title: Hereditary medullary thyroid carcinoma: the management dilemma.
abstract: Hereditary medullary thyroid carcinoma (hereditary MTC) is a rare malignancy, accounting for 25-30% of all MTC. It occurs as part of multiple endocrine neoplasia type 2 (MEN 2). Autosomal dominant gain-of-function mutations in the RET proto-oncogene is the cause of the disease, in which the common mutations are codons 609, 611, 618, 620, 630, 634 and 918. In recent years, the spectrum of RET gene mutations has changed. The classical mutations reduced, whereas the less aggressive mutations increased. Hereditary MTC is a time-dependent disease. Stages of the disorder at diagnosis can significantly influence survival rates. Based on the genotype-phenotype, RET mutations have been classified into four risk levels by American Thyroid Association (ATA) at 2009. The classification system guides the hereditary MTC management, including risk assessment, biochemical screenings and surgical intervention. Though the application of genetic testing and codon-specific phenotypes in hereditary MTC diagnosis is effective with high accuracy, there are some difficulties in implementing RET gene testing as a routine for MTC diagnosis. And most of carriers with RET mutations did not undergo thyroidectomy at the age recommended by the ATA guidelines. The aim of the study is to review the hereditary MTC and discuss the management dilemma.
authors.affiliation: Department of Surgical Oncology, The First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang Province, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhou
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.forename: Shao-Wen
authors.initials: SW
authors.lastname: Cheng
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.forename: Rong
authors.initials: R
authors.lastname: Yang
authors.forename: Ling
authors.initials: L
authors.lastname: Peng
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D018276:Carcinoma, Medullary / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology / Q000601:surgery*; D018278:Carcinoma, Neuroendocrine; D056726:Genetic Association Studies; D005820:Genetic Testing; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D000090063:Proto-Oncogene Mas; D051096:Proto-Oncogene Proteins c-ret / Q000235:genetics*; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology / Q000601:surgery*; D013965:Thyroidectomy
chemical_list: C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D051096:Proto-Oncogene Proteins c-ret