The main difference between radiotherapy and chemotherapy: one is local treatment and the other is systemic treatment. Radiotherapy is a kind of local treatment, which uses radiation to kill cancer cells and control local recurrence, and can be used for postoperative adjuvant radiotherapy and palliative radiotherapy for advanced tumors, which can also shrink tumors and relieve symptoms. Chemotherapy is a kind of systemic treatment, that is, chemical drug treatment, which can reach the whole body and prevent metastasis to distant places, but of course, it also depends on the effect of treatment. Generally, radiotherapy is a course of treatment, which may be 4-5 weeks, and chemotherapy may be 6-8 courses of treatment, with an interval of three weeks between each course of treatment, and the drugs need to be given according to the course of treatment, so as to achieve better results. Radiotherapy or chemotherapy may cause some myelosuppression and other reactions, such as white blood cell decline, anemia, platelet reduction, etc., which need to be treated symptomatically.