Depending on the site of colon cancer, the amount of bleeding, and the rate of bleeding, the bleeding manifestations may be slightly different, and may manifest as blood in the stool, black stool and blood in the stool. If the bleeding volume is very large, there may also be signs of insufficient circulation, such as dizziness, panic, profuse sweating, decreased blood pressure, increased heart rate and other clinical manifestations. If colon cancer progresses to narrow the intestinal lumen, bleeding can be accompanied by intestinal obstruction manifestations, such as abdominal distension, nausea and vomiting. Because it is a malignant tumor, bleeding can be accompanied by other clinical manifestations, manifestations of tumor metastasis to distant places, such as ascites, right upper abdominal pain, chest tightness, shortness of breath, cough and other manifestations.