Gastric cancer is one of the malignant tumors of digestive tract that seriously endangers human life, and it is the fourth most common malignant tumor in the world, accounting for the third place in the death rate of malignant tumors globally. The survival rate of gastric cancer patients is closely related to the degree of progression of gastric cancer. Although there is only one word difference between early gastric cancer and advanced gastric cancer, the cure rate and postoperative quality of life of early gastric cancer and advanced gastric cancer are very different. The 5-year survival rate of early gastric cancer is more than 90%, while the 5-year survival rate of middle and late gastric cancer is only 20%~30%. In recent years, with the rapid development of gastrointestinal endoscopy technology, especially the application of gastroscopy, the diagnosis rate of early gastric cancer has been greatly improved. Then what is Gastroscopy Precision Screening? Who needs to be examined? What is Gastroscopy? To put it simply, gastroscopy is a gastroscopic examination that uses optical technologies such as high-definition, magnification, staining, and confocal laser microendoscopy to standardize and refine the evaluation of high-risk patients or suspected lesions. The so-called high-definition is that the equipment has a high-brightness light source, high-quality picture quality display, high-definition endoscopy, as if everyone buys a TV and a monitor, the demand for picture quality is getting higher and higher. Magnification is the technology of gastroscopy fine examination. Magnified gastroscopy is a digestive endoscopy method that increases the zoom lens of the endoscope on the basis of ordinary electronic endoscopy, so that the mucosal tissues are optically magnified 1.5 to 150 times. Through magnified gastroscopy to observe the changes in the microstructure of the mucosal surface of the digestive tract, such as the opening of the glandular ducts, microvessels and capillaries, to determine the pathological nature of the mucosal lesions, to clarify the scope of the infiltration of the lesions and to improve the accuracy of the biopsy. Staining is the use of electronic staining and chemical staining methods, so that the digestive tract shows some special changes, easier to find lesions. Confocal laser microendoscopy is a special gastrointestinal examination technology that combines gastrointestinal endoscopy and confocal laser microscopy technology into one, which has extremely high resolution, and can observe the fine structure that cannot be observed by ordinary endoscopy, and provide instant histological diagnosis of cells. What are the characteristics of gastroscopy fine examination 1, preoperative preparation should be adequate. Gastroscopy fine examination 15~30 minutes before the examination, the patient is given mucus dissolving agent streptavidin and expectorant dimethylsilicone oil in order to completely remove the mucus and air bubbles in the upper gastrointestinal tract, effectively improve the clarity of the field of vision, in order to improve the detection rate of small lesions. 2. Long examination time. The average time of ordinary gastroscopy is about 5 minutes, while the gastroscopy fine examination time is longer, and each part is observed at least twice or more. If suspicious lesions are found, chemical and electronic staining can be used, and magnified endoscopic fine examination can be used, so as to determine the specific location, scope and morphology of the lesion, and to guide the precise biopsy of the abnormal part, and to take photos for record at the same time. 3.High personnel and equipment requirements. Gastroscopic microscopy has high requirements for personnel, and the endoscopist who has been trained in early cancer microscopy and has rich experience must carry out more detailed examination, so as to better find the lesions and make reasonable examination and judgment. Gastroscopy requires the brand, model and quality of gastroscope, as well as image enhancement technology such as pigment endoscopy/electronic coloring endoscopy or magnifying endoscopy. It also needs to be combined with ultrasound gastroscopy if necessary. Who needs Gastroscopy? The main target of Gastroscopy is the high-risk group of upper gastrointestinal tumors. The following people who meet the requirements of Article 1 and any of Articles 2~7 can be designated as the high-risk group of upper gastrointestinal tumors. 1.Age >=40 years old, male or female. 2. People in areas with high incidence of upper gastrointestinal tract tumors. 3. People with Helicobacter pylori infection. 4, People with upper gastrointestinal symptoms: abdominal distension, early satiety, belching, acid reflux, nausea, loss of appetite and so on. 5.Pre-cancerous state of upper gastrointestinal tract: chronic atrophic gastritis, intestinal epithelial hyperplasia, heterogeneous hyperplasia (intraepithelial neoplasia), gastric polyp, gastric remnant, gastroesophageal ulcer, gastritis remnant, Barrett’s esophagus, etc. 6.Have clear family history of upper gastrointestinal tract cancer. 7.High risk factors of upper gastrointestinal tract cancer: heavy smoking, heavy drinking, head, neck and throat tumors. Through the four tests of gastric function combined with the gastric cancer screening scoring system, those with scores greater than 17 are also the target of gastroscopic fine screening.