What Is Pheochromocytoma?
Pheochromocytoma is a rare type of tumor that usually develops in the inner portion (medulla) of the adrenals, the small glands atop each kidney. The tumor causes excess release of epinephrine (adrenaline) and norepinephrine (noradrenaline), hormones that help to regulate heart rate and blood pressure.
The primary effect of the tumor is to cause intermittent or sustained periods of high blood pressure. Sporadic surges in blood pressure are marked by a rapid or pounding heartbeat, palpitations, headache, sweating, and extreme anxiety. Symptomatic attacks are sometimes brought on by emotional upset, a change in posture, or certain medications and tend to increase in frequency, duration, and severity if the tumor is left untreated. Treatment should be initiated as early as possible to prevent the long-term consequences of high blood pressure, which include heart disease, stroke, and kidney damage. (In patients with sustained high blood pressure, hypertension may persist even after removal of the tumor.)
Pheochromocytomas are most common in young to middle-aged adults. Most cases are benign (noncancerous) and affect only one adrenal gland. Sometimes tumors arise on both adrenals (especially in people with familial pheochromocytoma) or at other sites in the abdomen or chest. About 20 to 25 percent of pheochromocytomas are malignant (cancerous) and may spread to distant sites. Tumors that have spread are difficult to treat with surgery or chemotherapy. Benign tumors, on the other hand, are usually curable with surgery.
What Causes Pheochromocytoma?
- The cause of pheochromocytomas is unknown.
- Pheochromocytoma may be inherited.
- Individuals who have hereditary diseases such as multiple endocrine neoplasia type 2, neurofibromatosis type 1, paraganglioma syndromes or Von Hippel-Lindau disease are at risk for pheochromocytoma.
- Some people with a rare inherited syndrome called multiple endocrine neoplasia develop pheochromocytomas in association with medullary thyroid tumors and overproduction of parathyroid hormone (hyperparathyroidism).
Symptoms of Pheochromocytoma
- Headache, often severe
- Palpitations, or rapid or pounding heartbeat
- Involuntary trembling
- High blood pressure
- Flushing or feeling hot
- Excessive sweating
- Lightheadedness, especially when arising from a sitting position
- Chest or abdominal pain
- Tingling, burning, numbness in the legs and feet
- Weight loss
- Nervousness, irritability, or anxiety
- Mental confusion or psychosis
- Clammy skin
- Blurry vision
- Increased appetite
- Muscle weakness
- Sensation of a panic attack
- Intolerant to high temperature
- Shortness of breath
There is no known way to prevent pheochromocytoma.
- Blood and urine samples are taken to check for high levels of epinephrine, norepinephrine, and their breakdown products. Blood tests may show a high blood glucose level.
- A CT (computed tomography) scan or MRI (magnetic resonance imaging) of the abdomen usually identifies an adrenal tumor.
- A radioisotope scan shows the image of the functioning adrenal gland.
- A clonidine suppression test evaluates blood levels of norepinephrine.
- An ultrasound detects adrenal tumors.
- A fluorodopamine PET scan may be performed when the blood tests show presence of pheochromocytoma, but other imaging tests do not reveal the presence of the tumor.
- In rare cases, an octreotide (hormone) or MIBG scan is used to visualize the tumor.
How to Treat Pheochromocytoma
- Surgical removal of the tumor (adrenalectomy) is possible in most cases and usually leads to a cure and full recovery. The earlier the tumor is treated the better. Surrounding tissue may be removed as well if there is concern that the tumor may have spread locally. Drugs are given to control blood pressure for several weeks prior to the operation.
- If a malignant tumor has spread to other sites, radiation or chemotherapy may be tried, although results are generally disappointing.
- In a small percentage of cases, recurrence of tumors after surgery requires additional surgery.
- Drugs to lower blood pressure are used when hypertension persists after removal of a benign pheochromocytoma or in cases of malignant tumors.
When to Call a Doctor
See a doctor if you develop symptoms of pheochromocytoma.
Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference
Simeon Margolis, M.D., Ph.D., Medical Editor
Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50
Updated by Remedy Health Media