Approximately 70% of malignant tumors require radiation therapy. Almost all tumors in all parts of the body can be treated with radiotherapy. Some benign tumors can also be treated with radiotherapy, such as intracranial cavernous hemangioma, pituitary tumor, craniopharyngioma, meningioma, auditory neuroma, etc.; postoperative body scar tumor, postoperative lymphangioleioma, etc. In general, the side effects of radiotherapy are very small, mainly local reactions, which are related to the site of radiotherapy. For example, the main side effects of oropharyngeal radiotherapy are congestion and redness of oral mucosa, erosion and ulceration; dryness of oropharynx, etc. There are no obvious side effects in chest radiotherapy, but patients need to prevent from getting cold, otherwise it is easy to induce lung infection. In abdominal pelvic radiotherapy, because the intestinal mucosa is sensitive to radiotherapy, flatulence, diarrhea, loss of appetite and other indigestion symptoms may occur.