title: [Identification and validation of prognostic factors in differentiated thyroid carcinoma].
abstract: BACKGROUND
  The aims of this study are to identify prognostic factors of differentiated thyroid carcinoma and to validate the application of prognostic classifications obtained by others studies to another population.
  
  
  METHODS
  The survival of 208 patients with differentiated thyroid carcinoma (129 papillary and 79 follicular carcinoma) was calculated by the Kaplan-Meier method. The mean follow-up was 7.5 years (1-17.7). Cox-proportional hazard model was used for variables influencing on survival (Mantel-Cox method). In addition, the EORTC, AGES, AJC, AMES and DeGroot classifications were tested.
  
  
  RESULTS
  The independent prognostic factors identified were patient age > 60 years, tumor size > 6 cm and the presence of distant metastases. The absence of poor prognostic factors defined the low risk group (153 patients, survival 97% at 17.7 years of follow-up). The application of the other prognostic classifications differentiated several risk groups not in accordance with those obtained in the initial population.
  
  
  CONCLUSIONS
  In this series of patients with thyroid carcinoma the main prognostic factors were age, tumor size and the presence of distant metastases. However, there are pitfalls in applying the prognostic classifications of published studies to another population.
authors.affiliation: Servicio de Endocrinología, L'Hospitalet de Llobregat, Barcelona.
authors.forename: N
authors.initials: N
authors.lastname: Gómez Arnaiz
authors.forename: I M
authors.initials: IM
authors.lastname: Gómez Sáez
authors.forename: M
authors.initials: M
authors.lastname: Sahún de la Vega
authors.forename: R
authors.initials: R
authors.lastname: Abós
authors.forename: C
authors.initials: C
authors.lastname: Villabona Artero
authors.forename: J
authors.initials: J
authors.lastname: Soler Ramón
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000401:mortality*; D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D016019:Survival Analysis; D013964:Thyroid Neoplasms / Q000401:mortality*
vernacular_title: Identificación y validación de factores pronósticos del cáncer diferenciado de tiroides.