射波刀-低分割单次大剂量立体定向放射治疗的最佳执行者

Cyberknife,the Best Choice for High Fractional Dose Radiation Therapy

常规放疗模式沿用多年，肿瘤治愈率难以得到大的突破。放疗总剂量与肿瘤预后直接相关，按照放射生物学推断的肿瘤治疗剂量明显高于目前常规放疗模式的放射总剂量。生物有效剂量与局控率和生存率有显著相关性，其提高依赖于单次剂量的提高。短疗程高分次剂量的放射治疗模式主要通过立体定向适形放疗实现。目前立体定向放射治疗装置单次放射剂量提高至4—8Gy，但是治疗精度无法进一步提高。射渡刀在固定方式、实时位置验证、影像引导及动态追踪病灶等方面具有明显的技术优势，单次放射剂量能够提高至15～30Gy，成为短疗程单次高剂量放疗模式的最佳执行者，治疗效果更好。射波刀高分次剂量短疗程放疗模式本身在很多方面有待完善发展。

Conventional radiotheraphy has been used for many years and its tumor control rate is hard to be raised. Accumulated dose is directly related to prognosis. According to radiobiology, the radiation dose for tumor cure is obviously higher than accumulated dose in conventional radiotheraphy. Biological effective dosage is correlated with local control rate and survival rate. Now therapeutic system of stereotactic radiation therapy can raise fractional dose to 4-8Gy. Cyberknife has obvious technical advantages in fixed mode, re- al-time position validation, image-guiding and dynamic tracing. Its fractional dose can raise to 15-30Gy, with satisfactory clinical effect. So at present, cyberknife is the best choice for high fractional dose radiation therapy.