title: Epidermal growth factor receptor mutations and their correlation with gefitinib therapy in patients with non-small cell lung cancer: a meta-analysis based on updated individual patient data from six medical centers in mainland China.
abstract: BACKGROUND
  Convincing data on epidermal growth factor receptor (EGFR) mutations in Chinese patients with non-small-cell lung cancer (NSCLC) remain limited. We investigated the relevance of demographic characteristics and EGFR mutations, correlations between the efficacy of gefitinib and EGFR mutations in NSCLC, and to identify individuals who would likely benefit from gefitinib.
  
  
  METHODS
  We conducted a meta-analysis based on updated individual patient data from six medical centers in mainland China. Outcome measures included the EGFR mutation status, demographic characteristics, response, and survival.
  
  
  RESULTS
  Among 506 patients with NSCLC who received EGFR mutation analysis, the EGFR mutation rate was 30.04%. Patients with adenocarcinoma had a higher mutation rate than those with non-adenocarcinoma (44.1% vs 9.2%; p < 0.00001). The EGFR mutation rate for smokers was 15.1%, lower than that for non-smokers (45.5%) (p < 0.00001). Male patients had a lower mutation rate than female patients (23.1% vs 42.9%; p < 0.0001). Multivariate analysis showed that "adenocarcinoma" and "non-smoker" were independent predictors of EGFR mutations. In a subgroup of 57 patients with complete treatment data, the response rate to gefitinib in the EGFR mutant group was 60.7%, significantly higher than that in the wild-type EGFR group (17.2%) (odds ratio, 5.78; 95% CI, 1.95-17.13; p = 0.002). "EGFR mutation", "adenocarcinoma," and "non-smoker" were independent predictors of response. Overall survival in the EGFR mutant group and the wild-type group did not differ significantly (hazard ratio, 0.60; 95% CI, 0.32-1.12; p = 0.110). "Adenocarcinoma status" was an independent prognostic factor for survival.
  
  
  CONCLUSIONS
  In mainland China, "adenocarcinoma" and "non-smoker" are independent predictors for EGFR mutations. Response to gefitinib favors patients with EGFR mutations. The clinical selected populations for gefitinib are non-smokers with adenocarcinoma.
authors.affiliation: Lung Cancer Research Institute & Cancer Center, Guangdong Provincial People's Hospital, Guangzhou, China. gzyilong2006@hotmail.com
authors.forename: Yi-Long
authors.initials: YL
authors.lastname: Wu
authors.forename: Wen-Zhao
authors.initials: WZ
authors.lastname: Zhong
authors.forename: Long-Yun
authors.initials: LY
authors.lastname: Li
authors.forename: Xiao-Tong
authors.initials: XT
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Cai-Cun
authors.initials: CC
authors.lastname: Zhou
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Jiang
authors.forename: Xin-Lin
authors.initials: XL
authors.lastname: Mu
authors.forename: Jia-Ying
authors.initials: JY
authors.lastname: Lin
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhou
authors.forename: Chong-Rui
authors.initials: CR
authors.lastname: Xu
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.forename: Guo-Chun
authors.initials: GC
authors.lastname: Zhang
authors.forename: Tony
authors.initials: T
authors.lastname: Mok
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000235:genetics*; D016009:Chi-Square Distribution; D002681:China; D004252:DNA Mutational Analysis; D066246:ErbB Receptors / Q000235:genetics*; D000077156:Gefitinib; D006801:Humans; D016015:Logistic Models; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics*; D016016:Proportional Hazards Models; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use*; D011799:Quinazolines / Q000627:therapeutic use*; D012307:Risk Factors; D016019:Survival Analysis
chemical_list: D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D066246:ErbB Receptors; D000077156:Gefitinib