[Incidence of medullary thyroid gland carcinoma in unilateral and bilateral pheochromocytoma].

In the autopsy material of the Departments of Pathology in Zürich and Winterthur the frequency of cases with unilateral or bilateral pheochromocytoma and combinations of pheochromocytoma with additional medullary thyroid carcinoma with amyloid has been studied. 56 cases (0.084 percent) of pheochromocytoma, 50 unilateral and 6 bilateral, were found in a material of 66782 autopsies. Three of the 6 patients with bilateral pheochromocytomas had an additional medullary thyroid carcinoma with amyloid deposits, while no patient with unilateral pheochromocytoma exhibited this type of thyroid tumor. In families with Sipple's syndrome, however, combinations of unilateral pheochromocytoma with medullary thyroid carcinoma do occur. No typical coincidence of pheochromocytoma with other malignant tumors could be demonstrated in our material, although this possibility is discussed in the literature.