Helicobacter pylori and gastric cancer

Epidemiological studies have consistently shown an association between infection with Helicobacter pylori and gastric cancer. The strongest evidence comes from three prospective studies that have shown the risk of gastric cancer to be increased by about fourfold in infected individuals. This raises the possibility of preventing a substantial number of gastric cancer cases by controlling H. pylori. Screening asymptomatic populations and eradicating the organism in those infected is the only treatment strategy currently available, but several questions remain to be answered before this can be recommended as a routine public health measure. Research into H. pylori has transformed understanding of the aetiology of gastric cancer, focusing attention on factors such as chronic inflammation, impaired host defence mechanisms and oxidative cell damage.