The same site can be radiotherapy twice, but the interval should be at least 1 to 2 years, the specific interval should be based on the radiotherapy site, the dose and other comprehensive judgment. The same site can be radiotherapy twice, but not a short time in the same part of the radiotherapy, generally at least 1 to 2 years between the interval, should be based on the site of the first radiotherapy, the dose used in radiotherapy, radiotherapy mode, radiotherapy after the adverse reaction and the patient’s own body tolerance for comprehensive judgment. Avoid irreversible damage to normal tissues caused by two radiotherapy sessions at the same site. It is recommended that patients undergo both radiotherapy sessions in the same hospital to avoid the surrounding vital organs as much as possible and to minimize the side effects of radiotherapy.