Does Eradication of Helicobacter pylori Really Decrease Gastric Cancer Incidence and Mortality?

Gastric cancer is the third most common cause of cancer-related death in the world. Through the intestinal metaplasia pathway, Helicobacter pylori is a class 1 carcinogen and a causative agent in the development of gastric cancer. Prior meta-analysis has demonstrated that eradication of H pylori reduces the incidence of, as well as the mortality from, gastric cancer. Two randomized controlled trials (RCTs) have now updated their follow-up data to include 20-plus years of data. This meta-analysis by Ford et al includes 4 RCTs with 10 or more years of follow-up.  

The study analyzed data from 5292 otherwise healthy patients with H pylori infection (2660 received eradication and 2632 received no treatment). The investigators discovered that 69 patients (2.6%) in the eradication group and 127 patients (4.8%) in the no-treatment group developed gastric cancer (relative risk [RR], 0.54; 95% confidence interval [CI], 0.41-0.72). The number needed to treat (NNT) to prevent one gastric cancer was 45 (95% CI, 35-74). 

Mortality was reported in 3 of the RCTs: 47 of 2242 patients (2.1%) who received eradication therapy and 71 of 2233 (3.2%) who received no treatment (RR, 0.66; 95% CI, 0.46-0.95). The NNT to prevent one death from gastric cancer was 92.5 (95% CI, 58-629). 

The NNT to prevent gastric cancer for men younger than 75 years of age in North America, Northern Europe, Central or Eastern Europe, and Eastern Asia was 345, 311, 100, and 57, respectively.