Comprehensive treatment plan for gastric cancer needs to be formulated according to specific examination results and staging. 1.According to the preoperative examination and laboratory results, cTNM stage (in reality, it is mostly only cTM stage) is assessed. 2.According to the preoperative staging and the patient’s physical condition, multidisciplinary assessment should be performed for those who can tolerate surgery: (1)T1aM0: EMR (gastroscopic mucosal layer resection), or ESD (gastroscopic mucosal and submucosal layer resection), LWR (laparoscopic wedge resection) and IGMR (laparoscopic intragastric mucosal resection) or surgical R0 resection for D0 or D1 clearance. (2) For T1bM0: R0 resection D2 clearance. (3) T2 and above, M0: R0 resection D2 clearance (or may be + preoperative neoadjuvant chemoradiotherapy). (4) M1, if locally resectable, to improve the quality of life and reduce the cancer load, palliative surgery is feasible, R2~0 resection D0~D2 clearance. (5) For M1, if local resection is not possible, perform gastrointestinal short-circuit surgery to relieve or prepare for gastric obstruction, leave an enteral nutrition tube in a jejunostomy for enteral nutrition input or spare after gastric emptying obstruction or obstruction. (6) If the specific target of drug therapy at the molecular level of cancer cells is found through gastroscopic biopsy before surgery, preoperative neoadjuvant chemoradiotherapy + drug-targeted therapy can be considered for T2 and above. 3.Decide the postoperative treatment plan according to the postoperative pTNM stage: (1) T1aM0,R1 resected: treated according to (4). (2) T1a/1bN0M0,R0 resected patients: clinical observation and follow-up. To deal with possible micro-metastases in negative lymph nodes (currently not detectable by conventional pathological testing), prophylactic application of S-1 (available in domestic tegeo formulation) or capecitabine alone orally may also be considered to improve the cure rate. r1 resected patients are treated as in (4). (3) T2N0M0, R0 resected patients: clinical observation or some patients given chemoradiotherapy, S-1 or capecitabine single agent oral can be considered. R1 resected patients are treated according to (4). (4) T3/4, or any T, but N1-3M0, R0-2 resected: fluorouracil-based (5-Fu or capecitabine) chemotherapy, or concurrent + radiotherapy, consider a multi-drug combination chemotherapy regimen with better efficacy: XELOX, ECF, XP, SO, SP, etc. (5) If postoperative pathological testing reveals specific targets for drug therapy at the molecular level of cancer cells, postoperative adjuvant chemoradiotherapy + drug-targeted therapy can be considered for T2 and above. (6) If preoperative chemoradiotherapy or + drug-targeted therapy is confirmed to be more effective by preoperative imaging or postoperative pathological testing, the regimen should be continued postoperatively, otherwise, the regimen should be changed. (7) Whether postoperative radiotherapy in R0 resected D2 cleared patients can increase the benefit in terms of survival needs to be studied in more countries. The treatment of gastric cancer is still mainly surgical resection The treatment of gastric cancer is still mainly surgical resection, and surgery is the only effective way to treat gastric cancer at present. After decades of development and clinical evidence, the current surgical approach for most resectable gastric cancers is D2 standard radical surgery (with some early-stage gastric cancers undergoing reduction surgery). The standard radical surgery for gastric cancer is not only to remove the tumor of the stomach (gastric ulcer requires removal of the large part of the stomach), but also requires complete clearance of the perigastric lymph nodes, removal of the large and small omentum and pancreatic tegument, etc. Therefore, radical surgery for gastric cancer should never be treated as surgery for benign gastric ulcer, and complete clearance of the perigastric lymph nodes is very important in gastric cancer surgery.