M. Asaka et al., REVIEW ARTICLE - LONG-TERM HELICOBACTER-PYLORI INFECTION - FROM GASTRITIS TO GASTRIC-CANCER, Alimentary pharmacology & therapeutics, 12, 1998, pp. 9-15
An analysis carried out in 1994 by the WHO International Agency for Re
search on Cancer (IARC) resulted in Helicobacter pylori being designat
ed as a Group 1 carcinogen and thus clearly having an association with
the development of gastric cancer. In the case of H. pylori, the eval
uation was made solely on the basis of epidemiological results. In Jap
an, in 1993, only 235,000 of the 60 million people with H. pylori had
gastric cancer. This represents only 0.4% of the infected population.
Each individual reacts in a unique way to H. pylori infection in terms
of the inflammatory response. The probability of developing cancer wi
ll be determined by environmental factors such as diet, duration of or
age at acquisition of H, pylori infection, the virulence of H, pylori
strains, and host factors including genetic make-up.