Clinically unsuspected pheochromocytomas. Experience at Henry Ford Hospital and a review of the literature.

Thirty-two histopathologically confirmed pheochromocytomas were diagnosed at Henry Ford Hospital, Detroit, between 1951 and 1982. Eleven (34%) of these cases were clinically unsuspected exhibiting none of the typical symptoms of palpitation, diaphoresis, or headache, and only five were hypertensive. These pheochromocytomas may be discovered during computed tomography of the abdomen while evaluating multiple endocrine neoplasia, abdominal pain, and abdominal masses, or they may present at autopsy, at surgery, or as a mass lesion without paroxysmal symptoms or hypertension. Before 1962, 53% of these tumors were undiagnosed before surgery or autopsy; however, since 1962 only 18% of pheochromocytomas have remained clinically unsuspected. By maintaining a higher index of suspicion and using newer biochemical and imaging techniques, the incidence of clinically unsuspected pheochromocytomas should be reduced.