Nowadays, there are actually many people with gastrointestinal problems, and the incidence of gastric cancer is also very high in China, so what exactly are the symptoms of early gastric cancer? Early stage gastric cancer: Most of the patients have no symptoms, and even if they have symptoms, they are not typical, and they are generally manifested as mild discomfort in the upper abdomen, which many friends tend to consider as gastritis with indigestion. Progressive gastric cancer: In this kind of gastric cancer, patients usually have unexplained upper abdominal discomfort or pain, and also have symptoms of bloating, not wanting to eat, and even vomiting blood. Symptoms before death of end-stage gastric cancer: At this time, the general condition of the patient is usually not good anymore, often becoming very thin, weak, not wanting to eat, etc., and may often vomit blood. Therefore, if friends have some symptoms, they must go to the hospital early to find out if it is stomach cancer. Then how to diagnose stomach cancer in clinical practice? The examination methods of gastric cancer: 1.Fiber endoscopy is the most direct, accurate and effective method to diagnose gastric cancer. 2.Exfoliative cytology examination Some scholars advocate to perform this examination when gastric cancer is suspected by clinical and X-ray examinations. 3.B ultrasound can understand whether there is metastasis in the surrounding organs. 4.CT examination can understand the invasion of gastric tumor, the relationship with surrounding organs and the possibility of resection. 5.Laboratory examination In early stage of suspected gastric cancer, there is a low level of free gastric acid or deficiency, such as a decrease in red blood cell pressure, hemoglobin and red blood cell, and fecal occult blood (+). Low total hemoglobin, white/bulb inversions, etc. Water-electrolyte disorders, acid-base imbalance and other laboratory abnormalities. 6.X-ray performance of gas-barium dual imaging can clearly show the stomach outline, peristaltic movement, mucosal morphology, emptying time, the presence of filling defects, niches, etc. The accuracy rate of examination is nearly 80%. Gastric cancer must be distinguished from gastric ulcer, simple polyps in the stomach, benign tumor, sarcoma, and chronic inflammation in the stomach. Gastric cancer is distinguished from other malignant tumors: (1) Gastric primary malignant lymphoma: Gastric primary malignant lymphoma accounts for 0.5%-8% of gastric malignant tumors, mostly seen in young adults, and is usually found in the gastric sinus, with clinical manifestations similar to those of gastric cancer. X-ray signs are irregular thickening of diffuse gastric mucosal folds, irregularly patterned multiple ulcers, large folds in the mucosa at the edge of the ulcers, single or multiple round filling defects, and “goose eggstone-like” changes. Gastric lymphoma should be considered first when gastroscopy reveals huge gastric mucosal folds, single or multiple polypoid nodules, and surface ulcers or erosions. (2) Gastric smooth muscle sarcoma: Gastric smooth muscle sarcoma accounts for 0.25%-3% of gastric malignant tumor, accounting for 20% of gastric sarcoma, mostly seen in the elderly, preferably in the gastric body of the fundus, tumors are often >10cm, spherical or hemispherical, and large ulcers may appear due to ischemia. According to the location, it can be divided into: (1) intragastric type (submucosal type), where the tumor protrudes into the gastric cavity; (2) extragastric type (subplasma type), where the tumor grows outside the stomach; and (3) gastric wall type (dumbbell type), where the tumor grows both inside and outside the stomach.