Pheochromocytoma

Medical Author:
Medical Editor:

Pheochromocytoma facts

  • Pheochromocytoma is a relatively rare tumor of the adrenal glands or of similar specialized cells outside of the adrenal glands.
  • Pheochromocytomas secrete catecholamine hormones (adrenaline and related hormones) that are responsible for the characteristic symptoms.
  • Headache, sweating, and a fast heartbeat are typical symptoms, usually in association with markedly high blood pressure.
  • About 10% of pheochromocytomas are malignant.
  • Surgery is the treatment of choice.
  • Pheochromocytomas can occur in combination with other tumors, conditions and in some familial (inherited) syndromes.

What is a pheochromocytoma?

Pheochromocytomas are a type of tumor of the adrenal glands that can release high levels of epinephrine and norepinephrine. As the name implies, the “ad-renal” glands are located near the "renal" (kidney) area. In other words, the adrenal glands are small glands that are located near the top of the kidneys. One adrenal gland sits on top of each of the two kidneys.

Despite their small size, the adrenal glands have many functions. They are complex endocrine (hormone secreting) glands. Cells in different regions of the adrenal glands have different functions in the endocrine system. There is an area (zona fasciculata) where the cells secrete cortisol, a hormone similar to cortisone. There is another area (zona glomerulosa) where cells secrete a hormone called aldosterone which helps in water regulation.

There is yet another area, referred to as the adrenal medulla, where the cells secrete substances called catecholamines -- epinephrine, norepinephrine and dopamine. These are "flight or fight" hormones. They are responsible in part for that feeling of an "adrenaline" rush people feel when they are afraid. It is these cells that are involved in a pheochromocytoma. Basically, a pheochromocytoma is a tumor of these catecholamine-secreting cells, and that causes the clinical signs and symptoms we will discuss below. The catecholamine-secreting cells are sometimes referred to as chromaffin cells, and they are found in other areas of the body as well as in the adrenal medulla.

Sometimes, pheochromocytomas arise from chromaffin cells that are located outside of the adrenal gland. In this case, they are termed extra-adrenal pheochromocytomas or paragangliomas and are usually located in the abdomen.

Pheochromocytomas may occur in persons of any age. The peak incidence is between the third and the fifth decades of life. Pheochromocytomas are, fortunately, quite rare (2 to 8 people per million per year), and the majority of them are entirely benign.

Picture of the endocrine system
Picture of the endocrine system
Medically Reviewed by a Doctor on 12/16/2013

Patient Comments

Viewers share their comments

Pheochromocytoma - Experience Question: Please describe your experience with pheochromocytoma.
Pheochromocytoma - Symptoms and Signs Question: What symptoms and signs did you experience with your pheochromocytoma?

Pheochromocytoma Tumor Symptoms

What Are the Symptoms of Pheochromocytoma?

Someone with a pheochromocytoma usually has three classic symptoms, headache, sweating, and heart palpitations (a fast heart beat) in association with markedly elevated blood pressure (hypertension). Other conditions that may accompany these classic symptoms are as follows:

  • anxiety,
  • nausea,
  • tremors,
  • weakness,
  • abdominal pain, and
  • weight loss.

Some people, however, never develop symptoms of a pheochromocytoma. Up to 10% of cases are discovered incidentally, meaning that they are not suspected and only found when the patient is undergoing diagnostic studies for other conditions.