锥形束CT(CBCT)在中下段食管癌患者放射治疗中的价值分析  

Evaluation of Cone Beam CT(CBCT)in Radiotherapy for Patients with Middle and Lower Esophageal Cancer

作　　者：朱均强[1] 孙绍涵 班卫华[3] 苏善宁 吕伟 庞林 Zhu Junqiang;Sun Shaohan;Ban Weihua;Su Shanning;Lui Wei;Pang Lin(Department of Radiation Oncology,Red Cross Hospital of Yulin City,Yulin 537000,Guangxi,China;Radiation Therapy Center,Wuming Hospital of Guangxi Medical University,Nanning 530100,Guangxi,China;Department of Radiation Oncology,Baise People's Hospital,Baise 533000,Guangxi,China)

机构地区：[1]玉林市红十字会医院放疗科,广西玉林537000 [2]广西医科大学附属武鸣医院放疗中心,南宁530100 [3]百色市人民医院放疗科,广西百色533000

出　　处：《肿瘤预防与治疗》2025年第3期224-230,共7页Journal of Cancer Control And Treatment

基　　金：广西壮族自治区卫健委自筹经费科研课题(编号:Z20180443);玉林市科学研究与技术开发计划项目(编号:[玉市科]20220609)。

摘　　要：目的:本研究旨在探讨锥形束CT(cone beam computed tomography,CBCT)在中下段食管癌放射治疗中的应用价值,为临床应用提供参考。方法:回顾性选取中下段食管癌患者共101例,在体表做好十字标记线,定位时双手交叉抱肘置于额前并用体膜固定。首次和之后每1周放射治疗前采集1次CBCT图像,并与定位CT影像匹配,获取患者左右(X轴)、头脚(Y轴)、前后(Z轴)和治疗床旋转角度θ4个方向的误差。分析摆位误差及其分布情况,并用公式计算临床靶区到计划靶区的外扩范围。结果:共拍CBCT 224次。整体X、Y、Z和θ方向的摆位误差为(-0.02±0.20)cm、(0.05±0.25)cm、(0.03±0.16)cm和(-0.03±0.64)°,X、Y和Z方向差异有统计学意义(F=7.537,P=0.001),X、Y方向和X、Z方向差异有统计学意义(P<0.001,P=0.013)。整体X、Y、Z方向的外扩范围分别为0.46 cm、0.63 cm、0.40 cm。与第一周摆位误差相比,X方向第4周误差均值增大0.05 cm,Z方向第5周误差均值减小0.04 cm,差异有统计学意义(P=0.024,P=0.016)。结论:对于中下段食管癌患者,应用CBCT可以方便分析摆位误差,有效规范临床靶区到计划靶区的外扩范围,并可以指导技师摆位,有效减小患者摆位误差,提高放射治疗精准度。Objective:To investigate the application value of cone beam computed tomography(CBCT)in radiotherapy for middle and lower esophageal cancer and to provide evidence for clinical practice.Methods:A total of 101 patients with middle and lower esophageal cancer were retrospectively enrolled.During positioning,a crossline was marked on the body surface,and patients were instructed to cross their arms and place their elbows in front of their forehead,secured with a body membrane.CBCT images were acquired at the first treatment session and weekly thereafter.These images were matched with the planning CT images to determine setup errors in the left-right(X-axis),superior-inferior(Y-axis),and anterior-posterior(Z-axis)directions,as well as the treatment couch rotation angleθ.The setup errors were analyzed,and the planning target volume(PTV)margins were calculated using a standard formula.Results:A total of 224 CBCT images were obtained.The overall setup errors in the X,Y,and Z directions and the rotation angleθwere(-0.02±0.20)cm,(0.05±0.25)cm,(0.03±0.16)cm,and(-0.03±0.64)°,respectively.The differences in setup errors among the X,Y,and Z directions were statistically significant(F=7.537,P=0.001).Pairwise comparisons revealed statistically significant differences between the X and Y directions(P<0.001)and between the X and Z directions(P=0.013).The calculated PTV margins in the X,Y,and Z directions were 0.46 cm,0.63 cm,and 0.40 cm,respectively.Compared with the first week,the mean setup error in the X direction increased by 0.05 cm in the fourth week,while the mean setup error in the Z direction decreased by 0.04 cm in the fifth week,both of which were statistically significant(P=0.024 and P=0.016,respectively).Conclusion:For patients with middle and lower esophageal cancer,the application of CBCT enables accurate analysis of setup errors,standardizes PTV margins effectively,guides therapists in patient setup,reduces setup errors,and improves the precision of radiotherapy.

关 键 词：中下段食管癌 锥形束CT 调强放射治疗 摆位误差 外扩范围 

分 类 号：R735.1[医药卫生—肿瘤] R815.6[医药卫生—临床医学]