The early manifestations of colon cancer are generally very mild, mainly as follows: First, abdominal symptoms mainly include abdominal pain, bloating or anal swelling, and sometimes even abdominal masses can be felt without pressure pain and hard texture, which can move with the intestinal tract. Second, changes in stool characteristics, which can be manifested as thin stools, dark red blood stools or mucus blood stools. Third, changes in bowel habits, which may include diarrhea, or diarrhea, or alternating with constipation or diarrhea. If you take oral medicine for diarrhea or constipation, the symptoms disappear and are not obvious. In conclusion, the early manifestations of colon cancer are very mild and easy to be ignored. If patients have the aforementioned symptoms, they should be alert to the possibility of colon cancer and should go to the hospital as soon as possible.