Geographical variations in Helicobacter pylori gastritis and gastric cancer

The variability in occurrence of gastric cancer in different parts of the world can be partly explained by geographical differences in the prevalence of Helicobacter pylori. However, variability in the incidence of gastric carcinoma in countries with similar prevalences of H. pylori infection exists, This variability suggests that additional factors, other than H. pylori, also play a role in the progression of H. pylori infection to lesions which increase the risk of gastric neoplasia, Among the mechanisms proposed are the differences in aggressiveness of H. pylori strains, differences in the host response against the microorganism, genuine capacity of the host to secrete acid, diet and other environmental factors.