摘要
目的:对比分析颈段或者胸上段食管癌固定野动态调强放疗(dIMRT)和容积旋转调强放疗(VMAT)的剂量学及剂量稳健性。方法:选取22例行根治性放疗的颈段或者胸上段食管癌患者为研究对象,行dIMRT和VMAT两种放疗计划。比较两种放疗计划在患者双肺、心脏、脊髓等的剂量;每种技术计划在X轴(左右)、Y轴(前后)、Z轴(头脚)6个方向各平移治疗中心3 mm模拟摆位误差重新计算靶区和危及器官剂量分布,观察靶区和危及器官剂量分布与原计划的变化。结果:两种放疗技术均能达到靶区处方剂量,靶区适形度高,靶区内剂量分布均匀;dIMRT双肺V5、V10、V15、V20、V30、Dmean,均高于VMAT(P<0.05);VMAT心脏V20、V30、V40、Dmean高于dIMRT(P<0.05)。在3 mm摆位误差引入下,并不降低靶区的处方剂量,危及器官照射剂量也在剂量限制范围内,dIMRT与VMAT靶区和周围危及器官照射剂量和照射体积变化相差不大,二者稳健性一致。结论:在危及器官,VMAT对心脏的照射剂量比dIMRT多,dIMRT对肺的照射剂量比VMAT多,但都在剂量限制范围内。dIMRT的机器跳数更少,VMAT的治疗时间更短。在X、Y、Z三个轴,左右、前后、头脚6个方向引入3 mm摆位误差时,dIMRT与VMAT剂量学参数变化均不大,稳健性一致。
Objective:To analyze and compare the differences in dosimetric parameters between two radiotherapy techniques [dynamic intensity modulated radiotherapy(dIMRT) and volumetric modulated arc radiotherapy(VMAT)] for cervical or upper thoracic esophageal cancer patients,as well as the dose robustness of dIMRT and VMAT under the introduction of 3 mm positioning error.Methods:Selected 22 patients with cervical or upper thoracic esophageal cancer who undergo radical radiotherapy to design a radiotherapy plan.Design dIMRT and VMAT radiotherapy plans simultaneously for each patient,and compare the dose differences between the two radiotherapy plans in the lungs,heart,spinal cord,and other areas.Each technology plan involved translating the treatment center in 6 directions,including the X-axis(left and right),Y-axis(front and back),and Z-axis(head and feet),with a simulated positioning error of 3 mm.The dose distribution of the target area and endangered organs was recalculated,and the changes in the dose distribution of the target area and endangered organs compared to the original plan are observed.Results:Both radiotherapy techniques were able to achieve the prescribed dose in the target area,with high conformability and uniform dose distribution within the target area.Both lungs:For V5,V10,V15,V20,V30,and Dmean,dIMRT was slightly higher than VMAT,and the difference was statistically significant(P<0.05).Heart:For V20,V30,V40,and Dmean,VMAT was slightly higher than dIMRT,and the difference was statistically significant(P<0.05).Under the introduction of 3 mm positioning error,the prescription dose in the target area was not reduced,and the radiation dose to organs at risk was also within the dose limit range.The difference in radiation dose and volume between dIMRT and VMAT target areas and surrounding organs at risk was not significant,and the robustness of the two was consistent.Conclusion:When endangering organs,VMAT has a higher radiation dose to the heart than dIMRT,and dIMRT has a higher radiation dose to the lungs,but both are within the dose limit range.DIMRT has fewer machine hops and shorter treatment time for VMAT.When introducing a 3 mm positioning error in the X,Y,and Z axes,left and right,front and back,and head and foot directions,there is little change in the dosimetric parameters of dIMRT and VMAT,and their robustness is consistent.
作者
李晓春
王锐锶
刘雪萍
谭榜宪
LI Xiao-chun;WANG Rui-si;LIU Xue-ping;TAN Bang-xian(Department of Oncology,Affiliated Hospital of North Sichuan Medical College,Nanchong 637000,Sichuan,China)
出处
《川北医学院学报》
2025年第3期370-374,共5页
Journal of North Sichuan Medical College
基金
四川省南充市市校合作科研专项(18SXHZ0413)。
关键词
食管癌
放射治疗
固定野动态调强放疗
容积旋转调强放疗
Esophageal cancer
Radiation therapy
Dynamic intensity modulated radiotherapy
Volumetric modulated arc radiotherapy
