title: [Impact of tumor size on survival in stage I A non-small cell lung cancer].
abstract: BACKGROUND
  The influence of tumor size on prognosis has been determined in different stages of lung cancer, but it is not clear yet within the same stage of lung cancer, especially for those less than 3cm in diameter. The aim of this study is to explore the impact of tumor size on prognosis in stage IA non-small cell lung cancer (NSCLC).
  
  
  METHODS
  A total of 142 consecutive, surgically treated patients with pathologic stage IA NSCLC were analysed retrospectively. Kaplan-Meier survival curve was performed to estimate the survival of patients with different tumor size. And a COX proportional hazard regression model was used to make multivariate analysis about age, gender, pathologic type, tumor size and chemoradiotherapy or not.
  
  
  RESULTS
  There were 60 patients with tumor diameter less than 2.0cm, and 82 between 2.1 to 3.0cm. The overall 3-and 5-year survival rate was 84.41% and 70.89% respectively, in which tumor diameter less than 2.0cm group was 94.91% and 81.40%, tumor diameter between 2.1 to 3.0cm group was 82.18% and 64.91% (P=0.0353), respectively. In both univariate and multivariate analyses, the tumor size was an independent prognostic factor for survival.
  
  
  CONCLUSIONS
  Since the tumor size is an independent prognostic factor for NSCLC, it is necessary to improve the level of imageological diagnosis so as to treat the patients much earlier.
authors.affiliation: Department of Thoracic Tumor, Beijing Tuberculosis and Thoracic Tumor Hospital, Beijing 101149, P.R.China.
authors.forename: Shuku
authors.initials: S
authors.lastname: Liu
authors.forename: Shaofa
authors.initials: S
authors.lastname: Xu
authors.forename: Zhidong
authors.initials: Z
authors.lastname: Liu
authors.forename: Fugen
authors.initials: F
authors.lastname: Li
authors.forename: Yi
authors.initials: Y
authors.lastname: Han