title: Hereditary medullary thyroid cancer: age-appropriate thyroidectomy improves disease-free survival.
abstract: BACKGROUND
  Twenty-five percent of medullary thyroid cancer (MTC) cases are hereditary. The ideal age for prophylactic thyroidectomy is based on the specific RET mutation involved. The purpose of this study was to determine whether such age-appropriate prophylactic thyroidectomy results in improved disease-free survival.
  
  
  METHODS
  Twenty-eight patients underwent thyroidectomy for hereditary MTC at our institution. Age-appropriate thyroidectomy was defined according to the North American Neuroendocrine Tumor Society (NANETS) guidelines. Patients who had age-appropriate surgery (group 1, n = 9) were compared to those who had thyroidectomy past the recommended age (group 2, n = 19).
  
  
  RESULTS
  The mean age was 13 ± 2 years, and 61 % were female. Patients in group 1 were younger than in group 2 (4 ± 1 vs. 17 ± 2 years, p < 0.01). There were no significant differences in gender or RET mutation types between these two groups. Group 1 patients were cured with no disease recurrence compared with group 2 patients who had a 42 % recurrence rate (p = 0.05). Subanalysis of group 2 identified that patients who underwent surgery without evidence of disease did so at a shorter period following the guidelines compared with those who underwent therapeutic surgery (2 ± 2 vs. 16 ± 2 years, p = 0.01) and had longer disease-free survival (100 vs. 27 %, p = 0.005).
  
  
  CONCLUSIONS
  Patients with hereditary MTC should undergo age-appropriate thyroidectomy based on RET mutational status to avoid recurrence. Patients who are past the recommended age should have surgery as early as possible to improve disease-free survival.
authors.affiliation: Section of Endocrine Surgery, Department of Surgery, University of Wisconsin, Madison, WI, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Shepet
authors.forename: Amal
authors.initials: A
authors.lastname: Alhefdhi
authors.forename: Ngan
authors.initials: N
authors.lastname: Lai
authors.forename: Haggi
authors.initials: H
authors.lastname: Mazeh
authors.forename: Rebecca
authors.initials: R
authors.lastname: Sippel
authors.forename: Herbert
authors.initials: H
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000367:Age Factors; D018276:Carcinoma, Medullary / Q000151:congenital* / Q000235:genetics / Q000517:prevention & control / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D018813:Multiple Endocrine Neoplasia Type 2a / Q000235:genetics / Q000517:prevention & control / Q000601:surgery*; D009364:Neoplasm Recurrence, Local; D017410:Practice Guidelines as Topic; D051096:Proto-Oncogene Proteins c-ret / Q000235:genetics; D013964:Thyroid Neoplasms / Q000235:genetics / Q000517:prevention & control / Q000601:surgery*; D013965:Thyroidectomy; D013997:Time Factors
chemical_list: D051096:Proto-Oncogene Proteins c-ret; C099282:RET protein, human