Chemotherapy is a common treatment for malignant tumors in clinical practice. The reason why the first chemotherapy is the most critical is that tumor cells are drug-resistant. Generally, the drug has the strongest ability to kill tumor cells in the first chemotherapy, and after that, tumor cells will gradually tolerate the drug, so the effect is not as obvious as the first one. However, this does not mean that the subsequent chemotherapy is meaningless. On the contrary, the subsequent chemotherapy has an important role for patients who are not suitable for surgical treatment and for the removal of residual lesions after surgery, therefore, tumor patients should insist on chemotherapy. Therefore, patients with tumor should insist on chemotherapy. Due to the different development of patients’ disease, the specific regimen of chemotherapy also differs. Patients need to adopt targeted chemotherapy under the guidance of professional doctors to achieve better treatment effect. Usually, chemotherapy is divided into the following categories according to different purposes of chemotherapy: 1. Systemic chemotherapy: if patients are in advanced stage of cancer, or if cancer cells have spread or metastasized extensively, they need to adopt systemic chemotherapy under the guidance of doctors to achieve the effect of controlling the development of disease; 2. 2.Adjuvant chemotherapy: After surgery, there may be residual cancer cells in the body, in order to prevent their spread, patients need to undergo adjuvant chemotherapy; 3.Neoadjuvant chemotherapy: For patients who are not suitable for surgery or radiotherapy, they need to adopt neoadjuvant chemotherapy to reduce the size of malignant tumor and avoid damage to various organs, which can improve the survival rate and quality of life to a certain extent 4.Special route chemotherapy: mainly includes intracavitary, intralesional and arterial cannulation chemotherapy, which has the function of controlling the primary as well as metastatic lesions. Therefore, patients should develop a treatment plan in time after the disease under the guidance of doctors and start the first chemotherapy as early as possible, which is beneficial to the prognosis of the disease.