Manager Tan is 42 years old and has just returned home from studying MBA abroad to work as a general manager in a large company in China. He is busy with all kinds of socializing and socializing all day long, and he is very happy in his work. Recently, he found that the back of the hand unexplained erythema and capillary dilatation, hyperpigmentation, and often feel muscle swelling, local pressure pain, and even serious arm activity disorder. Because of his busy schedule, he did not go to the hospital for examination. A few days ago, the above symptoms gradually aggravated. He had no choice but to go to the hospital for checkup and was found to be in the advanced stage of stomach cancer. It turned out that these symptoms were the accompanying symptoms of stomach cancer. People may think it is strange that stomach is in charge of digestion, and symptoms related to digestive tract, such as epigastric distension, nausea, loss of appetite, etc., which are similar to those of gastritis and gastric ulcer, should appear in the case of stomach cancer. However, if the gastrointestinal symptoms are not obvious and the gastric cancer is mainly manifested outside the stomach, it is easy to be neglected by patients, family members and even medical personnel and the best time for treatment will be missed. These special symptoms may appear before the awareness of gastric cancer, and some of them may disappear after the resection of the cancer. The first “extra-gastric” manifestations of common gastric cancer mainly include: 1. Anemia: due to the long-term chronic and small amount of blood seepage from the ulcerated surface of gastric cancer, resulting in iron-deficiency anemia, the patients often feel tired, lethargy and black stools, etc. Even some ulcerative gastric cancers can be manifested as the first manifestation because of vomiting of blood. 2. Recurrent thrombophlebitis (Trousseau syndrome): it is manifested as pallor of limbs, coldness, acidity, fatigue, intermittent claudication, and sensory abnormality, including numbness, tingling and burning sensation. 3.Acanthosis nigricans: skin pigmentation, especially in both armpits; 4.Dermatomyositis:that is, it manifests as erythema and capillary dilatation, hyperpigmentation in the exposed part or the back of the joints; muscle swelling, pressure and pain, and dyskinesia. Carcinoid syndrome: manifested as wheezing or asthma-like difficulty in breathing, paroxysmal tachycardia, watery diarrhea, skin flushing, etc., which is mainly due to excessive secretion of 5-hydroxytryptamine. Metastasis of gastric cancer causes “extra-gastric” symptoms: (1) Liver metastasis is the first manifestation of gastric cancer, and the rate of liver metastasis of gastric cancer is 45.9%-46.5%. Clinically, it mostly manifests as chronic hepatitis and cirrhosis and other liver diseases, such as discomfort in liver area, jaundice, diarrhea and other symptoms. Imaging examination often shows multiple foci, scattered distribution, round shape and clear boundary. (2) Gastric cancer with ovarian metastasis and metastatic foci as the first manifestation accounts for 43.6% of female gastric cancer patients. Clinical manifestations are mostly acute abdominal pain, irregular menstruation, lower abdominal mass and so on, while gastrointestinal symptoms are not obvious. It mostly occurs in pre-menopausal or young women, and both ovaries are involved at the same time, with enlarged ovaries, intact perimenopause, solid or mucus-like section, and some of them can secrete estrogen, therefore, clinically, it often manifests various types of menstrual irregularities. It is easy to be misdiagnosed as simple ovarian tumor. (3) In the case of the first manifestation of enlarged lymph nodes on the surface of the body, gastric cancer with higher degree of malignancy or advanced stage can be metastasized retrogradely to the left supraclavicular lymph node via thoracic duct, or metastasized to the periumbilical area via round ligament of the liver. On physical examination, an enlarged, non-smooth, hard as stone, fixed cancerous nodule with adhesion to surrounding tissues can be detected in the left supraclavicular fossa or periumbilical region. It may also be the first symptom or sign detected in the clinic before gastric cancer is traced out. In addition, if the cancer metastasizes to other organs, there may be manifestations of corresponding involvement including fever, cough, bone pain, hemiplegia and so on. In conclusion, when the above symptoms appear in human body, we should not only stay on the surface of symptoms, but also check in detail whether the cause of symptoms is tumor. In order to avoid delay in diagnosis and treatment.