title: Aggressive medullary thyroid cancer, an analysis of the Irish National Cancer Registry.
abstract: OBJECTIVE
  Medullary thyroid cancer consists of a spectrum of disease that ranges from extremely indolent tumors to aggressive types associated with a high mortality rate. The objective of our study is to evaluate the prognostic factors and outcomes of patients diagnosed with MTC in a homogenous population, and to examine patients diagnosed with MTC for mutations in the RET proto-oncogene from the same period.
  
  
  METHODS
  A retrospective analysis of the National Cancer Registry in Ireland was undertaken, between 1998 and 2007. The Kaplan-Meier method was used to determine overall survival and factors predictive of outcome were determined by univariate and multivariate analysis by cox regression using Stata 13 software.
  
  
  RESULTS
  Forty-three patients were diagnosed with medullary thyroid cancer, 55.8 % were female and 44.2 % were male. A median age of 52 was found. The overall median survival was 6.32 years and the 1- and 5-year overall survival was 88.37 and 62.79 %, respectively, with 10-year survival calculated at 48.63 %. On univariate analysis age, stage and surgical intervention were statistically significant indicators of prognosis. T stage and age remained statistically significant indicators of prognosis on multivariate analysis. Two patients with no history of MEN syndromes or family history of medullary thyroid cancer had RET proto-onocogene mutations.
  
  
  CONCLUSIONS
  Our patient cohort was substantially older and presented at an advanced T status than what is commonly seen in the literature. This may account for poor survival outcomes and the very low pick-up of RET mutations in sporadic medullary thyroid cancer.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, St. James's Hospital, Dublin 8, Ireland. paullennon81@gmail.com.
authors.forename: P
authors.initials: P
authors.lastname: Lennon
authors.affiliation: National Cancer Register, Ireland, Cork, Ireland.
authors.forename: S
authors.initials: S
authors.lastname: Deady
authors.affiliation: Department of Clinical Genetics, Our Lady's Children's Hospital, Crumlin, Ireland.
authors.forename: N
authors.initials: N
authors.lastname: White
authors.affiliation: Department of Clinical Genetics, Our Lady's Children's Hospital, Crumlin, Ireland.
authors.forename: D
authors.initials: D
authors.lastname: Lambert
authors.affiliation: Department of Endocrinology, St. James's Hospital, Dublin 8, Ireland.
authors.forename: M L
authors.initials: ML
authors.lastname: Healy
authors.affiliation: Department of Clinical Genetics, Our Lady's Children's Hospital, Crumlin, Ireland.
authors.forename: A
authors.initials: A
authors.lastname: Green
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, St. James's Hospital, Dublin 8, Ireland.
authors.forename: J
authors.initials: J
authors.lastname: Kinsella
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, St. James's Hospital, Dublin 8, Ireland.
authors.forename: C
authors.initials: C
authors.lastname: Timon
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Beaumont Hospital, Dublin, Ireland.
authors.forename: J P
authors.initials: JP
authors.lastname: O' Neill
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018278:Carcinoma, Neuroendocrine / Q000235:genetics / Q000473:pathology*; D005260:Female; D006801:Humans; D007494:Ireland; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011379:Prognosis; D000090063:Proto-Oncogene Mas; D051096:Proto-Oncogene Proteins c-ret / Q000235:genetics*; D012042:Registries; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000235:genetics / Q000473:pathology*; D055815:Young Adult
chemical_list: C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D051096:Proto-Oncogene Proteins c-ret
keywords: Calcitonin; Cancer registry; Database; Medullary thyroid cancer; RET proto-oncogene; Survival