放射治疗是肿瘤治疗不可缺少的重要手段之一。随着医疗卫生事业的不断发展 ,并适应肿瘤放射治疗需求的增长 ,近些年我国放射肿瘤学事业发展很快。放射治疗的医疗照射不可能像Ｘ射线诊断的医疗照射那样有高的应用频率和相对低得多的剂量。但其主要目的是治疗癌症 ,旨在通过对准? Radiation therapy is one of the most important means of cancer treatment. With the continuous development of medical and health services, and to meet the growing demand for radiation oncology, radiation oncology in China has developed rapidly in recent years. Radiation-treated medical radiation can not have as high a frequency of application and a much lower dose as medical radiation for X-ray diagnosis. But its main purpose is to treat cancer, aimed at alignment?