Pheochromocytoma. The great mimic.

A pheochromocytoma is a tumor of the chromaffin cells of the adrenal gland medulla that produces excessive amounts of norepinephrine. It is difficult to diagnose and complicated to treat because of its variable symptoms and location in the body. The tumor is most likely to cause uncontrolled hypertension, nervousness, diaphoresis, and palpitations, but, at other times, may show no symptoms at all. The diagnosis is established by measuring the plasma levels of the catecholamine hormones, norepinephrine and epinephrine. Although 10% of pheochromocytomas are extra-adrenal, most appear in one adrenal gland. If a tumor can be located by radiological techniques, it can be cured by surgical removal. Since these tumors may recur, it is necessary to reevaluate the patient periodically by measuring catecholamine levels and by radiological studies. We present a case study of one patient with a malignant pheochromocytoma, outlining the diagnosis, treatment, and postadrenalectomy follow-up.