Gastric cancer: ENVIRONMENTAL RISK FACTORS AND H PYLORI Part 2

28 Mar
2012

Helicobacter pyloriThe World Health Organization’s International Agency for Research on Cancer has recently classified H pylori as a group 1 or definite carcinogen. The etiological role of H pylori in gastric cancer was based on Correa’s model: chronic atrophic gastritis to intestinal metaplasia, dysplasia and finally carcinoma. H pylori has been shown to be strongly associated with gastric atrophy and intestinal metaplasia. Large case control and cohort studies have shown the relationship between H pylori and adenocarcinoma in both the intestinal and the diffuse types of gastric cancer. H pylori infection has been estimated to increase the risk of gastric cancer sixfold. Tsugane et al found that in a Japanese population, higher salt intake correlated with a higher prevalence of H pylori infection. It was postulated that gastric mucosal damage caused by high salt intake facilitated H pylori infection. The gastric juice of H pylori-positive individuals had a lower concentration of vitamin C than H pylori-negative individuals, but the concentration returned to normal when H pylori was eradicated. Therefore, vitamin C could play an important role in preventing the damage caused by H pylori through its antioxidant effect. Lower socioeconomic status was associated with a higher prevalence of H pylori. However, large interventional studies are needed to directly prove the causative role of H pylori in gastric carcinogenesis. On the other hand, the association of H pylori with cancer of the gastric cardia is more controversial. Learn how to save money – buy cheap antibiotics to enjoy your shopping and your treatment.

Despite the proposal of dietary and environmental factors, and the identification of H pylori, the rapid global decline in gastric cancer is still not fully explainable. An interesting hypothesis that has been proposed as a pivotal point for the decline is the popularization of refrigerators. Refrigerators improve the storage of food, thereby reducing salting for preserving food, and preventing bacterial and fungal contamination of food. Refrigeration also enables fresh food and vegetables to be more readily available, which may be a valuable source of antioxidants important for cancer prevention.

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