In all of the familial syndromes that lead to medullary carcinomas (see Fig. 16.21), the thyroid shows marked hyperplasia of C-cells plus two or more medullary carcinomas. In types 2 and 3, the adrenals show bilateral medullary hyperplasia and multiple phaeochromocytomas. These might present clinically before or after the thyroid tumours. In type 3, the mucosal neuromas are present on the eyelids, lips, and tongue of patients, and there may be ganglioneuromatosis of the small and large intestines. These patients have thick blubbery lips, marfanoid habitus, high arched palate, and pes cavus. In all types, relatives of clinically diagnosed patients must be screened routinely for the presence of raised calcitonin and, in types 2 and 3, for raised catecholamine secretions.
