伽马刀SBRT与直线加速器SBRT治疗肺部肿瘤的剂量学对比研究  

Dosimetric comparison between gamma knife SBRT and linear accelerator⁃based SBRT for lung tumors

作　　者：段文越 吴华健 赵耿昊 张传豪 范治军 王喆[1] 王若雨[1] Duan Wenyue;Wu Huajian;Zhao Genghao;Zhang Chuanhao;Fan Zhijun;Wang Zhe;Wang Ruoyu(Department of Medical Oncology,Affiliated Zhongshan Hospital of Dalian University,The Key Laboratory of Biomarker High Throughput Screening and Target Translation of Breast and Gastrointestinal Tumor,The Key Laboratory of Radioactive Particles and Thermal Precision Therapy,Dalian University,Dalian 116001,China;Graduate School of Dalian Medical University,Dalian 116044,China)

机构地区：[1]大连大学附属中山医院肿瘤中心辽宁省乳腺及消化肿瘤分子标志物高通量筛选及靶向药物转化重点实验室辽宁省放射性粒子及热精准治疗重点实验室,大连116001 [2]大连医科大学研究生院,大连116044

出　　处：《中华放射医学与防护杂志》2024年第6期482-488,共7页Chinese Journal of Radiological Medicine and Protection

基　　金：辽宁省科学技术计划项目(2021JH1/10400051);大连市高端人才项目(2021RD02);国家重点研发计划(2022YFC2407104)。

摘　　要：目的比较分析伽马刀立体定向放射治疗(SBRT)与基于直线加速器的X射线SBRT治疗肺部肿瘤的剂量学差异,为治疗策略的选择提供理论依据。方法选取2022年1月至2023年5月在大连大学附属中山医院肿瘤中心接受肺部SBRT的患者7位,针对其13个病灶,分别设计伽马刀SBRT(γ_SBRT)计划与加速器SBRT(X_SBRT)计划,将同一患者位置邻近的病灶设计在同一计划中,得到γ_SBRT与X_SBRT计划各10个,处方剂量为30~50 Gy/5~10次。比较分析两种计划的剂量参数,包括:计划靶区(PTV)的靶区覆盖率,梯度指数(GI),适形指数(CI),最大剂量(D_(max)),平均剂量(D_(mean)),最小剂量(D_(min));20 Gy(V_(20))、10 Gy(V_(10))、5 Gy(V_(5))剂量线包绕的体积,100%处方剂量(V_(100%))、50%处方剂量(V_(50%))剂量线包绕的体积;患侧肺D_(mean)、20 Gy剂量线包绕的肺体积占该侧肺体积的百分比(Lung_V_(20))、5 Gy剂量线包绕的肺体积占该侧肺体积的百分比(Lung_V_(5)),健侧肺D_(mean)、Lung_V_(5),食管、脊髓以及心脏的D_(max)。结果γ_SBRT计划在GI,V_(20)、V_(10)、V_(5)、V_(50%),患侧肺D_(mean)、Lung_V_(20)、Lung_V_(5),健侧肺D_(mean)、Lung_V_(5),以及食管和心脏D_(max)方面均优于X_SBRT计划(z=-2.81~-1.99,P<0.05)。γ_SBRT计划中,PTV的D_(max)以及D_(mean)高于X_SBRT计划(z=-2.80、-2.80,P<0.05);靶区覆盖率、CI、脊髓D_(max)在二者间差异无统计学意义(P>0.05);γ_SBRT计划的治疗时间长于X_SBRT计划(z=-2.70,P<0.05)。结论伽马刀SBRT计划在靶区外剂量跌落方面优于加速器SBRT计划,在肺部肿瘤治疗中有望减少靶区周围低剂量区以及正常肺组织受照剂量,但治疗时间显著增加。Objective To analyze the dosimetric differences between gamma knife stereotactic body radiation therapy(SBRT)and linear accelerator⁃based SBRT for lung tumors by comparison to provide a theoretical basis for the selection of treatment strategies.Methods Seven patients who underwent SBRT for lung tumors in the Cancer Center of Affiliated Zhongshan Hospital of Dalian University from January 2022 to May 2023 were enrolled.Plans of gamma knife SBRT(γ_SBRT)or linear accelerator⁃based SBRT plans(X_SBRT)were designed for the 13 lesions in the patients,with adjacent lesions in the same patient sharing one plan.As a result,10γ_SBRT plans and 10 X_SBRT plans were obtained.All lesions received 30-50 Gy of radiation in 5-10 fractions.Then,dosimetric parameters were analyzed and compared betweenγ_SBRT and X_SBRT plans,including the target coverage,gradient index(GI),conformity index(CI),maximum dose(D_(max));mean dose(D_(mean)),and minimum dose(Dmin)of planning target volumes(PTVs);lung volumes receiving 20 Gy or more(V_(20)),10 Gy or more(V_(10)),5 Gy or more(V_(5)),100%of the prescription dose(V_(100%)),and 50%of the prescription dose(V_(50%));D_(mean)and the percentages of lung volume receiving doses of 20 Gy or more(Lung_V_(20))and 5 Gy or more(Lung_V5)of ipsilateral lung;D_(mean)and Lung_V_(5)of contralateral lung;and D_(max)values of the esophagus,spinal cord,and heart.Results Compared to X_SBRT plans,γ_SBRT plans exhibited superior GI,V_(20),V_(10),V_(5),V_(50%),the D_(mean),Lung_V_(20),and Lung_V_(5)of ipsilateral lung,the D_(mean)and Lung_V_(5)of the contralateral lung,and the D_(max)of esophageal and heart(z=-2.81 to-1.99,P<0.05),higher D_(max)and D_(mean)of PTVs(z=-2.80,-2.80,P<0.05),and longer delivery time(z=-2.70,P<0.05).Meanwhile,there was no significant difference in target coverage,CI,and D_(max)of the spinal cord(P>0.05).Conclusions Gamma knife SBRT plans can achieve sharper dose falloff outside target volumes than linear accelerator⁃based SBRT plans.Gamma knife radiosurgery is expected to reduce t

关 键 词：立体定向放射治疗 伽马刀 肺部肿瘤 剂量分布 

分 类 号：R734.2[医药卫生—肿瘤]