How common pituitary tumors can have huge health effects
As the American Cancer Society notes, doctors diagnose about 10,000 pituitary tumors each year in the United States. However, that’s actually just a fraction of the number of tumors that people likely develop on their pituitary glands. If you picture 100 people in a room, about 10 to 15 of them could develop a pituitary tumor sometime during their lives. In fact, one review of multiple studies found that the prevalence of benign (noncancerous) pituitary tumors is approximately 17 percent.
Pituitary tumors are quite common, and some types are much more so than others. However, all pituitary tumors have one similar quality: They require an expert team to spot the symptoms, make an accurate diagnosis and provide the right treatment. Pituitary tumors are classified by the type of hormones they secrete. Each type of tumor causes different symptoms and can require different treatments.
LISTEN: Dr. Sharma discusses pituitary tumor symptoms and treatments on the Medical Intel podcast.
Prolactin-secreting pituitary tumors
Prolactin-secreting pituitary tumors, also known as lactotroph adenomas, are among the most common pituitary tumors we see. These account for about 40 percent of pituitary tumors. These tumors are functional, which means they secrete hormones—specifically prolactin, a hormone involved in the development of the glands that produce breast milk.
When a pituitary tumor produces prolactin, it throws off the body’s natural levels. In women, this can lead to a number of symptoms, including:
- Breast pain
- Feeling of breast fullness
- Irregular periods
- Unnecessary breast milk production
Men’s symptoms can include:
- Decreased hair growth
- Decreased sex drive
- Erectile dysfunction
- Low energy levels
These symptoms can appear for other reasons besides a pituitary tumor. Our first step always is to assess a patient’s hormone levels to see if they are out of normal range. If they are, we then can take the next steps to confirm whether it’s because of a pituitary tumor. We can use magnetic resonance imaging (MRI) or other scans to examine the pituitary gland and the surrounding area inside the brain.
Early diagnosis is key. Without treatment, a growing pituitary tumor can compress the pituitary gland and prevent it from releasing life-sustaining hormones, including cortisol (which affects metabolism and immune response) and thyroid-stimulating hormone (TSH, which affects the thyroid, metabolism, heart, digestive system, muscle control and other areas). A large pituitary tumor also can cause vision problems as it compresses the optic nerves, which relay information from the eyes to the brain.
We can treat 80 to 90 percent of prolactin-secreting tumors successfully with medications called dopamine agonists. These drugs shrink the tumor and, over time, keep it from releasing too much prolactin.
We used this approach to treat a young man who had been referred to the MedStar Pituitary Center after he had failed the vision test for his driver’s license. His eye doctor referred him to Dr. Martin P. Kolsky, a neuro-ophthalmologist on our team. Dr. Kolsky found that this patient had a loss of peripheral vision on both sides, which can be caused by a pituitary tumor. The patient’s MRI showed a large tumor compressing his optic nerves.
Ordinarily, large tumors require surgery. But we found that his prolactin level was close to 6,000 nanograms per milliliter (ng/ml), even though the normal level for a man is less than 23 ng/mL. This result led us to instead prescribe a medication called cabergoline, which is returning his prolactin to normal levels and shrinking his tumor. As of January 2018, his tumor was about 60 percent smaller, he had regained full vision in both eyes, and we are hopeful that the tumor will continue to shrink without the need for surgery.
Growth-hormone-secreting pituitary tumors
Growth-hormone-secreting tumors, also known as somatotroph adenomas, are a little less common. These account for 20 percent of the pituitary tumors doctors diagnose. Growth hormone, or GH, regulates the body’s normal growth processes. In children who are still growing, too much GH can lead to gigantism, which causes a child to grow very tall. However, if a patient is done growing, excessive GH can cause acromegaly, a condition that can cause:
- Changes in facial features, such as an enlarged nose, more space between the teeth or growth of the lower jaw
- Diabetes and prediabetes
- Enlarged hands and feet
- Enlarged heart, which can increase the risk of irregular heart rhythms
- High blood pressure
- Increased risk of colon polyps
- Sleep apnea
Our first step when we suspect a growth-hormone-secreting tumor is to test the patient’s hormone levels. We need to make sure they don’t have a very rare co-secreting tumor, also known as a plurihormonal adenoma, that makes more than one type of hormone.
The next step is surgery to remove the tumor. These tumors often are larger than other types because the changes in a patient’s features can be hard to notice right away and thus difficult to detect early. And sometimes, the symptoms are misdiagnosed as something else entirely.
For example, we had a patient who originally went to a dental surgeon for jaw surgery. His main complaint was that he had lost his smile. His lower jaw had started to protrude outward, and his upper teeth weren’t visible anymore when he smiled.
One of our dental surgery colleagues here at MedStar Washington Hospital Center looked at his X-rays and saw that the bone inside the skull where the pituitary gland is located looked enlarged. He referred the young man to the MedStar Pituitary Center for evaluation. Sure enough, we found high GH levels and a GH-secreting pituitary tumor. After surgery to remove it, the patient’s hormone levels are much lower, and we are continuing to lower those levels with monthly medical therapy.
Our team treatment approach for pituitary tumors
No one doctor can treat a pituitary tumor on their own. Many experts must work together when we suspect a patient has a pituitary tumor:
- An endocrinologist has to test the patient’s hormone levels
- A neuro-ophthalmologist with expertise in how these tumors affect vision
- A neuroradiologist with access to the latest MRI techniques and technology
- An experienced neurosurgeon if surgery is needed
- Radiation oncology experts with access to advanced radiosurgery tools if the patient can’t undergo neurosurgery or has residual tumor after surgery
Our pituitary tumor team discusses all the options to come up with a personalized treatment plan for each patient. We look at each patient as a whole, not a set of symptoms.
I understand the fear and nervousness that many patients have when we tell them they have a pituitary tumor. But it’s important to remember that no one needs to go through this alone. Our team’s experience with these tumors gives our patients an edge, and our top priority is to provide the care they need as quickly and safely as possible.