Overview

A pheochromocytoma (fee-o-kroe-moe-sy-TOE-muh) is a rare, usually noncancerous (benign) tumor that develops in an adrenal gland. Usually, this type of tumor affects one of your two adrenal glands, but it can affect both.

If you have a pheochromocytoma, the tumor releases hormones that cause either episodic or persistent high blood pressure. Untreated, a pheochromocytoma can result in severe or life-threatening damage to other body systems, especially the cardiovascular system.

Most people with a pheochromocytoma are between the ages of 20 and 50, but the tumor can develop at any age. Surgical treatment to remove a pheochromocytoma usually returns blood pressure to normal.

Source: http://www.mayoclinic.com

Symptoms

Signs and symptoms of pheochromocytomas often include:

• High blood pressure
• Heavy sweating
• Headache
• Rapid heartbeat (tachycardia)
• Tremors
• Paleness in the face (pallor)
• Shortness of breath (dyspnea)

Less common signs or symptoms may include:

• Anxiety or sense of doom
• Constipation
• Weight loss

Triggers of symptomatic spells

Spells may occur spontaneously or may be triggered by such factors as:

• Physical exertion
• Anxiety or stress
• Changes in body position
• Labor and delivery
• Surgery and anesthesia

Foods high in tyramine, a substance that affects blood pressure, also can trigger a spell. Tyramine is common in foods that are fermented, aged, pickled, cured, overripe or spoiled. These foods include:

• Some cheeses
• Some beers and wines
• Chocolate
• Dried or smoked meats

Certain medications that can trigger a symptomatic spell include:

• Monoamine oxidase inhibitors (MAOIs), such as phenelzine (Nardil), tranylcypromine (Parnate) and isocarboxazid (Marplan)
• Stimulants, such as amphetamines or cocaine

When to see a doctor

The signs and symptoms of pheochromocytoma can be caused by a number of conditions. So it's important to get a prompt diagnosis.

Although high blood pressure is a primary sign of a pheochromocytoma, most people with high blood pressure don't have an adrenal tumor. Talk to your doctor if any of the following factors are relevant to you:

• Difficulty controlling high blood pressure with current treatment plan
• A family history of pheochromocytoma
• A family history of a related genetic disorder: multiple endocrine neoplasia, type II (MEN II); von Hippel-Lindau disease; familial paraganglioma or neurofibromatosis 1 (NF1)

Source: http://www.mayoclinic.com

Causes

Researchers don't know what causes a pheochromocytoma. The tumor develops in specialized cells, called chromaffin cells, situated in the center of an adrenal gland. These cells release certain hormones, primarily adrenaline (epinephrine) and noradrenaline (norepinephrine), that help control many body functions, such as heart rate, blood pressure and blood sugar.

The role of hormones

Adrenaline and noradrenaline are hormones that trigger your body's fight-or-flight response to a perceived threat. The hormones prompt higher blood pressure, a faster heart rate and a boost in other body systems that enable you to react quickly. A pheochromocytoma results in the irregular and excessive release of these hormones.

Related tumors

While most chromaffin cells reside in the adrenal glands, small clusters of these cells are also in the heart, head, neck, bladder, back wall of the abdomen and along the spine. Tumors in these chromaffin cells, called paragangliomas, may result in the same effects on the body.

Source: http://www.mayoclinic.com

Diagnosis

Your doctor might order a number of tests.

Laboratory tests

Your doctor will likely order the following tests that measure levels of adrenaline, noradrenaline or byproducts of those hormones in your body:

• 24-hour urine test. You will be asked to collect a urine sample every time you urinate during a 24-hour period. Ask for written instructions about how to store, label and return the samples.
• Blood test. You will have blood drawn for laboratory work. Talk to your doctor about special preparations, such as fasting or skipping a medication. Don't skip a dose of medication without instructions from your doctor.

Imaging tests

If the results of laboratory tests indicate the possibility of a pheochromocytoma or paraganglioma, your doctor will order one or more imaging tests to locate a possible tumor. These tests may include:

• CT scan, a specialized X-ray technology
• MRI, which uses radio waves and a magnetic field to produce detailed images
• M-iodobenzylguanidine (MIBG) imaging, a scanning technology that can detect tiny amounts of an injected radioactive compound taken up by certain tumors
• Positron emission tomography (PET), a scanning technology that can also detect radioactive compounds taken up by a tumor

Incidental discovery

A tumor in an adrenal gland might be found during imaging studies conducted for other reasons. In such cases, your doctor would order additional tests to determine the nature of the tumor.

Genetic testing

Your doctor might recommend genetic tests to determine if a pheochromocytoma is related to an inherited disorder. Information about possible genetic factors can be important for a number of reasons:

• Because some inherited disorders can cause multiple conditions, test results may indicate the need to screen for other medical problems.
• Because some disorders are more likely to be recurrent or cancerous (malignant), your test results may affect treatment decisions or long-term plans to monitor your health.
• Results from your tests may indicate that other family members should be screened for pheochromocytoma or related conditions.

Ask your doctor about genetic counseling services that can help you understand the benefits and implications of genetic testing.

Source: http://www.mayoclinic.com

Complications

High blood pressure can damage multiple organs, particularly tissues of the cardiovascular system, brain and kidneys. Untreated, high blood pressure associated with pheochromocytomas can result in a number of critical conditions, including:

• Heart disease
• Stroke
• Kidney failure
• Acute respiratory distress
• Damage to the nerves of the eye

Cancerous (malignant) tumors

Rarely, a pheochromocytoma is cancerous (malignant), and the cancerous cells spread to other parts of the body (metastasize). Cancerous cells from a pheochromocytoma or paraganglioma most often migrate to the lymph system, bones, liver or lungs.

Risk factors

People with rare inherited disorders have an increased risk of developing a pheochromocytoma or paraganglioma, and tumors associated with these disorders are more likely to be cancerous. These genetic conditions include the following:

• Multiple endocrine neoplasia, type II (MEN II) is a disorder resulting in tumors in more than one part of the body's hormone-producing (endocrine) system. Other tumors associated with MEN II can appear on the thyroid, parathyroid, lips, tongue and gastrointestinal tract.
• Von Hippel-Lindau disease can result in tumors at multiple sites, including the central nervous system, endocrine system, pancreas and kidneys.
• Neurofibromatosis 1 (NF1) results in multiple tumors in the skin (neurofibromas), pigmented skin spots and tumors of the optic nerve.
• Hereditary paraganglioma syndromes are inherited disorders that result in either pheochromocytomas or paragangliomas.

Source: http://www.mayoclinic.com