摘要
目的:比较肺癌三维适形放射治疗与常规放射治疗时的肿瘤靶区、正常组织和器官的剂量分布优势。方法:选择三维适形放射治疗进行根治性治疗的10例肺癌,先在适形放射治疗体位下在模拟机下常规定位,标出其射野范围后进行CT模拟扫描。非小细胞肺癌在DT40Gy时行第2次CT扫描调整CTV,常规照射设野避开脊髓加量。采用三维适形治疗计划系统评价常规照射和三维适形照射对肿瘤靶区、正常组织和器官的剂量分布。结果:三维适形放射治疗比常规放射治疗,从剂量分布对肿瘤靶区有更好的适形度,95%CTV达到的平均剂量高出11.5Gy(5~20Gy),平均高出医生给予剂量CTV体积的38%(10%~59%)。在正常组织中,除健侧肺的V20和V30比常规放疗稍高外(1.1%和1.7%),脊髓的最大剂量平均低4Gy(-4~12Gy),心脏V35低24.3%(-4%~75%),双肺V20和V30分别低7%(-5%~20%)与7.4%(-6%~20%),患侧肺的V20和V30分别低13%(-7%~45%)和15%(-8%~40%)。结论:三维适形放疗治疗肺癌比常规放射治疗有一定的优势,对肿瘤靶区有更好的适形度和剂量均匀性,并且能更好的减少正常组织脊髓、心脏和肺的照射体积和剂量,特别是高剂量的照射体积。
Objective:To compare the dosiology of three-dimensional conformal radiotherapy (3D-CRT)and conventional radiotherapy (RT) in the patients with lung cancer. Methods:Ten patients with lung cancer given radical treatment by 3D-CRT were entered into the study. Before CT-simulate scan,conventional irradiation fields were carried on simulator with immobilization device. 3D-CRT plans and conventional radiotherapy plans were performed for each patient. Doses distributions and DVH for tumors (CTV) and normal tissue in both plans were compared. Results:Comparing 3D-CRT and conventional RT,the volume of the prescription doses of 3D-CRT was 38% higher than conventional RT( 10% -59% ), the doses in 95% CTV of 3D-CRT were 11.5Gy more than in conventional RT(5 -20Gy), The spinal cord doses,the volume of heart V35, the volume of lung V20 and V30 of 3D-CRT were 4Gy,24. 3% ,7% and 7.4% , respectively, including that the volume of sick lung V20 and V30 of 3D-CRT were 13% and 15%. The volume of non-affected lung of 3D-CRT was 1.1% - 1.7% higher than that with conventional RT. Conclusion :Three-dimensional conformal radiotherapy could reduce the volume of nomal tissue irradiated comparing with conventional radiotherapy. So 3D-CRT could protect normal tissue better.
出处
《临床肿瘤学杂志》
CAS
2006年第11期814-817,821,共5页
Chinese Clinical Oncology
基金
首都医学发展基金资助项目(2002-3009)
关键词
肺肿瘤
放射治疗
剂量分布
放射物理
适形放射治疗
Lung neoplasma
Radiotherapy
Dose distribution
Radiophysics
Three-dimensional conformal radiotherapy