Digestive system cancer patients may have digestive system symptoms such as discomfort and pain in the upper abdomen, acid reflux and belching, accompanied by generalized common symptoms such as emaciation and easy fatigue. 1. Digestive system symptoms: (1) Discomfort and pain in the upper abdomen: at the beginning, it may only be distending pain or vague pain, which may be caused by local mucous membrane damage and stimulation. With the progress of the disease, the tumor invades into the plasma membrane layer of the tissue, and the abdominal pain will be gradually aggravated. (2) Acid reflux and belching: cancer of digestive system will lead to weakening of digestive function, which will cause abnormal secretion of gastric acid, and then symptoms of acid reflux, nausea and belching will appear. 2. Systemic system reaction: (1) Wasting: with the development of the disease, digestive system cancer patients may have erosion and ulceration of the digestive tract, which in turn affects the digestion and absorption function of the patients, leading to extreme wasting. (2) Tiredness: with the development of the disease, cancer cells grow vigorously, which depletes the energy of the whole body, so the phenomenon of easy fatigue will occur. In addition to the above common symptoms, patients with digestive system cancer may also have constipation, blood discharge symptoms and other abnormal phenomena. When patients experience any discomfort, they should go to the hospital for consultation and early treatment.