Pheo, Adrenal Gland Tumor, Pheochromocytosis
Pheochromocytoma is a tumor made up of adrenal gland cells. Normally, adrenal gland cells secrete epinephrine and norephinephrine, which are active in the regulation of heart rate and blood pressure. Pheochromocytoma cells secrete excessive amounts of the hormones epinephrine and norepinephrine, resulting in periods of very high blood pressure.
Most pheochromocytoma are benign (noncancerous) and about 10% are malignant (cancerous). Most pheochromocytoma grow on the adrenal glands, which are themselves perched on top of the kidneys. About 10% of all pheochromocytoma occur elsewhere in the body.
The cause of pheochromocytoma is not yet known. Scientists suspect a genetic link.
Factors associated with pheochromocytoma include:
- Age: 30-60 years
- A family history of pheochromocytoma, tumors in other glands of the body, or other hormonal disorders
- High manganese diets
- Deficiencies of iron or copper
- Genetic diseases including:
- Von Hippel-Lindau disease
- Multiple endocrine neoplasia, type 2
- Neurofibromatosis type 1
Symptoms may occur many times during the day or as infrequently as once every few months. Symptoms may be brought on by pressure on the tumor (as might occur accidentally during a massage), medications (such as certain anesthetics and beta-blockers), intense emotion. Symptoms can include:
- Severe headaches
- Excessive sweating
- Fast heart rate (tachycardia)
- Sensation of a panic attack
- Vision changes
- 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
- High blood pressure
- Tingling, burning, numbness in the legs and feet
- Dilated pupils
- Vision changes
Your doctor will take a medical history and perform a physical exam. Diagnosis of pheochromocytoma may include the following tests:
- 24-Hour Urine Testing–to measure amounts of catecholamines (a group of hormones produced 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
- CAT Scan–a type of x-ray that uses a computer to make pictures of structures inside the body. The CT scan can be 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–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
- Biopsy–the surgical removal of a small piece of the tumor for examination
If pheochromocytoma is benign (not cancerous), then the tumor is surgically removed. Sometimes, the adrenal glands are removed as a part of this process. Prior to surgical removal, the high blood pressure will need to be brought under control, using first the medication phenoxybenzamine, followed by beta-blocking antihypertensive agents.
Laparoscopic adrenalectomy is the surgical removal of the adrenal glands. It involves making three or four small incisions in the abdomen and inserting a special camera through the incisions so that the surgeon can see the tumor area.
If pheochromocytoma is cancerous, the following treatment options may be used:
Surgery is used to remove the affected body tissue.
Drugs are used to kill the cancer cells.
High doses of radiation are used to shrink cancer cells.
Since little is known about the causes of pheochromocytoma, prevention methods are not available.