Pheochromocytoma is a type of neuroendocrine tumor (from chromaffin cells in adrenal glands) that results in the irregular secretion of epinephrine and norepinephrine. Symptoms include hypertension, palpitations, and headaches. Most pheochromocytomas are benign; malignant pheochromocytomas are rare.
Beta blockers and/or antihypertensive medications reduce symptoms. Another common treatment is surgery (tumor and/or adrenal gland removal).
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References
Jameson, J. Larry, et al. Harrison's Principles of Internal Medicine, 20th Ed. New York: McGraw-Hill Education, 2018.