Results of a screening program for multiple endocrine neoplasia type 2A: a clinical study of a Japanese family.

A Japanese family of 87 members in five generations with multiple endocrine neoplasia type 2A (MEN 2A) is described regarding the utility of screening tests for early detection of medullary thyroid carcinoma and the potential for DNA diagnosis of MEN 2A gene carriers. The screening programs for family members in this series include measurements of plasma calcitonin concentrations after intravenous injection of pentagastrin (0.5 micrograms/kg/5 sec) and 24-hour urinary excretion of catecholamines. While 18 MEN 2A patients had been previously diagnosed, these screening programs revealed five additional patients with MEN 2A (aged 16, 19, 35, 37, and 57). Prediction of MEN 2A gene carriers by DNA analysis has been attempted but is not yet possible in this family.