Pheochromocytoma, the chromaffin cell tumor of the adrenal medulla, should be considered in all cases of hypertension. The result of its removal, before irreversible cardiovascular damage is caused, is dramatic and life-saving. Emphasis must be placed on the clinical diagnosis, for up to the present it has been diagnosed principally post mortem. Smithwick and others1 emphasize that the symptoms, signs and diagnostic phenomena are recognizable by physicians. In practically every case of pheochromocytoma at least three or four of the important observations may be present. It is believed that if the data were obtained regularly in hypertensive patients diagnosis of the condition would seldom be overlooked.
Paroxysmal attacks of hypertension are characteristic. However, it is important to realize that these are not present in more than 30 per cent of patients and that some are said to have them in the absence of pheochromocytoma. Characteristic paroxysms last minutes to