IN 1961, Sipple1 reported an increased incidence of carcinoma of the thyroid in patients with pheochromocytoma and noted that this association was 14 times greater than in the general population. However, it was apparently not appreciated by Sipple that the carcinoma was of the medullary type. In 1962, it was reported that parathyroid adenomas also occur with some degree of frequency in this syndrome. Williams2 reviewed the pathologic characteristics of the thyroid carcinomas and found that they were all of the medullary variety. Since then, Sipple's syndrome has been recognized as a form of multiple endocrine adenopathy, and in the last few years, other features, eg, familial incidence, carcinoid syndrome, mucosal neuromas, marfanoid habitus, megacolon, and Cushing's syndrome, have all been reported.
We report a new variant of Sipple's syndrome in which the patient had a pheochromocytoma, hypercalcitoninemia, and C-cell hyperplasia. We believe this to be the first