First-line treatment and second-line treatment, in clinical terms, mainly refer to the treatment modality adopted by tumor patients. First-line refers to the interventions taken in the first treatment, including, of course, surgery and chemotherapy drugs. Second line refers to the first treatment failure, or after a period of time, like chemotherapy patients, after six to eight times of chemotherapy, it may cause resistance to chemotherapy drugs, thus the tumor treatment can not play a therapeutic role, this time you can consider the second line treatment plan, but usually the effect of second line treatment should be inferior to the first line treatment. In addition, the first-line drugs and second-line drugs are also the case. First-line drugs are the preferred drugs, while second-line drugs are considered because the organism is resistant to the first-line drugs.