体表铅点标记辅助iSCOUT图像引导定位系统在乳腺癌术后调强放疗应用研究  

Study of setup error and dosimetry of postoperative intensity-modulated radiotherapy for breast cancer using skin lead marker and iSCOUT image-guided positioning system

作　　者：董芳芬 戴立言[3] 黄妙云 翁星[2] 江柳清 徐本华 李小波 Dong Fangfen;Dai Liyan;Huang Miaoyun;Weng Xing;Jiang Liuqing;Xu Benhua;Li Xiaobo(College of Medical Technology and Engineering,School of Clinical Medicine,Cancer Center,Fujian Medical University,Fuzhou 350122,China;Department of Radiotherapy,Fujian Medical University Union Hospital,Fuzhou 350001,China;Department of Radiotherapy,Renji Hospital Affiliated to Shanghai Jiao Tong University Medical School,Shanghai 200025,China;Department of Engineering Physics,Tsinghua University,Beijing 100084,China)

机构地区：[1]福建医科大学医学技术与工程学院福建医科大学临床医学部福建医科大学肿瘤中心,福州350122 [2]福建医科大学附属协和医院放疗科,福州350001 [3]上海交通大学医学院附属仁济医院放疗科,200025 [4]清华大学工程物理系,北京100084

出　　处：《中华放射肿瘤学杂志》2021年第10期1059-1064,共6页Chinese Journal of Radiation Oncology

基　　金：福建省科技厅高校产学研项目(2020Y4010);福建医科大学启航基金一般项目(2020QH1078)。

摘　　要：目的探究体表铅点标记辅助iSCOUT图像引导定位系统在乳腺癌调强放疗摆位误差监测及校正的应用价值,并计算PTV外放边界为临床提供参考。方法选取2019年间福建医科大学附属协和医院行乳腺癌改良根治术后调强放疗的25例患者,利用体表铅点标记辅助iSCOUT系统基于金标配准算法进行图像引导定位,分别记录3个平移方向左右(x)、头脚(y)和腹背(z)的初始摆位误差以及图像引导校正后的残余误差统计分析,进一步比较图像引导校正前后误差对计划剂量的影响,最后计算合理的计划靶体积(PTV)外放边界。结果25例患者在体表铅点标记辅助iSCOUT图像引导定位下进行150次摆位验证,x、y、z轴向残余摆位误差绝对值分别为(1.53±0.96)、(1.30±0.99)、(1.34±0.92)mm,均小于初始误差值的(2.63±2.12)、(2.41±2.45)、(3.07±2.77)mm(P<0.001)。残余误差导致的剂量偏差百分比也比初始误差的小,在PTV的D98%、D2%、D_(max),心脏D_(max)、健侧乳腺D_(max)、患侧肺及双肺D_(mean)等具有显著差异,与原计划偏差百分比分别由2.18%、3.19%、10.66%、8.75%、48.21%、10.50%、3.66%降低到0.38%、0.23%、2.31%、0.04%、13.78%、6.35%、0.41%(P<0.05)。图像引导后PTV外放边界估算得x、y、z轴向外放边界分别为1.87、1.75、1.69 mm。结论体表铅点标记辅助iSCOUT图像引导定位系统在乳腺癌放疗体位验证及校正中的应用具有可行性和应用价值,且为临床PTV外放边界提供新的参考。Objective To explore the application value of skin lead marker combined with iSCOUT image-guided positioning system in monitoring and correcting the setup error of intensity-modulated radiotherapy(IMRT)for breast cancer and calculate the PTV margin,aiming to provide reference for clinical practice.Methods 25 breast cancer patients treated with IMRT after modified radical mastectomy in Fujian Medical University Union Hospital from April to August 2019 were enrolled in this study.The skin lead marker combined with iSCOUT image-guided positioning system was employed for image-guided positioning based on the gold standard registration algorithm.Initial setup errors on the x(lateral),y(craniocaudal)and z(anteroposterior)axis and residual errors after the position correction were recorded and analyzed.The effect of the errors before and after image-guided correction upon the plan dose was compared and the reasonable PTV margin was calculated.Results 25 patients received 150 times of positioning verification using skin lead marker combined with iSCOUT image-guided positioning system.The absolute residual errors on the x-,y-and z-axis were(1.53±0.96),(1.30±0.99)and(1.34±0.92)mm,significantly smaller than the initial setup errors of(2.63±2.12),(2.41±2.45)and(3.07±2.77)mm(all P<0.001).The percentage of dose deviation due to residual errors was also smaller than that of the initial errors.Significant differences were observed in D98%,D2%,D_(max) of PTV,D_(max) of the heart,D_(max) of the healthy breast,and D_(mean) of the affected lung and both lungs.The percentage deviation from the original plan was decreased from 2.18%,3.19%,10.66%,8.75%,48.21%,10.50%,and 3.66%to 0.38%,0.23%,2.31%,0.04%,13.78%,6.35%and 0.41%,respectively(all P<0.05).PTV margins on the x-,y-and z-axis after correction were calculated as 1.87,1.75 and 1.69 mm,respectively.Conclusion It is feasible and valuable to apply the skin lead marker combined with iSCOUT image-guided positioning system in the positioning verification and correction of breast ca

关 键 词：体表铅点标记 iSCOUT系统 乳腺肿瘤/放射疗法 摆位误差 外放边界 

分 类 号：R737.9[医药卫生—肿瘤]