With the increase in the average age of our nation and the change in diet structure, the incidence of colorectal cancer has also increased quietly. As a colorectal oncologist, I deeply feel the weight of responsibility on my shoulders. Here, I hope to give some suggestions and guidance to the life and treatment of tumor patients through my own summary. In order to defeat the enemy, we must first have a full understanding of the enemy. First of all, let us understand what is colorectal cancer. The total length of large intestine is about 2 meters, including appendix, cecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum and anus. Colorectal cancer is a tumor of the digestive system formed by the malignant transformation of mucosal epithelial cells of the large intestine. Among our Chinese colorectal cancers, rectal cancer accounts for the highest proportion, and most rectal cancer patients show blood in the stool. Recently, it has been found that the proportion of patients with ascending colon is gradually increasing, and the clinical symptoms of these patients are often not easy to detect (often with symptoms of anemia such as weakness, pale face or abdominal pain), and the disease is often more serious at a later stage when treated. Common symptoms of colorectal cancer include blood in stool, thinning of stool, incomplete bowel movement, abdominal pain, diarrhea and constipation, etc., among which symptoms related to change in bowel habits are most common. Besides, abdominal mass and bloating are also common.