放射治疗(radiation therapy,RT)已有上百年历史,是目前治疗肿瘤的三大疗法之一。约70%肿瘤患者的治疗会涉及放疗。该疗法在恶性肿瘤治愈率中占12%,显著优于化疗的5%。放射线只要剂量足够没有杀不死的癌细胞,但过量的放射也会致死。因此临床为减少不良反应限制放疗剂量。随着计算机技术和医学影像学的发展,各种精确放疗又得以快速发展,以减小不良反应。1放疗的弱点 Radiation therapy (RT) has been around for hundreds of years and is currently one of the three major therapies for treating cancer. About 70% of cancer patients will be treated with radiotherapy. This therapy accounts for 12% of the cure rates for malignant tumors and is significantly better than 5% of chemotherapy. As long as the radiation dose is not enough to kill dead cancer cells, but excessive radiation can also cause death. Therefore, clinically to reduce adverse reactions limit the dose of radiotherapy. With the development of computer technology and medical imaging, a variety of precise radiotherapy has been rapidly developed to reduce adverse reactions. 1 radiotherapy weakness