Pheochromocytoma: A Rare Adrenal Tumor

Author: Botheina Ghandour PhD

Overview

Pheochromocytoma is a rare tumor that develops in your adrenal glands. The cells of this tumor

produce catecholamines, which are hormones that stimulate the fight or flight response. Most

often, the tumor is benign (Cleveland Clinic, 2022). However, in rare instances, the tumor can

become malignant. Symptoms of this condition vary widely. Some may exhibit high blood

pressure or increased heart rate, while others exhibit no symptoms at all (Cleveland Clinic,

2022). Pheochromocytoma is challenging to diagnose due to its rarity and asymptomatic nature.

Cause/Research

The exact cause of pheochromocytoma is not fully understood. It is known that the tumor forms

in chromaffin cells. These cells are located in the adrenal medulla and produce hormones like

adrenaline and norepinephrine. Under normal conditions, these hormones are released to

stimulate the fight or flight response when the body senses a threat. The response results in

higher blood pressure, heart rate, and blood sugar levels. The tumor will cause these cells to

release hormones excessively.

Current research suggests that genetics could play a role in pheochromocytoma. Mutations in

genes RET, VHL, NF1, and SDH can alter cellular pathways and may predispose some to

pheochromocytoma (Fishbein et al., 2017; Jhawar et al., 2022). Among these genes, mutations to

the RET gene are especially important. RET is a proto-oncogene that promotes cell growth. A

mutation to RET causes Multiple Endocrine Neoplasia type 2 (MEN2). This is a syndrome

where multiple endocrine glands exhibit abnormal growth or tumors in the glands. MEN2A is a

form of MEN2 in which patients usually develop thyroid cancer, but some cases show

pheochromocytoma to develop alongside thyroid cancer (Krampitz et al., 2014).

RET is then maybe associated with a greater risk of developing pheochromocytoma. So far, the

current research has shown that genetics may increase the risk of developing pheochromocytoma

or developing a syndrome that can result in pheochromocytoma. This reality highlights the need

for increased funding efforts to establish a cause and ultimately enhance treatment options for

this condition.

Diagnosis/Treatment

Pheochromocytoma’s asymptomatic nature makes it difficult to diagnose. Then, familial history

and tests become essential to reach a diagnosis. Healthcare providers may ask patients if their

family members have had this condition. A urine test and catecholamine blood test can be used

to see if the patient has higher-than-normal catecholamine levels (Cleveland Clinic, 2022). This

could be a sign of pheochromocytoma. Imaging of the adrenal gland through a CT scan or MRI

can be used to see if any abnormal growth is taking place (Cleveland Clinic, 2022). Difficulty

diagnosing this disease again highlights the need for further research. If studies reveal a strong

genetic basis for this disease, genetic testing may become a useful tool for physicians (Cleveland

Clinic, 2022).

Treatment is dependent upon many factors, such as the size of the tumor and malignancy.

Generally, surgery is the best option if feasible. Radiation therapy and chemotherapy can be used

to stop the overgrowth of cancer cells (Cleveland Clinic, 2022). In the future, more targeted

therapy options could be utilized. But this would require more research to identify targets. Again,

further research efforts would provide physicians with more tools to treat this rare

disease.

Key Takeaways

Generally, pheochromocytoma is a rare benign tumor that presents asymptomatically. However,

in some cases, this tumor can become cancerous. Its rarity, presentation, and unknown cause

riddle diagnostic procedures with difficulty. Current research suggests that there may be some

genetic link. Nevertheless, more studies need to be conducted to pinpoint causative agents. This

would improve a physician's diagnostic ability while also affording them better targeted

treatment options.

Sources

Cleveland Clinic. (2022, June 30). Pheochromocytoma. Cleveland Clinic.

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Lichtenberg, T. M., Murray, B. A., Ghayee, H. K., Else, T., Ling, S., Jefferys, S. R., de Cubas, A.

A., Wenz, B., Korpershoek, E., Amelio, A. L., Makowski, L., Rathmell, W. K.,

Gimenez-Roqueplo, A. P., Giordano, T. J., ... Wilkerson, M. D. (2017). Comprehensive

Molecular Characterization of Pheochromocytoma and Paraganglioma. Cancer cell, 31(2),

181–193. https://doi.org/10.1016/j.ccell.2017.01.001

Jhawar, S., Arakawa, Y., Kumar, S., Varghese, D., Kim, Y. S., Roper, N., Elloumi, F., Pommier,

Y., Pacak, K., & Del Rivero, J. (2022). New Insights on the Genetics of Pheochromocytoma and

Paraganglioma and Its Clinical Implications. Cancers, 14(3), 594.

https://doi.org/10.3390/cancers14030594

Krampitz, G. W., & Norton, J. A. (2014). RET gene mutations (genotype and phenotype) of

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