title: Association between the presence of H pylori in the liver and hepatocellular carcinoma: a meta-analysis.
abstract: OBJECTIVE
  To evaluate the arguments for and against the possible roles of H pylori in hepatocellular carcinoma (HCC).
  
  
  METHODS
  We performed a systematic review of all relevant studies published in the literature. A total of 103 clinical trials and reports were identified, but only 10 trials qualified under our selection criteria. A meta-analysis was carried out by a biostatistician according to the Cochrane Reviewers' Handbook recommended by The Cochrane Collaboration.
  
  
  RESULTS
  Nine case-control studies and one retrospective cross sectional study were included in the final analysis. Overall the prevalence of H pylori infection was 53.3% (129 of 242) in cases and 10.4% (29 of 280) in controls, and the summary odds ratio for the association of H pylori infection with the risk for HCC (using the fixed-effects model, which accounted for the homogeneity across the 10 studies) was determined to be 13.63 (95% CI, 7.90-23.49).
  
  
  CONCLUSIONS
  Our analysis showed a positive association between H pylori infection and the risk of HCC, with an indication of possible publication bias and possible confounders due to study designs that showed results of less pronounced associations.
authors.affiliation: College of Medicine and Pharmaceutics, Ocean University of China, 5 Yushan Road, Qingdao 266003, Shandong Province, China.
authors.forename: Shi-Ying
authors.initials: SY
authors.lastname: Xuan
authors.forename: Yong-Ning
authors.initials: YN
authors.lastname: Xin
authors.forename: An-Jin
authors.initials: AJ
authors.lastname: Chen
authors.forename: Quan-Jiang
authors.initials: QJ
authors.lastname: Dong
authors.forename: Xin
authors.initials: X
authors.lastname: Qiang
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Ming-Hua
authors.initials: MH
authors.lastname: Zheng
authors.forename: Hua-Shi
authors.initials: HS
authors.lastname: Guan
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000453:epidemiology*; D016481:Helicobacter Infections / Q000453:epidemiology*; D016480:Helicobacter pylori; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology*; D012307:Risk Factors