Gastric cancer refers to malignant lesions of the epithelial cells of the gastric mucosa. At present, the incidence of gastric cancer is still high, so why do some people have gastric cancer on their first gastroscopy? It is generally believed that gastric carcinogenesis is not a sudden leap from normal cells to cancer cells, but a gradual process, which often undergoes years of continuous precancerous changes before developing into cancer. Currently, the more recognized pattern is: chronic active gastritis – chronic atrophic gastritis – intestinalization – atypical hyperplasia – gastric cancer. -gastric cancer. It can be seen that those who are found to have gastric cancer at the first gastroscopy have actually had the disease for many years, only that the symptoms may not be very typical and they do not seek examination from doctors. How does gastric cancer occur? The occurrence of gastric cancer is related to genetic, environmental or dietary factors, among which food factors and H. pylori infection (Hp) are more important. High salt intake, pickled and smoked food, and overnight unfresh food are all causative factors, and infection with H. pylori is also a recognized cancer-causing factor. Huang Shi, Department of Gastroenterology, Rui Kang Hospital, Guangxi University of Traditional Chinese Medicine