title: Helicobacter pylori eradication cannot reduce the risk of gastric cancer in patients with intestinal metaplasia and dysplasia: evidence from a meta-analysis.
abstract: BACKGROUND
  The effect of Helicobacter pylori (H. pylori) eradication on gastric cancer (GC) prevention is controversial. Intestinal metaplasia (IM) seems to be a "point of no return" in the precancerous cascade. We performed a meta-analysis of randomized controlled trials (RCTs) to illustrate this issue.
  
  
  METHODS
  The MEDLINE, EMBASE, Cochrane Library were searched for relevant RCTs that were published in any language up to March 2014. By dividing participants into subgroups based on their baseline diagnoses as group <IM (normal, non-atrophic gastritis, atrophic gastritis) and group ≥ IM(intestinal metaplasia, dysplasia), the relative risk (RR) of GC in each study compared treatment group with control group were pooled using Mantel-Haenszel fixed-effect model and publication bias analyses were performed.
  
  
  RESULTS
  Ten studies from eight RCTs were included in this analysis, for a total of 7,955 participants. H. pylori treatment compared with control significantly reduced the risk of GC, with a pooled RR of 0.64 (95% CI, 0.48-0.85). Subgroup analysis for patients with non-atrophic gastritis, atrophic gastritis (<IM) yielded a similar results (RR = 0.25, 95% CI, 0.08-0.81). But this difference was not observed in patients with intestinal metaplasia, dysplasia (≥ IM) (RR = 0.88; 95% CI, 0.59-1.31).
  
  
  CONCLUSIONS
  Our results suggested that patients with Intestinal metaplasia or dysplasia could not benefit from the H. pylori treatment on the risk of GC.
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Hai-Ning
authors.initials: HN
authors.lastname: Chen
authors.affiliation: Institution of Interventional Radiology, West China Hospital, Sichuan University, Chengdu, China.|Department of Gastroenterology, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Institution of Interventional Radiology, West China Hospital, Sichuan University, Chengdu, China. simonlixiao@126.com.
authors.forename: Xiao
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, China. zhou767@hotmail.com.
authors.forename: Zong-Guang
authors.initials: ZG
authors.lastname: Zhou
mesh_terms: D005753:Gastric Mucosa / Q000382:microbiology / Q000473:pathology*; D005757:Gastritis, Atrophic / Q000150:complications / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D006801:Humans; D008679:Metaplasia / Q000382:microbiology; D011230:Precancerous Conditions / Q000382:microbiology / Q000473:pathology / Q000517:prevention & control; D016032:Randomized Controlled Trials as Topic; D013274:Stomach Neoplasms / Q000382:microbiology / Q000473:pathology* / Q000517:prevention & control*
keywords: Gastric cancer; Helicobacter pylori treatment; Precancerous lesions