Chemotherapy is also needed after surgery for advanced rectal cancer. Patients with advanced rectal cancer are stage III and IV patients, and stage IV patients also need to have surgery, because without surgery it is likely that the stool cannot be removed and the patient cannot eat or drink, thus leading to the termination of life. After surgery for advanced rectal cancer, patients have to cooperate with doctors to do chemotherapy or local radiotherapy in time, if this aspect of treatment is not done or not done for other reasons, the prognosis is very poor. Therefore, once advanced patients have surgery, they still have to go to medical oncologists for treatment, so that the treatment may prolong the patients’ life and reduce their pain to the best of their ability.