title: Human papillomavirus-related esophageal cancer survival: A systematic review and meta-analysis.
abstract: BACKGROUND
  Human papillomavirus (HPV) has been identified to be related to progression of esophageal cancer. However, the results remain controversial. A meta-analysis of epidemiologic studies was therefore conducted to address this issue.
  
  
  METHODS
  The electronic databases of MEDLINE and Excerpta Medica database were searched till April 30, 2016. Study-specific risk estimates were pooled using a random-effects model.
  
  
  RESULTS
  Ten studies involving a total of 1184 esophageal cancer cases were included in this meta-analysis. The pooled hazard ratio comparing HPV-positive to HPV-negative esophageal cancers was 1.03 (95% confidence interval 0.78-1.37), which was not significantly correlated with improved survival. However, HPV-16-positive patients might have a significantly favorable survival (hazard ratio 0.73, 95% confidence interval 0.44-1.21).
  
  
  CONCLUSIONS
  The meta-analysis indicated that HPV infection may not be of prognostic utility in the evaluation of factors contributing to esophageal cancer. Further large prospective studies are encouraged to stratify survival analysis by HPV type.
authors.affiliation: Department of Cancer Epidemiology, Henan Office for Cancer Control and Research, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China.
authors.forename: Lanwei
authors.initials: L
authors.lastname: Guo
authors.forename: Shuzheng
authors.initials: S
authors.lastname: Liu
authors.forename: Shaokai
authors.initials: S
authors.lastname: Zhang
authors.forename: Qiong
authors.initials: Q
authors.lastname: Chen
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.forename: Peiliang
authors.initials: P
authors.lastname: Quan
authors.forename: Xi-Bin
authors.initials: XB
authors.lastname: Sun
mesh_terms: D018450:Disease Progression; D004938:Esophageal Neoplasms / Q000453:epidemiology* / Q000821:virology*; D006801:Humans; D027383:Papillomaviridae / Q000472:pathogenicity*; D030361:Papillomavirus Infections / Q000453:epidemiology* / Q000821:virology*; D011379:Prognosis; D016019:Survival Analysis