What causes gastric cancer

What causes gastric cancer? Gastric cancer is not unfamiliar to all of us. It is a common malignant tumor of the digestive tract and ranks first among our various malignant tumors. The incidence rate is very high, which seriously threatens everyone's health and life. So, what causes gastric cancer? Let's find out together.

1. Regional environment and dietary lifestyle factors

There are obvious regional differences in the incidence of gastric cancer. The incidence of gastric cancer in the northwest and eastern coastal areas of my country is significantly higher than that in the southern region. The incidence of distal gastric cancer is high among people who have long consumed smoked, roasted, and salted foods, which is related to the high content of carcinogens or pro-carcinogens such as nitrites, fungal toxins, and polycyclic aromatic hydrocarbons in food. The risk of gastric cancer in smokers is 50% higher than that in non-smokers.

2. Helicobacter pylori infection

The Hp infection rate among adults in high-incidence areas of gastric cancer in my country is over 60%. Helicobacter pylori can promote the conversion of nitrates into nitrites and nitrosamines, which are carcinogenic. Hp infection causes chronic inflammation of the gastric mucosa, and environmental pathogenic factors accelerate the excessive proliferation of mucosal epithelial cells, leading to aberration and carcinogenesis. The toxic products of Helicobacter pylori, CagA and VacA, may have a carcinogenic effect. The detection rate of anti-CagA antibodies in gastric cancer patients is significantly higher than that in the general population.

3. Precancerous lesions

Gastric diseases include gastric polyps, chronic atrophic gastritis, and residual stomach after partial gastrectomy. These lesions may be accompanied by varying degrees of chronic inflammatory processes, intestinal metaplasia or atypical hyperplasia of the gastric mucosa, and may turn into cancer. Precancerous lesions refer to pathological histological changes in the gastric mucosa that are prone to canceration. They are borderline pathological changes in the process of transformation from benign epithelial tissue to cancer. Dysplasia of the gastric mucosal epithelium is a precancerous lesion. It can be divided into three degrees: mild, moderate, and severe according to the degree of cell atypia. Severe dysplasia is sometimes difficult to distinguish from well-differentiated early gastric cancer.

4. Heredity and genes

Genetic and molecular biological studies have shown that the incidence of gastric cancer in blood relatives of gastric cancer patients is 4 times higher than that in the control group. The carcinogenesis of gastric cancer is a multi-factor, multi-step, and multi-stage development process involving changes in oncogenes, tumor suppressor genes, apoptosis-related genes, and metastasis-related genes, and the forms of gene changes are also diverse.

Gastric diseases are closely related to the occurrence of gastric cancer. A large proportion of patients develop gastric cancer due to the deterioration of gastric lesions. Some gastric diseases such as atrophic gastritis, intestinal metaplasia, gastric ulcer, gastric polyps, etc. can all lead to the occurrence of gastric cancer. The prognosis of gastric cancer is related to the pathological stage, location, tissue type, biological behavior and treatment measures of gastric cancer. The prognosis of early gastric cancer is better after treatment.