适形结合调强放疗在胸中段食管癌中对正常组织受量的影响  

Affect on the normal tissues by three dimensional conformal radiation combined with intensity-modulated radiotherapy for middle esophageal carcinoma

作　　者：蒋朝阳[1] 李小凯[1] 张伶[1] 王岩松[1] 潘兴国[1] 咸婧[1] 

机构地区：[1]成都军区总医院肿瘤诊治中心放疗科,四川成都610083

出　　处：《现代肿瘤医学》2014年第5期1171-1174,共4页Journal of Modern Oncology

摘　　要：目的:比较适形结合调强放疗与单纯调强放疗在胸中段食管癌放疗中的正常组织剂量分布情况,为临床食管癌放疗计划的选择提供参考。方法:选择36例胸中段食管癌患者进行CT定位扫描。由主治及以上医师勾画出放疗靶区,设计两组放疗方案。A组为调强与适形放疗相结合的方式(其中适形放疗10次,调强放疗20次);B组为单纯的调强放疗(30次)。最后以95%PTV体积获得60Gy处方剂量进行剂量归一,利用剂量体积直方图(DVH)对以上两组计划进行下列参数的比较。两侧肺分别受量为5Gy、10Gy、15Gy、20Gy、25Gy、30Gy、35Gy、40Gy、50Gy及肺部平均受量Vlung时的体积值;心脏受量为20Gy、30Gy、40Gy、50Gy及心脏平均受量Vheart时的体积值;脊髓最大点受量。结果:A组肺部除V40及V50外,其余各组数据均较B组降低。A组心脏受量仅V40及V50较B组增加,显示有统计学差异(P≤0.007)。A组脊髓最大点受量较B组增加(P<0.05)。结论:食管癌的放疗计划中,使用调强与适形结合的方式,可以在基本不增加心脏和脊髓受量的同时有效减少肺低剂量区受照射体积。Objective：To study the selection of 3D - CRT in combination with IMRT by comParing the dose distri-bution in the middle esoPhageal cancer Patients. Methods：Thirty - six Patients of middle esoPhageal cancer receive the CT Positioning. Designed two grouPs of radiotheraPy Plan：GrouP A for 3D - CRT in combination with IMRT（re-sPectively 10 fractions and 20 fractions）,IMRT for B grouP（30 fractions）,and finally after normalizing the 60Gy Pre-scriPtion dose attained by 95% of the PTV volume. ComPare the dose volume histogram（DVe）. The volumes of the lungs when given 5Gy,10Gy,15Gy,20Gy,25Gy,30Gy,35Gy,40Gy,50Gy and mean lung dose（Vlung ）,the resPective volume of heart when given 20Gy,30Gy,40Gy,50Gy and mean heart dose（Vheart ）,the maximum dose of sPinal cord. Results：Besides V40 and V50 in grouP A,the rest were reduced comPared with grouP B. The volumes of heart in grouP A only V40 and V50 were statistically significant comPared with grouP B（P≤0. 007）. The maximum dose of sPinal cord in grouP A increased comPared with grouP B（P≤0. 05）. Conclusion：Choosing 3D - CRT in combination with IMRT can diminish effectively the area irradiated by low dose in lungs while nearly no increase of the dimensions affected by the irradiation in hearts and sPinal cord.

关 键 词：食管癌 放射疗法 调强放疗 三维适形放疗 剂量分布 

分 类 号：R735.1[医药卫生—肿瘤]