AlignRT在乳腺癌术后放疗体表引导摆位中感兴趣区优选  

Determining the optimal region of interest for AlignRT-guided positioning in postoperative radiotherapy for breast cancer

作　　者：李俊禹 杨敬贤[1] 于松茂 卢子红 周舜 陈吉祥[1] 王振飞 丁大庆 王美娇[1] 杜乙 LI Junyu;YANG Jingxian;YU Songmao;LU Zihong;ZHOU Shun;CHEN Jixiang;WANG Zhenfei;DING Daqing;WANG Meijiao;DU Yi(Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing)/Department of Radiation Oncology,Peking University Cancer Hospital&Institute,Beijing 100142,China)

机构地区：[1]北京大学肿瘤医院暨北京市肿瘤防治研究所放疗科/恶性肿瘤发病机制及转化研究教育部重点实验室,北京100142

出　　处：《中国医学物理学杂志》2023年第1期1-6,共6页Chinese Journal of Medical Physics

基　　金：北京市自然科学基金(1212011);国家自然科学基金(12005007);北京大学肿瘤医院科学研究基金(2021-14,KC2204);国家重点研发计划(2019YFF01014405)。

摘　　要：目的:光学体表追踪系统AlignRT引导乳腺癌术后放疗摆位中,通过对比3种典型感兴趣区(ROI)AlignRT与CBCT误差之间摆位一致性差异,确定临床最优ROI勾画范围。方法:回顾性分析33例利用AlignRT引导摆位的乳腺癌患者病例数据,摆位结束后记录197次CBCT同分次下全胸、患侧乳腺和胸部刚性3种ROI的AlignRT误差数据,CBCT与定位CT进行基于脊柱6维配准靶区微调后,获得6维CBCT误差,AlignRT与CBCT误差差值绝对化后用于量化摆位一致性,比较全胸、患侧乳腺和胸部刚性这3组ROI的AlignRT误差及摆位一致性差异。结果:AlignRT引导摆位CBCT误差线性方向/旋转方向在±0.50 cm/±2.0°之间的占比为99.92%。全胸、患侧乳腺、胸部刚性3组ROI的AlignRT误差在Pitch(P<0.001)、Roll(P=0.002)方向差异有统计学意义。全胸ROI在x、Rtn、Pitch和Roll方向摆位一致性均优于患侧乳腺和胸部刚性ROI,x(P=0.001)、Rtn(P<0.001)、Roll(P=0.001)方向差异有统计学意义,Pitch(P=0.541)方向差异无统计学意义。结论:本中心基于AlignRT引导乳腺癌术后放疗摆位流程使CBCT误差均满足临床要求。包括双侧乳腺/胸壁、胸骨、肋骨和锁骨的全胸ROI摆位一致性整体优于患侧乳腺和胸部刚性ROI,应作为乳腺癌术后放疗AlignRT引导摆位首选ROI勾画范围。Objective To determine the optimal breast region of interest(ROI)among 3 typical suggested ROI for AlignRT-guided positioning in postoperative radiotherapy for breast cancer by comparing the positioning consistency between AlignRT errors and CBCT errors.Methods The clinical data of 33 cases of breast cancer patients undergoing AlignRT-guided positioning were analyzed retrospectively.After positioning,the AlignRT errors of 3 ROI,namely the whole chest region,the ipsilateral breast region,and the chest rigid region,were recorded for 197 CBCT.The registration results of CBCT and the positioning CT were fine-tuned based on the spine's 6-dimensional registration target area,and the 6-dimensional CBCT errors were obtained.The absolute values of the differences between AlignRT errors and CBCT errors were used to quantify the positioning consistency.The AlignRT errors and positioning consistency in 3 different groups were compared.Results The proportion of deviations in linear directions(within 0.5 cm)/rotation directions(within 2.0°)of CBCT data in AlignRT-guided positioning was 99.92%.There were statistically significant differences in AlignRT errors in the Pitch(P<0.001)and Roll(P=0.002)directions among 3 ROI groups.The whole chest region as an optimal breast ROI in patient setup consistency shows a superiority than ipsilateral breast region and the chest rigid region in x(P=0.001),Rtn(P<0.001),Pitch(P=0.541)and Roll(P=0.001)directions.Conclusion The usage of AlignRT as a breast radiotherapy positioning guide tool to minimize the patient positioning errors in CBCT satisfied clinical requirements.The positioning consistency using the whole chest region(including bilateral breast/chest wall,sternum,ribs and clavicle)as the optimal ROI has proven its suitability than ipsilateral breast region and the chest rigid region.The whole chest region as the benchmark for scanning region in AlignRT system is the optimal ROI in postoperative radiotherapy for breast cancer.

关 键 词：乳腺肿瘤 光学体表追踪系统 感兴趣区 摆位误差 

分 类 号：R737.9[医药卫生—肿瘤] R811.1[医药卫生—临床医学]