Malignant pheochromocytoma lacking clinical features of catecholamine excess until the late stage

A malignant pheochromocytoma is described in a 71-year-old man. Osseous met astases became manifest 12 years after successful removal of the primary tu mor which originated in paraganglionic tissue near the right adrenal gland. Although the patient had no symptoms of catecholamine excess initially, hy pertension, tachycardia and excessive sweating appeared several months befo re his death, concomitantly with a sharp increase in noradrenaline secretio n due to an accelerated growth of metastatic tumors, Since there is no hist ologic criterion of malignancy in this neoplasm, it would be prudent to con sider every case of pheochromocytoma as potentially malignant and to follow up carefully for a long time after removal of the primary tumor.