Pheochromocytoma
Overview
A pheochromocytoma is a rare tumor that starts in cells in the adrenal medulla, the central part of the adrenal glands. The adrenal medulla makes and releases epinephrine (also known as adrenaline) and norepinephrine (or noradrenaline). These two hormones help regulate blood pressure, heart rate, sweating, and more broadly, the body’s response to stress.
In people with pheochromocytomas, the cells that make up the tumors produce and release excessive levels of these hormones, which can lead to high blood pressure, heart palpitations, sweating, and headache, among other symptoms. Left untreated, pheochromocytomas can lead to life-threatening high blood pressure and other serious complications, such as heart attack or stroke.
Pheochromocytomas can affect people of any age, but they are typically diagnosed among those in their 30s and 40s. The tumors are usually benign, or noncancerous; however, up to 20% of cases are cancerous and can metastasize (i.e., spread to other parts of the body).
Fortunately, treatments are available. Medications can help control blood pressure and heart rate, and surgical removal of the tumors can relieve symptoms and even cure people of the condition.
“Although pheochromocytomas can cause serious complications, when diagnosed appropriately, they are usually effectively and completely cured by surgical removal,” says Smilow Cancer Hospital endocrine surgeon Courtney Gibson, MD.
What is a pheochromocytoma?
Adrenaline, noradrenaline (also known as epinephrine and norepinephrine) and dopamine are hormones called catecholamines, which influence many normal functions of the body. Most notably, they regulate heart rate, blood pressure, breathing, digestion, sweating, urination, and sexual arousal. In times of stress or danger, catecholamines increase blood sugar to supply the brain and muscle with energy. Catecholamines control the "fight or flight" response, which allows the body to react to stressful situations. These substances are made by the adrenal glands and in nerve tissue elsewhere in the body.
A pheochromocytoma is an adrenal tumor that makes and releases excess catecholamines. These tumors can cause serious health problems including stroke, heart attack, and even death.
Pheochromocytomas are rare, occurring in about 2 to 8 out of every one million people.
Approximately 10% of patients are found to have pheochromocytomas in both adrenal glands, which is most commonly seen in younger patients with pheochromocytoma-related genetic syndromes.
What causes pheochromocytoma?
More than half of pheochromocytomas arise sporadically, meaning they are not linked to an inherited disorder; their cause is unknown.
However, about 30% of pheochromocytomas are linked to inherited conditions or genetic mutations that predispose people to the disease. People who have a family history of pheochromocytoma or paraganglioma (a related type of tumor) may be at increased risk for pheochromocytoma. Certain genetic disorders, including multiple endocrine neoplasia type 2 (MEN2), neurofibromatosis type 1 (NF1), and von Hippel-Lindau (VHL) disease, are also associated with increased risk for the condition.
What are the symptoms of pheochromocytoma?
People with a pheochromocytoma often do not have any symptoms.
When symptoms occur, they can include:
- High blood pressure (blood pressure may remain elevated for prolonged periods or it may occur in episodes that last for minutes to hours)
- Headache
- Heart palpitations and rapid heartbeat
- Excessive sweating
- Shortness of breath
- Anxiety and/or panic
- Pale skin
- Nausea
- Weakness
- Weight loss
- Gastrointestinal upset (i.e., diarrhea, bloating, stomach pain)
These symptoms occur when the tumor secretes hormones. This can happen with varying frequency, from once per month to several times per day. Pheochromocytomas tend to grow over time, and as they get larger, symptoms may be more severe, last longer, and occur more frequently.
How are pheochromocytomas diagnosed?
To diagnose a pheochromocytoma, your doctor will review your medical history, conduct a physical exam, and order one or more diagnostic tests.
Your doctor may begin to make a diagnosis by asking about symptoms, when they began, and how frequently they occur. They may also ask about a family history of pheochromocytoma or a genetic disorder that has been linked to the disease. During the physical exam, your blood pressure and heart rate will be checked, as well as your skin for signs of paleness or sweatiness.
Additional tests are necessary to confirm a pheochromocytoma diagnosis, including blood and/or urine tests to measure whether the levels of hormones and other compounds are elevated. If these tests confirm that a pheochromocytoma is present, your doctor will order an imaging test to locate the tumor.
Imaging tests may include a computed tomography (CT) scan or a magnetic resonance imaging (MRI) scan of the abdomen. If the pheochromocytoma cannot be located with a CT or MRI scan, you may have an abdominal positron emission tomography (PET) scan or MIGB (metaiodobenzlguanidine) scintiscan. These latter imaging tests require an injection of a small amount of radioactive material that allows doctors to better see the pheochromocytoma.
If you are diagnosed with a pheochromocytoma, you may undergo a genetic test to determine if you have a genetic mutation or a genetic disorder that makes you more susceptible to pheochromocytomas and other types of tumors. Because mutations can be passed to children, genetic testing can help identify whether other family members may be at increased risk for pheochromocytoma.
How are pheochromocytomas treated?
Surgical removal of the tumor is the main treatment for pheochromocytoma. Usually, several weeks before the surgery, patients begin taking medications to lower and stabilize their blood pressure and heart rate. They may also need to follow a high-sodium diet and drink plenty of fluids to increase blood volume in the weeks leading up to the surgery.
Surgery for pheochromocytoma involves a total adrenalectomy, a procedure in which one or both adrenal glands are completely removed. In other cases, surgeons may perform a partial adrenalectomy, also known as cortical-sparing surgery, in which the adrenal medulla and some surrounding tissues are removed, while leaving part of the outer section of the adrenal gland—known as the adrenal cortex—intact. This preserves the ability of the adrenal cortex to continue making and secreting hormones that help regulate blood pressure, salt balance, and other essential functions. Patients who have both adrenal glands completely removed will need to take steroid medications for the rest of their life.
Most adrenalectomies, whether total or partial, can be done using minimally invasive techniques. In these procedures, a surgeon makes three or four small incisions, either on the abdomen (laparoscopic) or the back (retroperitoneoscopic). A thin tube, equipped with a light and camera—called a laparoscope—and other surgical tools are inserted into the incisions. The surgeon uses the laparoscope to view the adrenal gland and performs the adrenalectomy using surgical tools. If the pheochromocytoma is large or invasive, the procedure may need to be converted to an open procedure, which involves a much larger incision than minimally invasive approaches, and typically involves a longer recovery period.
Cancerous pheochromocytomas are rare and usually require multimodal therapy with surgery, radiation therapy, and chemotherapy.
What is the outlook for people who have a pheochromocytoma?
Without treatment, pheochromocytomas can lead to life-threatening high blood pressure and complications including heart attack, heart arrhythmias, pulmonary edema, heart failure, and stoke, among others.
With treatment, the outlook is better. In many cases, surgical removal of the tumor can cure people of the disease. Some people, however, may still have high blood pressure even after surgery. This can be treated with medication.
There is also a risk that the tumor will return after surgery. This can happen years after initial treatment. Because of this risk, people who have been treated for pheochromocytoma should get regular check-ups to monitor the possible return of the disease.
For people with cancerous pheochromocytoma that has spread to other parts of the body, the five-year survival rate ranges from 34% to 60%.
What is unique about Yale Medicine's approach to pheochromocytomas?
“At Yale, we provide a robust multidisciplinary approach to the treatment of pheochromocytomas, with involvement of experienced clinicians in the fields of medical endocrinology, endocrine surgery, radiology, and anesthesiology,” says Dr. Gibson. “Additionally, we perform these procedures through a minimally invasive, retroperitoneoscopic approach, which leads to speedier recovery, less time in the hospital, and less time away from work and home life. These factors make Yale Medicine a center of excellence in the treatment of pheochromocytomas.”