Generally, patients need a combination of 2~3 chemotherapy drugs, a course of about 2~4 weeks, and the duration of single chemotherapy dose is mostly about 5 days. Chemotherapy is an important means of anti-tumor treatment, but the time of chemotherapy is not fixed, which is related to tumor category, pathological type, pathological staging, program and drug selection, preoperative and postoperative status. For example, postoperative adjuvant chemotherapy for breast cancer, clinically commonly used fluorouracil + cyclophosphamide + azithromycin drugs three-drug combination, a course of three weeks, but most of the chemotherapeutic drug infusion time is only one day. Chemotherapy is a common postoperative adjuvant treatment for tumor patients, there are also some preoperative use of neoadjuvant chemotherapy, or patients with advanced tumors, you can also do palliative chemotherapy so as to improve the quality of survival of patients. The specific cycle of chemotherapy and the duration of a single session of chemotherapy are determined by professional oncologists according to the severity of the patient’s condition, individual situation and the therapeutic effect of chemotherapy, etc. It is recommended that patients actively cooperate with the treatment and should not take medication without authorization.