Pheochromocytoma; clinical aspects and surgical results.

PHEOCHROMOCYTOMA, while relatively uncommon, is the most frequently encountered surgical lesion known to arise from the medulla of the adrenal glands. Although this tumor may be nonfunctioning and cause no alteration in blood pressure, usually it liberates pressor substances which produce either paroxysmal or sustained hypertension or a combination of the two. This tumor is not a common cause of hypertension, but if the diagnosis is made relatively early during the course of the tumor, complete relief may be anticipated after surgical removal in virtually all cases. The present study, which is based on a group of 25 patients seen between January, 1944, and February, 1952, each of whom had pheochromocytoma, was undertaken primarily to evaluate results after surgical removal of tumors of this type. Unfortunately, the diagnosis of pheochromocytoma is not easy, and some patients may harbor this type of tumor for many years before it is recognized. Because