Clinical manifestations】 Early gastric cancer is mostly asymptomatic or has only mild symptoms. When the clinical symptoms are obvious, the lesion is already in advanced stage. Therefore, we should be very alert to the early symptoms of gastric cancer to avoid delaying the diagnosis and treatment. 1. Symptoms (1) Early gastric cancer: With the development of the disease, the function and circumstance of the stomach gradually change, and these symptoms are often non-specific, may appear from time to time, and may exist for a long time. Such as epigastric distension, dull pain, vague pain, nausea, loss of appetite, belching and emaciation, etc.; a few ulcerated (type IIc and type III) early gastric cancers can also have ulcer-like symptoms, rhythmic pain and acid reflux, which can be relieved by medical treatment, etc. In some patients, gastric cancer coexists with or occurs on the basis of certain benign lesions (such as chronic atrophic gastritis, peptic ulcer, etc.), and the symptoms of these benign gastric diseases have existed for a long time or recurrently, which makes patients and doctors relax their alertness to gastric cancer and delay the diagnosis. Some early gastric cancers can also present with symptoms such as vomiting blood, black stool, or difficulty in swallowing, and so on. Wu Longxiang, Department of Hepatobiliary Oncology, Nantong Cancer Hospital ① Upper abdominal discomfort: it is the most common initial symptom of gastric cancer, about 80% of patients have this symptom, similar to dyspepsia, if abdominal pain occurs, it is generally mild and irregular at the beginning, but cannot be relieved after eating and gradually worsens, it can be vague or dull pain. Some of them can have rhythmic pain, especially sinus gastric cancer, which is more obvious and can even be relieved by eating or taking medicine. Elderly people have dull pain sensation and mostly complain of abdominal distension. These symptoms are often not taken seriously by patients, and are easily mistaken for gastritis or ulcer disease when they seek medical attention. Therefore, middle-aged patients should be given further examination to avoid missing the diagnosis if they have the following conditions: A. No previous history of gastric disease, but recent unexplained epigastric discomfort or pain that has been ineffective after treatment; B. Previous history of gastric ulcer and recent change in the regularity of epigastric pain with increasing severity. If the symptoms are relieved, but there is another episode within a short period of time, the possibility of gastric cancer should also be considered and further examination should be conducted in time. Nearly 50% of gastric cancer patients have obvious symptoms of loss of appetite or loss of appetite, and some of them restrict eating on their own because too much food will cause abdominal distension or pain. Unexplained anorexia and weight loss are probably the initial symptoms of early gastric cancer, which need to be taken seriously. Patients with early gastric cancer usually have no obvious positive signs, and most of them only have deep pressure pain in the upper abdomen in addition to weak general condition. (2) Progressive gastric cancer: Gastric cancer is a progressive process from small to large, from superficial to deep, from no metastasis to metastasis, therefore, there is no obvious boundary between early, progressive and even late stages, not only that, there is often a great crossover of symptoms between stages. Some patients present with symptoms of organ metastasis or comorbidities. According to domestic statistics, common symptoms of progressive gastric cancer are as follows: ① Abdominal pain: when gastric cancer develops and expands, especially when the infiltration penetrates the plasma membrane and invades the pancreas or the transverse colon lining, it may cause persistent and severe pain and radiates to the lower back. Very few patients with perforated cancer ulcers may also have severe abdominal pain and signs of peritoneal irritation. ②Loss of appetite and wasting: the absorption of toxins from cancer can make patients increasingly appear wasting, weakness, anemia, and malnutrition, which is often progressively aggravated and finally manifests as cachexia. Nausea and vomiting: It is also one of the more common symptoms, which can occur in early stage. Gastric sinus cancer may also show symptoms of pyloric obstruction. ④Vomiting blood and black stool: when ulcers are formed on the surface of cancer, then vomiting blood and black stool will appear. 1/3 of gastric cancer patients often have small amount of bleeding, which is mostly manifested as positive fecal occult blood, and some of them may have intermittent black stool, but some of them also visit the doctor with large amount of vomiting blood. (5) Diarrhea: It may be related to low gastric acid, and the stool may be paste-like or even have five-shift diarrhea. When advanced gastric cancer involves the colon, it often causes diarrhea and bloody stools. (6) Difficulty in swallowing: after the cancer grows up, obstruction symptoms may appear, pancreatic or fundic cancer may cause difficulty in swallowing, and sinus cancer may cause pyloric obstruction symptoms. 2.Signs Early gastric cancer may not have any physical signs. Or there is only pressure pain in the upper abdomen. In middle and late stage gastric cancer, most of the epigastric pressure pains are obvious. 1/3 of the patients can have palpable lumps in the abdomen, which are hard, with unsmooth surface and tenderness, especially the lumps are more easily to be found in the wasted patients with sinus cancer. As for metastases such as prerectal masses, umbilical masses, enlarged supraclavicular lymph nodes and ascites, they are more evidence of advanced gastric cancer. Upper abdominal mass, anterior rectal palpable mass, umbilical mass, left supraclavicular lymph node enlargement, left axillary lymph node enlargement and ascites often suggest the presence of distant metastasis. The clinical manifestations are often complicated by the corresponding signs depending on the metastatic sites. For example, liver metastasis may lead to liver enlargement and jaundice, ovarian metastasis may lead to ovarian enlargement and large amount of ascites, and lung metastasis may lead to respiratory distress. In addition, gastric cancer with cancer syndrome can be an important sign, such as thrombophlebitis, dermatomyositis, etc. Advanced patients may have fever, cachexia, etc. Diagnosis】 1.Symptoms. Early stage is epigastric discomfort, about 80% of patients have this symptom, and nearly 50% of patients with gastric cancer have obvious loss of appetite or loss of appetite. In the late stage, weakness, low back pain and nausea, vomiting and difficulty in eating may appear after obstruction. In case of tumor surface ulceration, blood vomiting and black stool may appear. 2. Physical signs. In the early stage, there is no special sign, but in the late stage, epigastric mass, rectal finger diagnosis can be found, the left supraclavicular lymph node is enlarged, at the same time, anemia, emaciation, ascites and other cachectic manifestations. 3.Laboratory examination. Early suspicion of gastric cancer, low free gastric acid or deficiency, such as decreased erythrocyte pressure, hemoglobin and red blood cells, and fecal occult blood (+). Low total hemoglobin, white/bulb inversions, etc. Water-electrolyte disorders, acid-base imbalance and other laboratory abnormalities. 4.X-ray performance of gas-barium double imaging can clearly show the stomach outline, peristalsis, mucosal morphology, emptying time, the presence of filling defects, niche shadow, etc.. The accuracy rate of examination is nearly 80%. 5.Fiber endoscopy is the most direct, accurate and effective diagnostic method to diagnose gastric cancer. 6.Exfoliative cytology examination Some scholars advocate to perform this examination when gastric cancer is suspected by clinical and X-ray examination. 7.B ultrasound can understand whether there is metastasis in the surrounding organs. 8.CT examination can understand the invasion of gastric tumor, the relationship with surrounding organs and the possibility of resection. 9.Immunological CEA, FSA, GCA, YM globulin and other examinations. Patients with middle and late stage gastric cancer mostly have upper abdominal symptoms and systemic manifestations, and it is not difficult to determine the diagnosis through barium X-ray fluoroscopy and gastroscopy, etc. Early gastric cancer often has no clear symptoms, which can easily delay the diagnosis. Clinicians should be more alert to gastric cancer. Patients above middle age, those with recent persistent upper abdominal discomfort, loss of appetite, weight loss, black stool or repeated positive fecal occult blood tests, especially those who have lived in areas with high incidence of gastric cancer for a long time, or those with chronic atrophic gastritis with intestinal glandular hyperplasia and atypical hyperplasia, those with history of gastric ulcer and previous gastrointestinal anastomosis, and those with history of gastric cancer among relatives should undergo barium meal and gastroscopy in order to make a clear diagnosis in time.