Definition

Pheochromocytoma is a tumor. It is made up of special adrenal gland cells. These cells secrete hormones such as epinephrine and norepinephrine. These hormones help to regulate the heart rate and blood pressure. The cells may secrete excessive amounts of the hormones. This results in periods of:

• Very high blood pressure
• Rapid heart beats or palpitations
• Excess sweating
• Severe headaches

Most of these tumors are benign (noncancerous). About 10% are malignant (cancerous). Most of the tumors grow on the adrenal glands. The glands are on top of the kidneys. About 10%-20% the tumors occur elsewhere in the body.

Adrenal Glands

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Causes

The cause is not yet known. Scientists suspect a genetic link.

Risk Factors

Factors associated with pheochromocytoma include:

• A family history of pheochromocytoma, tumors in other glands of the body, or other hormonal disorders
• Genetic diseases including:
  • Von Hippel-Lindau disease
  • Multiple endocrine neoplasia, type 2
  • Neurofibromatosis type 1
  • Paraganglioma syndromes

Symptoms

Up to 50% of patients have no symptoms. This tumor is found during the investigation of some other unrelated illness.

Symptoms may occur many times during the day. They can also occur as infrequently as once every few months. Symptoms may be brought on by pressure on the tumor (during a massage), medications (such as certain anesthetics and beta-blockers), or intense emotion. Symptoms can include:

• Severe headaches
• Excessive sweating
• Fast heart rate ( tachycardia )
• Sensation of a panic attack
• Vision changes (blurred vision)
• Nausea, vomiting, constipation
• Pounding heart beat (palpitations)
• Chest pain
• Involuntary trembling (tremor)
• Pain in the lower chest or upper abdomen
• Warmth, flushing
• Increased appetite
• Weight loss
• Insomnia
• High blood pressure (either sporadic or constant)
• Tingling, burning, or numbness in the legs and feet
• Shortness of breath
• Muscle weakness
• Anxiety
• Intolerant to high temperature

Diagnosis

Your doctor will take a medical history. A physical exam will be done. Diagnosis of pheochromocytoma may include the following tests:

• 24-hour urine testing—to measure amounts of catecholamines (a group of hormones made by the adrenal glands near the kidneys), including epinephrine and norepinephrine and their byproducts (metanephrines)
• Blood testing—to measure catecholamines and metanephrines
• Clonidine suppression test—a dose of the drug clonidine is given, and blood levels of norepinephrine are tested
• CT scan —a type of x-ray that uses a computer to make pictures of structures inside the body; used to diagnose the presence of the tumor
• Ultrasound —a noninvasive test using sound waves, which may be used to help detect adrenal tumors
• MRI scan —a test that uses magnetic waves to produce cross-sectional or three-dimensional images of the body’s tissues
• MIBG scintiscan (or adrenal medullary imaging)—an imaging test for diagnosing adrenal tumors, in which tiny amounts of radioactive materials are injected into the body
• Fluorodopamine PET scan—used when the blood tests indicate presence of pheochromocytoma, but other imaging tests do not reveal the presence of the tumor

Treatment

This may be used if the tumor is cancerous and has spread outside of the adrenal glands. It involves the use of:

• Docarbazine
• Vincristine
• Cyclophosphamide

Radiation may also be used. It is used to destroy blood vessels that may be feeding the tumor. This process is called ablation.

Prevention

There are no known prevention methods.