Multiple endocrine neoplasia type 2A is a hereditary syndrome characterized by medullary thyroid carcinoma, pheochromocytoma and primary hyperparathyroidism. It is characterized by a high concentration of serum calcitonin. Recent genetic studies have ...
Multiple endocrine neoplasia type 2A is a hereditary syndrome characterized by medullary thyroid carcinoma, pheochromocytoma and primary hyperparathyroidism. It is characterized by a high concentration of serum calcitonin. Recent genetic studies have identified the presence of germline missense mutations in the RET proto-oncogene in almost 100% of MEN-2 patients. We report a patient (19-year old man) of MEN-2A family with point mutation at codon 634 of the RET proto-oncogene. He presented both thyroid nodules, and laboratory examination of blood revealed elevated serum calcitonin. Although ultrasonography, CT and FNAC had shown no evidence of malignancy, the patient had underwent total thyroidectomy and central neck dissection prophylactically. The result of pathologic finding was medullary thyroid cancer without LN metastasis. We identified a point mutation of TGC (Cys) to TAC (Tyr) at codon 634 of exon 11 at RET proto-oncogene in 5 cases from the patient and his family by DNA sequencing test.