Hereditary thyroid cancer        CHEN Xi，LI Hong-wei. Department of Surgery, Ruijin Hospital of Shanghai Jiaotong University School of Medicine, Shanghai200025，China
Corresponding author：LI Hong-wei，E-mail：hwli@263.net
Abstract    Hereditary thyroid cancer includes familial nonmedullary thyroid cancer (FNMTC) and hereditary medullary thyroid cancer (HMTC). FNMTC may occur as a minor component of familial cancer syndromes or as a primary feature, with higher rates of multicentric tumors, lymph node metastasis, extrathyroidal invasion and shorter disease-free survival. A hereditary predisposition to nonmedullary thyroid cancer is well established, but the susceptibility genes for isolated FNMTC have not been identified. In the other hand, HMTC is a model of genetically determined cancer in which both diagnostic and therapeutic strategies rely on the identification of specific mutations. It may be observed with either multiple endocrine neoplasia syndromes 2A and 2B or as FMTC. The early diagnosis is especially important, and the genetic testing and direct DNA analysis allows the identification of asymptomatic patients. Surgical prophylaxis should be considered in the cases, ideally to prevent the development of MTC.