Clinical Screening as Compared with DNA Analysis in Families with Multiple Endocrine Neoplasia Type 2A

Multiple endocrine neoplasia type 2A (MEN-2A) is an inherited disease characterized by medullary thyroid carcinoma, pheochromocytoma, and parathyroid adenoma 1 , 2 . MEN type 2B (MEN-2B) is characterized by medullary thyroid carcinoma, pheochromocytoma, mucosal ganglioneuroma, and a marfanoid habitus 3 , 4 . In familial medullary thyroid carcinoma, medullary thyroid carcinoma occurs without the other abnormalities 5 – 7 . The pattern of inheritance of all these syndromes is autosomal dominant, with a high degree of penetrance and variable expression. Medullary thyroid carcinoma originates in calcitonin-producing cells (C cells) of the thyroid gland 8 . Patients with this condition or its precursor, C-cell hyperplasia, have supranormal . . .