title: Acceptable age for prophylactic surgery in children with multiple endocrine neoplasia type 2a.
abstract: OBJECTIVE
  Germline mutated RET proto-oncogene, causing multiple endocrine neoplasia (MEN)-2a syndrome is the indication for prophylactic total thyroidectomy. Literature regarding the risk and the extent of early surgical intervention is scarce and the optimum age for surgery is still controversial. To optimize management in these young children we evaluate our experience and results.
  
  
  METHODS
  From 1990 to 2001 preventive total thyroidectomy was performed in 13 MEN-2a gene carriers (4 boys and 9 girls; median age 7 (4-14) years). Preoperative assessment, surgical procedure, pathological examination, postoperative complications and treatment results were studied.
  
  
  RESULTS
  Surgery existed of a total thyroidectomy alone (n=3) in children with normal basal calcitonin and in combination with tracheo-esophageal exploration (n=6) or central compartment dissection (n=4) in case of abnormal calcitonin levels. Eight children presented with medullary thyroid cancer (MTC), three (median: 5 (4-12) years) with microscopic MTC and five (median 6 (4-14) years) with frank invasive MTC. Four of these five patients were younger than 6 years. Except for long-lasting hypoparathyroidism in one patient there were no complications. At a median follow-up of 6.5 years all patients are disease free.
  
  
  CONCLUSIONS
  MTC in RET mutated MEN-2a gene carriers in childhood are found at the age of 4 years. Therefore, DNA testing should be done preferably before that age. Preventive surgery can be performed safely at that age and may be limited to total thyroidectomy when baseline calcitonin levels are normal.
authors.affiliation: Department of Surgical Oncology/Head and Neck Surgery, University Hospital Groningen, Groningen, The Netherlands. j.th.plukker@chir.azg.nl
authors.forename: T
authors.initials: T
authors.lastname: Kahraman
authors.forename: J W B
authors.initials: JW
authors.lastname: de Groot
authors.forename: C
authors.initials: C
authors.lastname: Rouwe
authors.forename: R M W
authors.initials: RM
authors.lastname: Hofstra
authors.forename: Th P
authors.initials: TP
authors.lastname: Links
authors.forename: R H
authors.initials: RH
authors.lastname: Sijmons
authors.forename: J Th M
authors.initials: JT
authors.lastname: Plukker
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002116:Calcitonin / Q000097:blood; D002648:Child; D002675:Child, Preschool; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D006579:Heterozygote; D006801:Humans; D008297:Male; D018813:Multiple Endocrine Neoplasia Type 2a / Q000097:blood / Q000175:diagnosis / Q000235:genetics / Q000517:prevention & control* / Q000601:surgery*; D009154:Mutation; D015513:Oncogene Proteins / Q000235:genetics*; D000090063:Proto-Oncogene Mas; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D013965:Thyroidectomy / Q000379:methods; D016896:Treatment Outcome
chemical_list: D004273:DNA, Neoplasm; C000715470:MAS1 protein, human; D015513:Oncogene Proteins; D000090063:Proto-Oncogene Mas; D002116:Calcitonin; D051096:Proto-Oncogene Proteins c-ret; C099282:RET protein, human; D020794:Receptor Protein-Tyrosine Kinases