According to the retrospective surveys of malignant tumor deaths in 1973-1975 and 1990-1992 conducted by the health department, gastric cancer has the highest mortality rate among all malignant tumors, with 19.54/100,000 and 25.16/100,000 respectively, which is on the rise. With the economic development of the country and the improvement of medical level, although the incidence and mortality rate of most diseases are decreasing, according to WHO, the incidence/death rate of gastric cancer in China will continue to increase at an average annual rate of 3% in the next 20 years. According to the latest data released by the National Cancer Center and the National Cancer Prevention and Treatment Research Office, the incidence and mortality rate of gastric cancer in China continued to rise in 2015, of which the overall incidence rate was 679.1/100,000, and the incidence rate of male patients was significantly higher than that of female patients (male to female incidence rate ratio was 2.7:1), and the male to female mortality rate ratio was 2.1:1, so how to prevent gastric cancer is a major issue facing our oncologists. How to prevent gastric cancer is a major issue facing our oncologists. 1. Don’t take it lightly that the disease comes from the mouth, and regular diet is important to ensure health. Long-term exposure to direct or indirect carcinogens in food may increase the incidence of stomach cancer. Smoking and frying can produce polycyclic aromatic hydrocarbons in food, among which 3,4-benzopyrene is related to the occurrence of gastric cancer, and some people believe, for example, that the incidence of gastric cancer in Iceland has decreased significantly due to the increase in the consumption of fresh food and the decrease in smoked food. Aflatoxin and heterotoxin contained in moldy food can also induce gastric cancer. Carcinogenic precursors in plant and animal foods such as secondary amines and nitrites can be transformed into nitrosamines under certain conditions, thus leading to gastric cancer. In addition, salt itself has no carcinogenic effect, but the increased susceptibility or synergistic carcinogenicity of the gastric mucosa caused by salt may be the reason to increase the risk of gastric cancer. A long-term high salt diet can damage the gastric mucosa and increase the contact with carcinogenic substances, which has certain cancer-promoting effects. Imbalance of nutritional intake may also be related to gastric cancer. Due to the lack of nutrients intake leading to the decrease of body immunity, while vitamin A and C have certain protective effect on gastric mucosa and promote the development of epithelial cells, the lack of the above nutrients may increase the incidence of gastric cancer. Therefore, it is easy to see that scientific diet is very important if you want to keep away from stomach cancer. Most adult men have more or less the habit of smoking and drinking alcohol, which may be one of the reasons why the incidence of stomach cancer is much higher in men than in women. In epidemiological studies, it is clear that smoking is closely related to the occurrence of gastric cancer. Smoking is an extremely important causative factor in approximately 28% of gastric cancer cases and is an independent incidence factor. Stomach cancer caused by smoking is more common in the lower part of the stomach. The smoke from smoking contains many harmful substances such as nicotine, and like smoked and fried foods, the large amount of harmful substances in the smoke is also strongly carcinogenic, increasing the risk of many cancers and cardiovascular and cerebrovascular accidents, not just stomach cancer. Therefore, it is important to quit smoking, regardless of health risks. Once surgery is required for gastric cancer, the risk of lung infection during and after surgery is greatly increased if lung function is compromised by long-term smoking, thereby increasing the mortality rate of perioperative disease. Alcohol consumption is also an independent risk factor for the development of gastric cancer. Although alcohol itself is not a carcinogen, long-term alcohol abuse can lead to acute and chronic damage to the gastric mucosa and promote the contact between carcinogens and gastric mucosa, which is prone to carcinogenesis during the repeated repair process. The risk of stomach cancer increases exponentially if you have both alcohol and smoking habits. 3.Chronic diseases are harmful, and it is too late to regret after accumulation The pathogenesis pattern of gastric cancer, especially intestinal gastric cancer, is a multi-stage process under the role of multiple factors. Some chronic gastric diseases, such as chronic atrophic gastritis, intestinal epithelial hyperplasia and heterotypic hyperplasia of gastric mucosa are related to the development of gastric cancer. Precancerous lesions of the stomach, including atrophic gastritis, intestinal epithelial hyperplasia, severe atypical hyperplasia and carcinoma in situ, are a series of mucosal histopathological changes that predispose to carcinogenesis, and are also a necessary process of gastric tissue carcinogenesis. In addition, some benign diseases such as gastric ulcer and gastric polyp can lead to a significantly increased risk of gastric cancer, called precancerous diseases. Chronic atrophic gastritis is characterized by atrophy and reduction of gastric mucosal glands, often accompanied by varying degrees of intestinal epithelial hyperplasia of the gastric mucosa. Patients with chronic atrophic gastritis are at increased risk of developing gastric cancer and should be closely followed up. According to the results of long-term follow-up studies and animal experimental studies, most scholars now believe that chronic gastric ulcer can become cancerous, and its incidence is about 0.5%~5%. As a precancerous state, the relationship between residual stomach and gastric cancer has also been emphasized. It is generally advocated that cancer occurs in the remnant stomach more than 10 years after major gastrectomy for benign lesions. The development of gastric cancer is a long process, including non-atrophic gastritis, atrophic gastritis, intestinal epithelial hyperplasia, atypical hyperplasia, carcinoma in situ, early gastric cancer, progressive gastric cancer, advanced metastatic gastric cancer, etc. When the disease is in the fashion of non-atrophic gastritis, it can be reversed by medication, but once it develops into the stage of atrophic gastritis, it is impossible to reverse and recover by medication, so regular gastroscopic monitoring is necessary, and once it is detected Once cancerous tendency is detected, gastroscopic or surgical resection should be performed in time. 4.Stomach cancer is caused by stress and mental tension. Long-term mental stress and fatigue will put people in a subhealthy state, which will greatly affect body functions and, most importantly, cause the body’s immunity to decline. The normal human body has a large number of cells in division every day, and a considerable number of them may undergo mutations, but generally they will not develop into tumors. This is mainly due to the existence of a certain immune surveillance mechanism in the body. The immune system identifies and specifically kills mutated cells through cellular immunity, so that the mutated cells are removed before they form tumors. Therefore, the improvement of immunity is indeed very important for the prevention and treatment of cancer. There is a limit to the immune surveillance function of the body. When the immune surveillance function cannot remove the mutated cells or the mutated cells can evade the surveillance ability of the host, the mutated cells can develop into tumors. Therefore, the decrease of immunity due to mental stress is an important cause of cancer. In addition, mental factors such as continuous excessive mental stress, emotional stress and depression can contribute to the occurrence and recurrence of gastric ulcers. Excessive stress can cause excessive secretion of gastric acid and decreased mucosal repair ability. Today it is possible to lead to stress ulcers, long-term ulcers can not be cured will increase the risk of cancer. 5.Small bacteria cause big trouble, and thousands of miles of dike break down anthill Helicobacter pylori (HP) infection is an extremely important factor in the development of gastric cancer. According to statistics, the risk of gastric cancer for HP infected patients is more than 6 times that of uninfected patients. The possible mechanisms of HP infection causing gastric cancer include: HP induces homologous biotoxic inflammatory response promoting excessive value-added of gastric mucosal epithelial cells and increasing free radical formation causing cancer; HP metabolites directly induce apoptosis of gastric mucosal cells; HP DNA is converted to gastric mucosal cells causing cancer. conversion to gastric mucosal cells is carcinogenic, etc. Therefore, the prevention and treatment of HP infection plays an extremely important role in the prevention and treatment of gastric cancer, and should be given high clinical attention. In the previous scientific articles, we have introduced the harmful effects of H. pylori in detail (see the article “Does H. pylori cause gastric cancer?” in the Patient Education Library). For those who are diagnosed positive for H. pylori through breath test or gastroscopy, HP should be eradicated through triple or quadruple therapy under the guidance of a doctor as soon as possible, so as not to let a thousand miles of dike collapse into an anthill because of a momentary carelessness, otherwise it will be too late to regret. About 5-10% of gastric cancers have the tendency to gather in families, and about 3-5% of gastric cancers come from hereditary gastric cancer susceptibility syndrome, including familial adenomatous polyposis, juvenile polyp syndrome, hereditary diffuse gastric cancer, Peutz-Jeghers syndrome, Lynch syndrome, etc. Those who have a family history of hereditary disease and gastric cancer must pay great attention to them, and it is recommended that they must have an annual gastroscopy after the age of 40 to detect lesions and treat them early. Even for those who do not have family history, it is recommended to make it a good habit to have regular checkups, tumor marker screening and routine gastroscopy. In Japan, annual gastroscopy screening has been written into the law. Benefiting from this policy of the Japanese government, the detection rate of early gastric cancer in Japan is higher than 70%, and the cure rate of early gastric cancer is more than 80%, while once it progresses to progressive gastric cancer, the cure rate is only 30%. If you have digestive tract diseases, it is more important to insist on reasonable treatment so as not to leave the hidden danger of stomach cancer. If ignored, once a small disease becomes a big disease, the chance of cure may be lost.