Bevacizumab needs to be used all the time. Bevacizumab is a targeted anti-angiogenic drug that needs to be combined with chemotherapy drugs at first for best results. After 4-6 cycles of combined application, if the disease is controlled, chemotherapy drugs can be suspended, but bevacizumab needs to be maintained at all times. If there is a progression of the disease, the 1st progression of bevacizumab can be continued and other chemotherapy drugs need to be replaced. However, if 2nd progression occurs during the use of bevacizumab, it is recommended to change to another targeted drug.