Gastritis and gastric cancer - Western countries

Helicobacter pylori infection is the cause of chronic gastritis that progre sses to atrophic gastritis over years and decades in more than half of affe cted individuals. H. pylori gastritis and, particularly, subsequent atrophi c gastritis increase the risk for gastric cancer on multifactorial basis. L argely unknown cascades of manifold reactions result in gene errors of epit helial cells in gastric and atrophic stomach, which raise the likelihood of gastric neoplasias and cancer among people infected by H. pylori. The prev alences and incidences of gastric cancer and H. pylori are similarly decrea sed during the past decades in western countries, supporting the view that H, pylori infection is a key event and a trigger of the phenomena that resu lt in cancer in some of the infected subjects.