中文摘要：

目的分析射波刀治疗肺转移瘤的疗效及安全性。方法2006--2010年间本院射波刀中心治疗的有病理诊断的肺转移瘤患者48例，治疗肺转移病灶93个。病灶中位靶体积6．0cm^3（0．2—135．2cm^3），中位生物等效剂量为140．8cGy（53—180cGy）（α/β=10），中位分割次数为3次（1—7次），中位等剂量线为81％（71％～91％）。Kaplan—Meier法计算生存率并Logrank单因素预后分析。结果随访率为96％，随访时间满2年者33例。病灶有效率为90．3％，2例患者2个病灶局部进展。1、2年局部控制率分别为98％、98％，总生存率分别为83％、63％，无进展生存率分别为64％、37％。单因素分析显示无进展生存的高龄患者（〉60岁）有好于低龄患者（≤60岁）趋势（x^2=3．45，P=0．063），单发患者优于多发患者（X^2=4．49，P=0．034）；总生存的原发确诊至转移时间〉18个月患者优于≤18个月患者（x^2=6．50，P=0．011）。不良反应为1级急性放射性损伤5例，2、3级急性放射性肺损伤各1例，皮下组织纤维化改变伴有局部皮肤色素沉着1例。结论射波刀在肺转移瘤的治疗中具有良好的近期疗效，急性不良反应轻、安全性好，远期疗效和不良反应需进一步随访。

英文摘要：

Objective To investigate the effectiveness and toxicity of CyberKnife in the treatment of lung metastases. Methods Treatment details and outcomes were reviewed for 93 targets of 48 histologically verified patients treated by CyberKnife at the CyberKnife Center of Tianjin between September 2006 and June 2010. The median tumor volume was 6. 0 （0. 2 -135.2） cmz, the median biological equivalent dose was 140. 8 （53 - 180） cGy （α/β= 10）, the median fraction was 3 （1 -7 ） times and the median isodose line was 81% （71% -91% ）. Results The rate of follow-up is 96%. 33 cases were followed up for more than 2 years. The effective rate was 90. 3%. Two targets of 2 patients locally progressed. The 1-and 2-year local control rates, overall survival （OS） rates and progression-free survival （PFS） rates were 98% and 98% , 83% and 63% ,and 64% and 37% , respectively. Univariate analyses showed that age older than 60 versus ≤ 60 years tended to be predictor for PFS （ X2 = 3.45, P = 0. 063 ） ; The PFS of patients who had single lesion was better than patients with multiple lesions （ X2 = 4. 49, P = 0. 034 ） ; patients with disease-free interval longer than 18 months had better OS （X2= 6.50,P = 0. 011 ）. Five patients were reported to experience treatment-related grade 1 radiation pulmonary injury, and one each for subcutaneous fibrosis with pigmentation, grade 2 and grade 3 adverse event. Conclusions For patients with lung metastatic lesion, CyberKnife is an effective option with high local control rate and little acute reaction. The long-term outcome and toxicity need further study.