Causes and Risk Factors of Pheochromocytomas

Researchers aren't certain what specific causes lead to the growth of pheochromocytomas.

However, more than 20 genes have been discovered that are linked to the development of pheochromocytomas. Yet in cases that are not genetic, no known environmental or lifestyle factors have been associated with pheochromocytomas.

The presence of pheochromocytoma in an adrenal gland can cause problems as a result of tumor-producing epinephrine and other compounds similar to epinephrine.

As a subsequent risk factor, when too much epinephrine is in your body, you can experience episodes in which your blood pressure is elevated and your heart rate becomes too fast. You may also feel sweaty or dizzy during these episodes.

This article will discuss the potential causes and known genetic conditions associated with the growth of pheochromocytomas.

Common Causes

The exact cause of pheochromocytomas is unknown. Most pheochromocytomas spontaneously develop in the adrenal glands without a clear reason. Researchers estimate that about 60% of cases are random, with up to 40% of the remaining cases linked to hereditary factors.

Genetics

Around 25% of pheochromocytomas are linked to the following three genetic conditions:

• Multiple endocrine neoplasia disorder: The RET gene that causes this thyroid gland condition may also trigger pheochromocytomas.
• Type 1 neurofibromatosis: Originated from a mutation of NF1 gene, this hereditary condition causes tumors to grow around nerves and may be a cause of pheochromocytoma as well.
• Von Hippel-Lindau disease: A mutation of VHL gene causes tumors to grow throughout the body, including in the adrenal glands. 

Other genetic conditions and genes linked to pheochromocytomas include:

• Carney-Stratakis dyad: A rare inherited disorder that causes tumors in the gastrointestinal (GI) tract
• Hereditary paraganglioma-pheochromocytoma syndrome: A hereditary condition causing the growth of benign tumors in tissue near the adrenal glands
• SDHA, SDHB, SDHC, and SDHD genes (succinate dehydrogenase genes)
• THEM127 gene
• MAX gene

Cases of pheochromocytomas caused by genetics tend to occur in people younger than age 30 and are more likely to be bilateral, meaning they occur in both adrenal glands. Some of these tumors are also more likely to be cancerous than tumors that occur randomly.

Due to the high incidence of hereditary mutations associated with the tumor, some physicians recommend genetic testing for everyone who develops a pheochromocytoma. This is especially important when the tumor occurs in young people.

A Word From Verywell

Pheochromocytomas are rare tumors, but fortunately, they do have a good prognosis with treatment. If you or a loved one is diagnosed with a pheochromocytoma, you can be assured that there's nothing you could have done to avoid the condition.

If you are suspected of having a genetic mutation that causes pheochromocytoma, your healthcare team will likely refer you to a genetic counselor. He or she will be able to offer guidance in family planning and answer any questions you may have about your family history and hereditary gene line.