千伏锥形束CT(kV-CBCT)图像引导宫颈癌放射治疗的三维摆位误差分析  

Three-dimensional positioning error analysis of image-guided radiation therapy for cervical cancer using kilovoltage cone-beam computed tomography

作　　者：朱清红 陈小君[1] 甘庆权[1] ZHU Qinghong;CHEN Xiaojun;GAN Qingquan(Department of Oncology,Guangzhou First People's Hospital,Guangzhou 510180,China)

机构地区：[1]广州市第一人民医院肿瘤科,广州510180

出　　处：《广州医药》2021年第5期113-116,121,共5页Guangzhou Medical Journal

摘　　要：目的利用高精确的外照射治疗技术,即图像引导放射治疗/容积旋转调强放疗(IGRT/VMAT)时,使用千伏锥形束CT(kV-CBCT)定位来获得最佳的宫颈癌治疗获益。方法205例接受IGRT/VMAT治疗的宫颈癌患者纳入实验组。每周做一次kV-CBCT定位后,将这些图像与计划CT扫描图像匹配后记录摆位误差。总共研究了1025个kV-CBCT图像。采取同时期常规X片定位的90例宫颈癌患者作为对照组。根据定位中的摆位误差计算计划靶区(PTV)的边界。结果实验组前后、上下和左右方向的摆位误差分别为(1.8±1.1)mm、(2.8±2.2)mm和(1.7±1.4)mm,对照组分别为(2.8±2.1)mm、(3.9±2.2)mm和(2.7±2.4)mm,两组差异具有统计学意义(P<0.05)。实验组前后、上下和左右方向的CTV-PTV边界分别为5.27 mm、8.54 mm和5.23 mm,对照组分别为8.47 mm、11.29 mm和8.43 mm。结论在采用高精度技术治疗宫颈癌时,每周kV-CBCT是一种令人满意的精确定位方法,有助于减少CTV-PTV边界。Objective To obtain the best cervical cancer treatment benefit through kilovoltage cone-beam CT(kV-CBCT)positioning,by using high-precision external beam therapy technology,that is,image-guided radiation therapy/volumetric modulated arc therapy(IGRT/VMAT).Methods Two hundred and five patients with cervical cancer treated with IGRT/VMAT were included in the experimental group.After kV-CBCT positioning once a week,these images were matched with the planned CT scan images and the setup errors were recorded.A total of 1025 kV-CBCT images were studied.Ninety patients with cervical cancer positioned by conventional X-ray during the same period were selected as the control group.The boundary of the planned target volume(PTV)was calculated based on the setup errors.Results In the experimental group,the setup errors in the anteroposterior,superoinferior and mediolateral direction were(1.8±1.1)mm,(2.8±2.2)mm,and(1.7±1.4)mm,respectively.And in the control group,the setup errors were(2.8±2.1)mm,(3.9±2.2)mm,and(2.7±2.4)mm,respectively.The differences between the two groups were statistically significant(P<0.05).In the experimental group,the CTV-PTV boundaries in the anteroposterior,superoinferior and mediolateral direction were 5.27 mm,8.54 mm,and 5.23 mm,respectively.And in the control group,the CTV-PTV boundaries were 8.47 mm,11.29 mm,and 8.43 mm,respectively.Conclusion When using high-precision technology to treat cervical cancer,weekly kV-CBCT is a satisfactory and accurate positioning method,which helps to reduce the CTV-PTV boundary.

关 键 词：宫颈癌 影像引导 千伏锥形束CT 边界 摆位误差 

分 类 号：R730.55[医药卫生—肿瘤] R737.33[医药卫生—临床医学]