There are more chemotherapy drugs for bowel cancer, and at present, the commonly used ones are mainly three major categories: fluorouracil, platinum (mainly oxaliplatin) and irinotecan, which are as follows: 1. First-line chemotherapeutic drugs: mainly 5-FU (pyrimidines), capecitabine and oxaliplatin, which are capable of killing tumor cells in the body, preventing the tumor from spreading and metastasis, and preventing the tumor from recurring and so on; 2. Second-line chemotherapeutic drugs: For recurrent intestinal cancer or part of patients who have failed first-line treatment, it is necessary to consider the joint application of second-line treatment drugs for treatment, such as irinotecan; 3. Third-line chemotherapy drugs: TAS-102 (pyrimidine drugs), which is applicable to the use of previous drugs after drug-resistance and disease progression; 4. Targeted therapy: for a part of patients with liver metastasis and lung metastasis, it is possible to need to add targeted therapy drugs, such as Western medicine. targeted therapy drugs, such as cetuximab, bevacizumab.