增强扫描对基于4DCT胸段食管癌GTV勾画及IGTV构建的影响  

Impact of contrast-enhanced 4DCT scan on delineating GTV and constructing IGTV in thoracic esophageal cancer

作　　者：王金之[1] 李建彬[1] 戚焕鹏[2] 张英杰[1] 王玮[1] 马志芳[1] 丁昀[3] 尚东平[1] 

机构地区：[1]山东省肿瘤医院放疗科,济南250117 [2]泰安市肿瘤防治院 [3]常州市第一人民医院

出　　处：《中华放射肿瘤学杂志》2015年第2期116-120,共5页Chinese Journal of Radiation Oncology

基　　金：山东省科技发展计划项目（2011YD18039）;山东省科技发展计划项目（2011YD18082）

摘　　要：目的 探讨增强扫描与否对基于4DCT勾画的胸段食管癌原发肿瘤各时相GTV差异及对IGTV构建的影响.方法 25例胸段食管癌患者,胸上段8例、胸中段9例、胸下段8例,自由呼吸状态下序贯完成普通4DCT与增强4DCT扫描,同一勾画者按照同一标准先在平扫4DCT各图像上勾画GTV并构建相应IGTV.1个月后同一勾画者再在增强4DCT图像上勾画GTV并构建相应IGTV.结果 基于增强扫描图像勾画的靶区变异系数小于平扫图像勾画的（P=0.000）,但胸上、下段食管癌患者二者的GTVz轴长度、GTV、IGTV均相近（P=0.529、0.110;P=0.158、0.416;P=0.147、0.615）,而对胸中段食管癌患者二者的GTV z轴长度、GTV、IGTV不同（P=0.005、0.035、0.021）.结论 对胸中段食管癌患者,增强4DCT扫描可减小靶区勾画误差并可构建相对精确的IGTV,而对胸上、下段食管癌患者靶区勾画及IGTV构建无显著影响.Objective To investigate the difference between conventional and contrast-enhanced four-dimensional computed tomography （4DCT） scans in delineating the gross tumor volume （GTV） in different phases and constructing the internal gross tumor volume （IGTV） in primary thoracic esophageal cancer.Methods Twenty-five patients with thoracic esophageal cancer,including 8 upper-thoracic,9 middle-thoracic,and 8 lower-thoracic,sequentially underwent conventional and contrast-enhanced 4DCT scans during normal breathing.The GTVs were delineated by a physician under the same standard using conventional plain 4DCT images,and the IGTVs were constructed accordingly.After one month,the GTVs were delineated by contrast-enhanced 4DCT images and IGTVs were constructed by the same physician.Results The coefficient of variation for the target volume based on the contrast-enhanced 4DCT images was smaller than that based on the plain 4DCT images.There were no significant differences in the length of the z axis of GTV,GTV,and IGTV between contrast-enhanced and plain 4DCT images in patients with upperand lower-thoracic esophageal cancer （P =0.529 and 0.110 ;P =0.158 and 0.416 ;P =0.147 and 0.615）.However,in patients with middle-thoracic esophageal cancer,the length of the z axis of GTV,GTV,and IGTV were significantly different between contrast-enhanced and plain 4DCT images （P =0.005,0.035,and 0.021,respectively）.Conclusions Contrast-enhanced 4DCT scan can reduce the error in delineating the target volume and construct a more accurate IGTV for patients with middle-thoracic esophageal cancer.However,it has no significant benefit in patients with upper-and lower-thoracic esophageal cancer.

关 键 词：体层摄影术 X线计算机 四维 大体肿瘤体积 变异系数 食管肿瘤/放射疗法 

分 类 号：R735.1[医药卫生—肿瘤]