[Could Helicobacter pylori treatment reduce stomach cancer risk?]

Abstract

Despite its dramatic decline in incidence in developed countries, gastric cancer is a major public health issue in the world. Accumulating evidence for considering H. pylori as a causal factor for gastric cancer comes from recent epidemiologic studies, the advent of an animal model of gastric cancer and from new insights into the biological mechanisms for gastric carcinogenesis. The stomach cancer risk for people infected with H. pylori is rather low, inferior to 1%. It depends on genotypic polymorphisms of both the bacterium and the host. Environmental risk factors such as smoking habits, salt intake, and the amount of antioxidants in diet may interfere with H. pylori and modify the cancer risk. There is no definite clinical evidence of the benefit of eradication on cancer risk in humans due to the lack of randomized controlled studies in large populations. The occurrence of gastric adenocarcinomas in patients after complete remission of gastric MALT lymphoma induced by H. pylori eradication suggests also the limits of the preventive strategy against gastric cancer. Furthermore, the effectiveness of eradication to reverse precancerous gastric lesions such as severe atrophy and intestinal metaplasia is questionable. For many reasons discussed in our review, population-based screening and routine eradication of H. pylori infection seem to be an unrealistic goal and cannot be recommended in France. By waiting for effective anti-H. pylori vaccine, public health measures such as dietary modification should be promoted to further decrease the gastric cancer incidence. On the individual basis the specialist has a role in the diagnosis of gastric precancerous lesions by endoscopy and also in the prevention of gastric cancer by selecting indications for H. pylori therapy.