Radiotherapy is one of the three major clinical treatments for tumors (surgery, radiotherapy and chemotherapy). According to statistics, the overall 5-year cure rate of malignant tumors treated by comprehensive therapy is 45%, of which surgery contributes 22%, radiotherapy 18% and chemotherapy 5%. Patients who cannot tolerate other therapies because of their age, poor physical condition or multiple surgeries can receive radiotherapy. 3.The effect of treatment is reliable and the treatment method is reliable. 4.The treatment process is simple, painless and easily accepted by patients. 5.Treatment side effects are minimal, avoiding anesthesia accidents caused by surgery, blood transfusion reactions, postoperative infections, and side effects such as hair loss and vomiting caused by chemotherapy. 6.Radiation therapy is non-invasive and can preserve the physiological functions of the diseased organs.