For Healthcare Professionals

What Are Pheochromocytoma and Paraganglioma?

Pheochromocytomas are rare tumors originating from the chromaffin cells in the medulla of the adrenal glands.

Closely related and even less common are paragangliomas, which derive from the extra-adrenal parasympathetic or sympathetic nervous system. Paragangliomas are most often located in the head and neck region, chest, abdomen, or pelvis. Paragangliomas usually have a poorer prognosis and higher malignant potential than pheochromocytomas.

The clinical manifestations of these conditions are induced by the release of excessive amounts of catecholamines (eg, metanephrine, norepinephrine, noradrenaline, epinephrine, adrenaline, or dopamine) by these neuroendocrine tumors. Most pheochromocytomas are benign, and if diagnosed and treated properly, 90% of cases are curable by surgical resection.