What Is Pheochromocytoma?

Pheochromocytoma is a type of neuroendocrine tumor that forms in the adrenal glands, two small organs that sit on top of each kidney.

These growths produce excess fight-or-flight hormones called catecholamines. This influx of hormones can lead to symptoms such as high blood pressure, sweatiness, headaches, and palpitations—often in discrete episodes called paroxysms.

Pheochromocytomas are very rare, with only two to eight cases diagnosed per 1 million people each year. They are most commonly found in people between the ages of 30 and 50, with roughly 10% occurring in children.

Most pheochromocytomas are benign (noncancerous), but even benign pheochromocytomas can be dangerous due to their secretion of hormones. Fewer than 10% of pheochromocytomas are malignant (cancerous).

While a surge in catecholamine hormones is uncommon, it's important to be aware of the symptoms since the condition is frequently misdiagnosed and can be fatal if not promptly treated.

This article will review the common symptoms of pheochromocytoma, its causes, diagnostic process, treatment options, and prognosis.

Symptoms of a Pheochromocytoma

Pheochromocytomas secrete excess amounts of catecholamine hormones, including epinephrine (adrenaline), norepinephrine (noradrenaline), dopamine, and sometimes other peptide hormones. These hormones work to regulate functions like blood pressure, heart rate, and the immune system.

The most common symptom of pheochromocytoma is high blood pressure (hypertension). In one study, almost 80% of people with pheochromocytomas had high blood pressure, and 53% had the classic triad of high blood pressure, sweating, and headaches.

High blood pressure due to pheochromocytoma tends to be severe, and it may occur suddenly in people who do not have any risk factors for it.

Other common symptoms occurring in 50% or more of people include:

• Headaches
• Sweating
• Palpitations
• Tremor
• Anxiety/nervousness

In around 60% of people, these symptoms occur in paroxysms, which may occur as often as a few times a day or as seldom as every few months. High blood pressure may be present between paroxysms (chronic high blood pressure) or only occur during the episodes.

Pheochromocytoma is one of the medical causes of a sense of impending doom, and these paroxysms can be very frightening.

Causes of Pheochromocytoma

Roughly 60% of pheochromocytomas occur sporadically, with up to 40% now thought to be related to germline (hereditary) mutations (mutations that are present in genes at birth).

Hereditary pheochromocytomas tend to occur in people younger than age 30 and are more likely to be bilateral (occurring in both adrenal glands). Some of these tumors are also more likely to be malignant than tumors that occur sporadically.

Among tumors that are not associated with a genetic syndrome, no known environmental or lifestyle risk factors have been identified, and the disease does not seem to vary based on dietary practices.

How Pheochromocytoma Is Diagnosed

Over 50% are pheochromocytomas are found incidentally, when an imaging scan reveals a mass in the adrenal gland.

If a pheochromocytoma is suspected due to symptoms such as high blood pressure, your health provider will take your medical history and do a physical examination.

Taking a family history is also very important. In one study, 9.5% of individuals diagnosed with pheochromocytoma had a family history of one of the genetic syndromes associated with the disease.

Your healthcare provider will also likely order lab tests and imaging scans.

Laboratory Tests

Most pheochromocytomas secrete catecholamines that can be measured (or their breakdown products can be measured) in blood and urine. Tests include:

Blood tests: In people who are at a higher risk for having a pheochromocytoma (for example, they have one of the genetic syndromes), blood testing for catecholamines is done first. This test is more sensitive than a urine test, but also more likely to result in false-positive results (results that indicate the presence of a condition, when the person does not actually have the condition).

Urine analysis: In those who do not have a genetic syndrome (or those who have not had an imaging test showing a tumor), the test of choice is urine catecholamines. This test is less sensitive, but also less likely to give false-positive readings. Urine is collected each time a person urinates for 24 hours and then evaluated in the lab.

Imaging

After a biochemical diagnosis has been made with blood tests, imaging studies are done to locate the tumor. Tests may include:

Computed tomography (CT) scan: A CT scan combines many X-ray images to create a 3-dimensional view of the organs and other soft tissue in a specific region of the body. CT is considered the best test to locate a pheochromocytoma.

Magnetic resonance imaging (MRI): An MRI may be somewhat less accurate than a CT but may be preferred in children and young adults to reduce radiation exposure.

Scintigraphy (MIBG scan): Most of the time a pheochromocytoma can be located with CT or MRI. If a tumor is not seen but strongly suspected, this nuclear imaging study may be done.

In this type of scan, a small amount of radioactive material is injected into a vein where it is taken up by neuroendocrine cells such as those in a pheochromocytoma. A camera that can detect radioactivity is then used to see if a tumor is present in the adrenal gland. This scan may also be done if a tumor is suspected to be metastatic (if it has spread, or metastasized).

Staging

Pheochromoctyomas are defined by three stages:

• Local: The tumor is present where it originated and has not spread beyond the adrenal gland.
• Regional: The tumor may have spread to nearby tissues or lymph nodes.
• Metastatic: The tumor has spread to distant sites.
  

What Are the Treatment Options?

The treatment of a pheochromocytoma depends on the stage of the disease, with surgery being the optimal treatment whenever possible. Treatment may also include chemotherapy, radiation therapy, or other therapies if the tumor has spread.

Surgery

Surgery to remove the affected adrenal gland (adrenalectomy), as well as any suspicious lymph nodes or nearby tissues, is the treatment of choice for tumors that have not spread (are not metastatic).

However, surgery should not be performed immediately. Since surgery can lead to a sudden, dangerous rise in blood pressure, medical treatment to block the release of catecholamines must be started first.

Laparoscopic surgery is the preferred method for removal. This minimally invasive procedure is done using a thin, camera-equipped surgical tool that is inserted through a small incision in the abdomen.

If tumors are present in both adrenal glands, management must be individualized. Many physicians try to save part of an adrenal gland as it is very uncommon for these tumors to be cancerous.

If both adrenal glands are removed, lifelong therapy is required to replace the hormones lost. Even with replacement, people may still develop acute adrenal crisis (Addisonian crisis), a condition in which the body doesn't have enough adrenal hormones to regulate body functions.

Additional Treatment Options

Radiopharmaceuticals: A radiopharmaceutical is often recommended first for people with metastatic tumors. In this therapy, a radioactive substance that accumulates in pheochromocytoma tumor cells is injected into a vein. It then travels to the tumor, and when taken up by the tumor cells, it gives off radiation that causes the cells to die.

Chemotherapy: For tumors that are growing rapidly, chemotherapy, using a combination of several drugs designed to kill cancer cells, is often used. These medications may be given orally by pill, or by intravenous (IV, within a vein) infusion.

Targeted therapies: Targeted therapies are drugs that specifically target cancer cells or a pathway involved in their growth. Oncologists (doctors who specialize in cancer treatment) have had some success using the drug Sutent (sunitinib) in people with pheochromocytoma.

Immunotherapy: Immunotherapy drugs are medications that use the immune system or principles of the immune system to treat tumors. It has been successful with some other types of tumors. Their use is just beginning to be explored with pheochromocytoma, but at least one study has found that an immunotherapy drug (in combination with a targeted therapy) helped to slow or stop the progression (growth) of a metastatic pheochromocytoma, extending patients' life expectancy.

Prognosis for Pheochromocytoma

The prognosis, or outcome, of pheochromocytoma can vary widely, depending on the stage (size of the tumor and how far it has spread) at diagnosis, whether the tumor is benign or malignant, and your overall health.

For those who have benign tumors that do not recur, life expectancy is similar to the general population.

For people who have localized tumors, between 7% and 17% will develop a recurrence. The five-year survival rate for metastatic pheochromocytoma or a local/regional pheochromocytoma that later recurs is 40%–45%.

Strategies for Coping

Coping with any type of tumor is challenging, but having a rare tumor that few understand can add a further sense of isolation.

Since these tumors are rare, it's relatively unlikely that you will have a local support group in your community. Fortunately, the Internet now allows people to interact with others facing a similar diagnosis worldwide. Some options of organizations that specifically support people with these tumors include:

• The Pheo Para Alliance
• North American Endocrine Tumor Society (NANETS)
• The Healing NET Foundation
• Neuroendocrine Cancer Awareness Network

Summary

Pheochromocytoma is a rare tumor that forms in the adrenal glands. This tumor produces excess levels of hormones called catecholamines that regulate functions like blood pressure, heart rate, and the immune system. High blood pressure is a common symptom of this tumor.

Diagnosing a pheochromocytoma usually involves a physical exam, blood work, urine analysis and imaging tests. Surgery to remove the tumor and the affected adrenal gland is the preferred treatment method, but chemotherapy, radiation, targeted therapy, and immunotherapy may also be used.

A Word From Verywell

Pheochromocytoma is a rare tumor, but since the signs and symptoms these tumors cause can be dangerous, it's important to be aware of the possibility of getting this diagnosis. While symptoms of high blood pressure, palpitations, and anxiety are all common, if they occur together, especially in episodes, it's important to talk to your healthcare provider.

With any medical condition, being your own advocate is a must in today's medical climate. Having an understanding of symptoms of pheochromocytoma may aid in your diagnosis. Knowing about the condition will also help you ask the right questions to get the care you deserve.