The incidence of gastric cancer and what factors

1) environmental factors in different countries and regions of significant difference in the incidence of notes and related environmental factors, the most important factor is diet.
Salt may be induced by exogenous factors of gastric cancer one of the residents intake of salt and more countries have high incidence of gastric cancer. Nitrosamines compounds have successfully induced gastric cancer in animals. The smoked fish contain more 3,4 - benzopyrene (benzopyrene); Mold food containing more fungal toxins; Rice is processed outside review talc, their chemical nature and structure with asbestos fibers similar to the above substances are considered carcinogenic effect.
(2) genetic factors in some families a higher incidence of gastric cancer. Some information indicates that gastric cancer in the A blood type O blood group than those who were more.
(C) immune factors immunocompromised persons higher incidence of gastric cancer, immune dysfunction may be on the supervisory role of cancer immune decline in the occurrence of gastric cancer in a certain sense.
(D) pre-cancerous changes in the so-called pre-cancerous change is that some of the strong tendency of malignant lesions, lesions that if not dealt with, it is possible for the development of gastric cancer. Pre-cancerous changes include pre-cancerous condition (precancerous conditions) and pre-cancerous lesions (precancerous lesions).
1. The pre-cancerous stomach condition
(1) chronic atrophic gastritis: chronic atrophic gastritis and gastric cancer incidence was significantly positive correlation.
(2) pernicious anemia: pernicious anemia in 10% in patients with gastric cancer, the incidence of gastric cancer normal crowd for the 5 to 10 times.
(3) gastric polyps: type or villous adenoma polyp type of gastric polyps although the proportion is not high, the cancer rate is 15% to 40%. Diameter greater than 2 cm higher cancer rate. Hyperplastic polyps common, and carcinogenesis rate of just 1%.
(4) residual stomach: benign gastric lesions occurred after surgery for gastric carcinoid tumor residual residual said gastric cancer. After surgery especially in the stomach after 10, the rate increased significantly.
(5) benign gastric ulcer: gastric ulcer itself is not a pre-cancerous condition. While the verge of mucosal ulceration is prone to intestinal metaplasia and malignant transformation.
(6) huge gastric folds disease (Menetrier's disease): Serum Protein gastric mucosal folds by the tremendous loss, a clinical hypoproteinemia and edema, about 10% could be cancerous.
2. Gastric pre-cancerous lesions
(1) proliferation and change as Profiled: The former, also known as atypical hyperplasia is caused by chronic inflammation of irreversible pathological cell proliferation, a few cases of the cancer. Gastric change (anaplasia) are cancerous opportunities.
(2) intestinal metaplasia: a type of small intestine and colon of two, intestinal type (complete) with the characteristics of the small intestinal mucosa, differentiation better. Colorectal type (not complete) with large intestinal similar, can be divided into two subtypes: a type II, non-sulfuric acid secretion can of mucin; B-II can sulfate of mucin secretion, this type of close relationship with gastric cancer.