title: PD-L1 over-expression and survival in patients with non-small cell lung cancer: a meta-analysis.
abstract: BACKGROUND
  Observational studies on the prognostic role of programmed cell death-ligand 1 (PD-L1) in non-small cell lung cancer (NSCLC) are controversial.
  
  
  METHODS
  To clarify the impact of PD-L1 in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios (HR) and their corresponding 95% confidence intervals (CIs) were calculated in terms of overall survival.
  
  
  RESULTS
  A total of five studies with 877 patients were evaluable for this meta-analysis. Our results suggested that PD-L1 overexpression had a poor impact on survival of patients with NSCLC, the HR (95% CI) was 1.43 (1.24-1.63) overall, 1.51 (1.24-1.7954) in Asian patients, 1.35 (1.08-1.63) in non-Asian patients. Moreover, there was no heterogeneity between the studies.
  
  
  CONCLUSIONS
  PD-L1 overexpression indicates a poor prognosis for patients with NSCLC.
authors: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China.
authors: Ze-Jun
authors: ZJ
authors: Zhou
authors: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China.
authors: Ping
authors: P
authors: Zhan
authors: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China.
authors: Yong
authors: Y
authors: Song
keywords: Programmed cell death-ligand 1 (PD-L1); lung cancer; meta-analysis; prognosis