Tumor recurrence rate after radiotherapy varies, such as advanced nasopharyngeal cancer is around 15%-20%, advanced cervical cancer is about 20%-39%, small cell lung cancer is 52.6%-85.5% and so on. Tumor recurrence rate after radiotherapy is related to tumor type, staging, treatment sensitivity, surgery and other factors. If the tumor stage is early, complete resection can be done by surgery, and the sensitivity to chemotherapy is relatively high, radiotherapy is only an auxiliary means, generally the recurrence rate after radiotherapy is low. If the tumor is staged at an advanced stage, not completely removed by surgery, or cannot be operated, and is not sensitive to chemotherapy, radiotherapy is the main treatment means, and the recurrence rate is on the high side. Tumors may still recur after radiotherapy, but it does reduce its overall recurrence rate, and patients are advised to choose the appropriate treatment plan under the guidance of their doctors, and target therapy, immunotherapy and other options can be used to improve the prognosis if necessary.