The main symptom of mid-stage bowel cancer is that patients will experience hidden pain or distension in the abdomen, in addition, they will show increased frequency of stool, blood in stool, or deformation of stool, such as thin stool, etc. There are many patients whose first symptom is increased frequency of stool. When intestinal tumor is first discovered, many patients mainly show more frequent stools, such as 1-3 times of stools per day. When the tumor grows further and the surface of the tumor breaks down, it will manifest as blood in the stool, such as black stool, dark red blood stool, bright red blood stool and so on. It is only when the tumor grows further that it may manifest local pain, and there may even be a mass in the abdomen when the pain is obvious. Patients are advised to do colonoscopy, abdominal CT and other related examinations.