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.
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
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.
- 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.
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.