Gastric cancer ranks first among all kinds of malignant tumors in China, and there are obvious geographical differences in the incidence 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. Clinical manifestations Most patients with early gastric cancer have no obvious symptoms, while a few have nausea, vomiting or upper gastrointestinal symptoms similar to ulcer disease. Pain and weight loss are the most common clinical symptoms of progressive gastric cancer. Patients often have clear upper gastrointestinal symptoms, such as upper abdominal discomfort, fullness after eating, and as the disease progresses, upper abdominal pain increases, appetite decreases and weakness. Depending on the location of the tumor, there are also its special manifestations. Gastric cancer near the pylorus has pyloric obstruction; tumor destroying blood vessels can cause gastrointestinal bleeding symptoms such as vomiting blood and black stool. Persistent pain in the abdomen often indicates that the tumor extends beyond the stomach wall, such as enlarged supraclavicular lymph nodes, ascites, jaundice, abdominal mass, and masses in the anterior rectal recess. Patients with advanced gastric cancer may often show anemia, emaciation, malnutrition or even cachexia, etc. Treatment 1.Surgical treatment (1) Radical surgery The principle is to remove part or all of the stomach, including the cancer foci and possibly infiltrated stomach wall, and to remove the lymph nodes around the stomach and reconstruct the digestive tract according to the clinical staging criteria. (2) Palliative surgery The primary foci cannot be removed, and the surgery is performed to relieve the symptoms caused by complications such as obstruction, perforation and bleeding, such as gastrojejunostomy, jejunostomy, perforation repair, etc. 2.Chemotherapy is used before, during and after radical surgery to prolong the survival period. Appropriate amount of chemotherapy for advanced gastric cancer patients can slow down the development of tumor, improve symptoms and have certain recent effects. In principle, adjuvant chemotherapy is not necessary after radical surgery for early gastric cancer. Adjuvant chemotherapy should be performed in the following cases: pathological type with high malignancy; cancer foci larger than 5 cm; multiple cancer foci; age below 40 years. Chemotherapy is needed for those who have progressive gastric cancer after radical surgery, after palliative surgery, or recurrence after radical surgery. The common routes of chemotherapy administration for gastric cancer include oral administration, intravenous and peritoneal administration, and regional perfusion administration by arterial cannulation. Commonly used oral chemotherapeutic agents include tegafur, eflornithine and fluorotiron. Commonly used intravenous chemotherapeutic agents include fluorouracil, mitomycin, cisplatin, amoxicillin, etoposide, calcium formyl tetrahydrofolate, etc. In recent years, new chemotherapeutic drugs such as paclitaxel, platinum oxalate, toprolase inhibitor and Siroda have been used for gastric cancer. 3.Other treatments include radiotherapy, thermotherapy, immunotherapy and Chinese herbal medicine. Immunotherapy for gastric cancer includes non-specific biological response modifiers such as BCG vaccine, mushroom polysaccharide, etc.; cytokines such as interleukin, interferon, tumor necrosis factor, etc.; and clinical application of peripatetic immunotherapy such as lymphocyte activated post-killer cells (IAK), tumor infiltrating lymphocytes (TIL), etc. Anti-angiogenic genes are well-studied gene therapies that may play a role in the treatment of gastric cancer.