Pheochromocytoma

What is pheochromocytoma?

A pheochromocytoma is a tumor that forms in the adrenal medulla (a hormone-secreting gland located above each kidney) and causes endocrine hypertension or hormonally induced high blood pressure.

The tumor's excessive secretion of epinephrine and norepinephrine (catecholamines) causes hypertension and increased cardiac output, putting a severe strain on the heart. Although approximately 90% occur in the adrenal medulla, they can also occur along the carotid artery (carotid bodies), aorta, or in the wall of the urinary bladder. Although most pheochromocytomas are noncancerous or benign, their excessive hormone production may cause irreparable cardiovascular damage, even death, if not diagnosed and treated.

Thirteen percent of pheochromocytomas are malignant, as determined by tumor spread. Pheochromocytomas most often occur in young adults, and there is some evidence of genetic component. They have also been associated with various neurologic disorders and with medullary carcinoma of the thyroid.

How is it diagnosed?

History: The most common presenting symptom is sustained or intermittent high blood pressure. Other symptoms include severe headaches, excessive sweating, anxiety, visual disturbances, rapid heart rate, palpitations, or decreased blood pressure with changes in position (orthostatic hypotension).

Physical exam: Elevated blood pressure (hypertension), rapid heart rate, and orthostatic hypotension may be noted during a physical examination.

Tests: Diagnosis depends upon the individual's symptoms and the results of highly specific chemical and pharmacologic tests. Blood glucose levels may be elevated.

How is pheochromocytoma treated?

Pheochromocytomas, in accessible areas, are surgically removed. Otherwise, individuals receive medication (chemotherapy). Before surgery, the individual is given medication to treat the high blood pressure and block the effects of the catecholamines.

Medications

Tenormin (Atenolol), Cardura (Doxazosin)

What might complicate it?

Potential complications associated with the development of a pheochromocytoma include severe hypertension, heart problems, cardiac arrest, and diabetes.

Predicted outcome

Typically, individuals with tumors that can be surgically removed recover completely. The five-year survival for individuals with malignant pheochromocytomas is between 35% and 60%.

Alternatives

Differential diagnoses include hypertension (both essential and of renal origin) and thyrotoxicosis.

Appropriate specialists

Endocrinologist and general surgeon.

Last updated 21 June 2015