tumor produces too much growth hormone. In children, too much growth hormone stimulates the growth of almost all the bones in the body. When that happens, it is called gigantism. Gigantism can include increased height (over 7 feet), rapid growth, heavy sweating and joint pain. In adults, too much growth hormone causes a condition called acromegaly. It may include:

• Extra growth in the skull, hands, and feet
• Deepened voice
• A change in the facial appearance because of extra growth in the facial bones
• A wide spacing of teeth because of the growth of facial bones
• Joint pain
• Snoring or sleep apnea
• Diabetes or impaired glucose tolerance

Pituitary tumors that make luteinising hormone and follicle-stimulating hormone

Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are also known as gonadotropins. Pituitary tumors that make these hormones are called gonadotroph adenomas.

It’s uncommon for these adenomas to make too many hormones that then trigger symptoms. Instead, symptoms from these adenomas usually are due to tumor pressure. If symptoms do happen because of too much LH and FSH, they affect women and men differently.

Symptoms in women may include:

• Change in menstrual cycles.
• Fertility problems.
• Enlargement of and pain in the ovaries caused by a condition called ovarian hyperstimulation syndrome.

Symptoms in men may include:

• Enlarged testicles.
• Higher levels of testosterone.

Pituitary adenomas that make a thyroid-stimulating hormone

Pituitary adenomas (pituitary tumors) that make thyroid-stimulating hormones are called thyrotroph adenomas. They also may be referred to as thyroid-stimulating hormone-secreting tumors. They cause the thyroid gland to make too much of the hormone thyroxine, also called T-4. That leads to hyperthyroidism, also known as overactive thyroid disease. Hyperthyroidism can speed up the body’s metabolism causing many symptoms. Some of the most common include:

• Weight loss.
• Rapid or irregular heartbeat.
• Nervousness, anxiety or irritability.
• Frequent bowel movements.
• Sleep problems.

What causes pituitary adenoma (Pituitary tumors)?

Experts don’t know what causes pituitary adenomas (pituitary tumours). But a condition called multiple endocrine neoplasia type I (MEN 1) may raise your risk. This condition is passed down through families.

How is a pituitary adenoma (pituitary tumor) diagnosed?

Your neurosurgeon will ask about your medical history and do a physical exam. You may also need one of these tests:

• MRI. This test uses large magnets, radio waves, and a computer to make detailed images of organs and structures in your body.
• CT scan. This test uses X-rays and a computer to make images of your body.
• Blood and urine tests. These tests will check hormone levels in your blood and urine.
• Biopsy. The provider removes a tissue sample with a needle or during surgery during this test. A biopsy can indicate if cancer cells or other abnormal cells are present.

How is a pituitary adenoma tumor (pituitary tumor) treated?

Your neurosurgeon will establish the best treatment for you based on the following:

• Your age
• Your overall health and medical history
• Your symptoms
• Your ability to handle certain medicines, treatments, or therapies
• How long is the condition expected to last
• Your preferred course of treatment

Treatment may include:

• Surgery to remove the pituitary adenoma. Surgery is often a better option for smaller pituitary tumors.

• Radiosurgery (stereotactic radiosurgery) or gamma knife treatment. This uses one high dose of radiation sent right into the cancerous tissue. It causes less damage to nearby tissues. It is not surgery. But like surgery, it is a 1-session treatment that removes the pituitary tumor.

• External radiation (external beam therapy). This treatment sends high levels of radiation right to cancer cells. Special shields may be used to protect the tissue around the treatment area. These treatments are painless and usually last a few minutes.

• Medicine. Different types of treatment may be used to control how much growth hormone is made by the tumor.