Precancerous risk markers in Helicobacter pylori gastritis

Primarily on the basis of epidemiological evidence, Helicobacter pylori was classified as a definite human carcinogen in 1994. Although several pathop hysiological consequences of chronic H. pylori gastritis have been identifi ed which may contribute to the development of gastric carcinoma, it is stil l largely unknown why only a minority of individuals infected with H.pylori (approximately 1/1000) develop this fatal disease. In recent years many st udies have examined potential risk factors of H. pylori gastritis to improv e our understanding of the early events in gastric carcinogenesis. The pres ent paper summarizes research data supporting the following hypotheses: (a) Some H. pylori possess Virulence factors which may contribute to the patho genicity of the organism and may increase the risk for subsequent severe ga stroduodenal diseases such as gastric cancer. However, the associations bet ween these virulence factors and disease is not specific, and may vary cons iderably among different geographic regions. (b) Chronic H. pylori gastriti s induces several pathophysiological alterations which may promote cancer d evelopment. In particular,the corpus-dominant phenotype of H.pylori gastrit is is strongly associated with gastric cancer.(c) A family history of gastr ic cancer per se, but also in combination with H. pylori infection, is asso ciated with histopathological and molecular alterations that are considered relevant in gastric carcinogenesis.