Abstract
A family with MEN2 A was reported. This family included nine cases of the thyroid cancer, in which five cases of the medullary thyroid carcinoma were diagnosed. Among five one case had the pheochromocytoma. The propositus was operated for Hirschsprung's disease in infancy and was operated for the medullary thyroid carcinoma at the age of 23. A DNA analysis of the propositus revealed a mutation at codon 618 of exon 10. Periodic biochemical tests and DNA analyses might be nesessary for this family.