Vague pain in the left side of the abdomen and frequent exhaustion are considered to be lesions of the intestinal tract, which should be combined with colonoscopy if there are obvious abnormalities in defecation. Because it is common to have colitis, or tumors occurring in the colon, patients may also have abdominal symptoms aggravated after eating, accompanied by loss of appetite and weight loss. Patients with intestinal tumors should actively choose surgery in the early stage. There are certain predisposing factors for the occurrence of tumors, such as frequent overeating, irregular eating, or eating too much fatty food at dinner, intestinal digestive disorders, and previous history of intestinal polyps or ulcers, all of which are likely to induce cancer, so colonoscopy should be performed regularly. After surgery, patients with early diagnosis also need regular checkups, and some patients need systemic intravenous chemotherapy if necessary.