Pheochromocytoma

A pheochromocytoma (pronounced FEE-oh-KROH-moh-sy-TOH-muh) is a rare tumor that forms in the center of one or both of your adrenal glands (adrenal medulla). The tumor is made of a certain type of cell called a chromaffin cell, which produce and release the hormones that cause the “fight or flight” response.

Usually, pheochromocytoma affects only one adrenal gland, but it can affect both glands. Sometimes there’s more than one tumor in one adrenal gland.

Most pheochromocytomas are benign (not cancerous). Approximately 10% to 15% of pheochromocytomas may be malignant (cancerous). There’s no standard staging system for pheochromocytoma if it’s cancerous. Instead, it’s described as the following:

• Localized pheochromocytoma: The tumor is in one or both adrenal glands only.
• Regional pheochromocytoma: The cancer has spread to lymph nodes or other tissues near your adrenal glands.
• Metastatic pheochromocytoma: The cancer has spread to other parts of your body, like your liver, lungs, bone or distant lymph nodes.
• Recurrent pheochromocytoma: The cancer has recurred (come back) after it has been treated. It may come back in the same place or in another part of your body.

What are adrenal glands?

You have two adrenal glands, one on top of each kidney in the back of your upper abdomen. They are part of your endocrine system. Each adrenal gland has two parts. The outer layer of your adrenal gland is called your adrenal cortex. The center of your adrenal gland is called your adrenal medulla.

Your adrenal medullae make hormones called catecholamines that help regulate the following important bodily functions and aspects:

• Heart rate.
• Blood pressure.
• Blood sugar (blood glucose).
• The way your body responds to stress (the “fight or flight” response).

The primary catecholamines include:

• Dopamine.
• Epinephrine (adrenaline).
• Norepinephrine (noradrenaline).

Sometimes a pheochromocytoma can release extra adrenaline and noradrenaline into your blood, causing certain symptoms.

What is the difference between pheochromocytoma and paraganglioma?

Pheochromocytoma and paraganglioma are both rare tumors that come from the same type of cells known as chromaffin cells.

Pheochromocytoma is a tumor that forms in the center of your adrenal gland (adrenal medulla), and paragangliomas form outside your adrenal gland.

Who gets a pheochromocytoma?

Anyone at any age can get a pheochromocytoma, but they occur most often in people between 30 and 50 years of age. Approximately 10% of cases occur in children.

How common are pheochromocytomas?

Pheochromocytomas are rare tumors. The true number of pheochromocytoma cases is unknown since many people with pheochromocytomas don’t have symptoms and go undiagnosed. Less than 1% of people who have high blood pressure have a pheochromocytoma.