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Pheochromocytoma and Paraganglioma - Overview

Pheochromocytoma and Paraganglioma - Overview

12/30/2013 06:15 PM EST

Source: National Institute of Child Health and Human Development
Related MedlinePlus Page: Pheochromocytoma



Overview

Pheochromocytoma

Pheochromocytoma is a rare endocrine tumor originating in the adrenal glands, specifically, the medulla of adrenal glands. The adrenal glands are two small glands that sit on top of the kidneys and produce hormones called catecholamines. Catecholamines include metanephrine, norepinephrine (noradrenaline), epinephrine (adrenaline), and dopamine. These hormones help regulate your responses to stress, heart rate, and blood pressure. Once your body encounters any stress, your adrenal glands secrete these hormones into your bloodstream which in turn affects the functions of other organs and tissues in your body.  In patients with pheochromocytoma there is a release of excessive amounts of these hormones, which can potentially increase your heart rate and blood pressure. Having pheochromocytoma may become life threatening when the tumor goes unrecognized or untreated.
Distant metastatic sites include bone, lung, lymph nodes, and liver.
3D illustration of kidneys and adrenal glands
Click image to view larger.
The adrenal glands are two small glands that sit on top of the kidneys and produce hormones that regulate stress responses organ functions and many metabolic processes.

Paraganglioma

Paraganglioma is a tumor that is closely related to pheochromocytoma and originates from outside the adrenal glands, specifically from the sympathetic or parasympathetic nervous system. The sympathetic nervous system controls most of the body's function during action or while under stress. The parasympathetic nervous system regulates the body's function at rest. When such tumors arise outside the adrenal gland, they are referred to as "extra-adrenal." Extra-adrenal paragangliomas derived from the sympathetic nervous system almost always produce catecholamines and often lead to hypertension or high blood pressure; however, paragangliomas of the parasympathetic tissue, found mainly in the head and neck, rarely produce significant amounts of catecholamines and do not usually cause hypertension. Paragangliomas are much less common than pheochromocytomas. Just like pheochromocytoma, paraganglioma-related signs and symptoms are also caused by the presence of excess amounts of catecholamines. Paragangliomas are most often located in the head and neck region, heart, bladder, spine, chest, abdomen, or pelvis.

Who Should Be Examined for Pheochromocytoma?

  • Patients with very difficult-to-control hypertension
  • Patients requiring more than 4 blood pressure medications
  • Patients with onset of hypertension before the age of 35
  • Patients with signs or symptoms of pheochromocytoma
  • Patients with a strong family history of pheochromocyoma

Mortality/Morbidity

Although pheochromocytomas are rare, making the diagnosis is critical because the malignancy rate is 10%.
Pheochromocytomas can lead to:
  • Cardiovascular problems: Cardiac arrhythmias, heart disease, myocarditis, signs and symptoms of myocardial infarction, dilated cardiomyopathy, and pulmonary edema, either of cardiac or noncardiac origin.
  • Other problems: seizures, stroke and intracerebral hemorrhage also may occur because of uncontrolled hypertension.

Race

Pheochromocytomas are diagnosed in people of all races, but are less common in African Americans.

Sex

Pheochromocytomas occur equally in both males and females.

Age

Pheochromocytomas can occur at any age, although the most frequent age is between 30 and 50s.

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