摘要
目的:比较左侧乳腺癌保乳术后大分割放疗时,野中野正向调强(field-in-field intensity modulated radiation therapy,FIF-IMRT)、逆向调强(intensity modulated radiation therapy,IMRT)两种模式对改善靶区剂量分布和保护正常组织的差异。方法:对30例左侧乳腺癌保乳术后患者予以CT定位,分别制定FIF-IMRT及IMRT二种照射计划,总剂量均为42.65 Gy,共照射16次。分别比较两组计划的靶区剂量分布、危及器官,如心脏、肺脏、脊髓等所受剂量以及加速器总跳数(accelerator monitor unit,MU)的差异。结果:FIF-IMRT与IMRT组PTV(planning target volume)的D_(max)分别为4762.35 cGy(4710.08,4829.10)cGy、4714.60 cGy(4659.55,4740.85)cGy(P=0.001),均匀性指数分别为0.10(0.09,0.11)和0.09(0.08,0.10)(P=0.008);在危及器官受量方面,FIF-IMRT组较IMRT组明显降低心脏V_(5)、V_(10)和左肺V_(5)、V_(10)(P值分别为<0.001、<0.001、0.003、0.014),右乳D_(max)、D_(mean)和脊髓D_(max)、D_(mean) FIF-IMRT组均显著低于IMRT组(P值分别为0.048、0.044、<0.001、<0.001)。FIF-IMRT组MU低于IMRT组(P=0.001)。结论:两种大分割调强模式均能满足左侧乳腺癌保乳术后的治疗要求。IMRT提高靶区剂量分布均匀性,但FIF-IMRT能更好降低心脏和左肺V_(5)、V_(10)等低剂量照射范围,且对机器损耗更小,可能是更好的选择。
Objective:To compare the differences between FIF-IMRT(field-in-field intensity modulated radiation therapy)and IMRT(intensity modulated radiation therapy)in improving dose distribution in target areas and protecting normal tissues in the hypofractionated radiotherapy for left breast cancer after breast-conserving surgery.Methods:CT-based simulation was performed on 30 left breast cancer patients underwent breast-conserving surgery,followed by both FIF-IMRT and IMRT plans.The prescription dose was set as 42.56 Gy in 16 fractions.The dose distribution of target volume and normal tissues,MU(accelerator monitor unit)were compared between the two radiotherapy plan modes.Results:The D_(max) of PTV(planning target volume)in FIF-IMRT and IMRT groups were 4762.35 cGy(4710.08,4829.10)cGy,4714.60 cGy(4659.55,4740.85)cGy(P=0.001),and the uniformity index were 0.10(0.09,0.11)and 0.09(0.08,0.10)(P=0.008),respectively.The heart V_(5),V_(10) and the left lung V_(5),V_(10) in FIF-IMRT plan were significantly lower than those of IMRT plan(P<0.001,<0.001,0.003 and 0.014,respectively).The right breast D_(mean),D_(max),the spinal cord D_(mean),D_(max) and MU in FIF-IMRT plan were significantly lower than that of IMRT plan(P=0.048,0.044,<0.001,<0.001 and 0.001,respectively).Conclusion:Both FIF-IMRT and IMRT plans can meet the requirements of clinical treatments.IMRT can improve the target uniformity,but FIF-IMRT can better reduce the low-dose irradiation range of heart and left lung with less damage of the machine,which may be a better choice.
作者
周芳
刘婷
何雪平
朱惠平
孙阳
沈政洁
陈亚楠
ZHOU Fang;LIU Ting;HE Xueping;ZHU Huiping;SUN Yang;SHEN Zhengjie;CHEN Yanan(Department of Oncology,the Affiliated Zhangjiagang Hospital of Soochow University,Jiangsu Suzhou 215600,China)
出处
《现代肿瘤医学》
CAS
北大核心
2021年第15期2686-2690,共5页
Journal of Modern Oncology
基金
江苏省张家港市卫生青年科技项目(编号:ZJGQNKJ201924)。
关键词
乳腺癌
保乳术
大分割放疗
野中野正向调强
逆向调强
剂量学
breast cancer
breast-conserving surgery
hypofractionated radiotherapy
FIF-IMRT
IMRT
dosimetry
