非均整模式与均整模式下乳腺癌保乳术后调强放疗的剂量学研究  

Dosimetry Study of Intensity Modulated Radiotherapy After Breast Conserving Surgery Under Flattening Filter Free(FFF)Mode and Flattening Filter(FF)Mode

作　　者：唐华南 王磊 傅玉川 周莉[1] 付波 TANG Huanan;WANG Lei;FU Yuchuan;ZHOU Li;FU Bo(Radiotherapy Physics&Technology Center,Cancer Center,West China Hospital,Sichuan University,Chengdu Sichuan 610041,China;Department of Radiation Oncology,The Second Affiliated Hospital of Chengdu Medical College(Nuclear Industry 416 Hospital),Chengdu Sichuan 610051,China)

机构地区：[1]四川大学华西医院肿瘤中心放射物理技术中心,四川成都610041 [2]成都医学院第二附属医院·核工业四一六医院肿瘤科,四川成都610051

出　　处：《中国医疗设备》2023年第3期45-50,共6页China Medical Devices

基　　金：四川省科技计划重点研发项目(2020YFS0274)。

摘　　要：目的比较直线加速器6 MV X射线非均整模式(Flattening Filter Free,FFF)和均整模式(Flattening Filter,FF)下乳腺癌保乳术后调强放疗计划(Intensity Modulated Radiotherapy,IMRT)的剂量学差异和皮肤受照剂量。方法选取42例乳腺癌保乳术后放疗患者,分别设计IMRT-FFF和IMRT-FF计划。在满足临床要求的情况下,比较两组计划的靶区和感兴趣区的剂量学参数、计划机器跳数(Monitor Units,MU)和出束时间。结果左侧乳腺癌计划中,IMRT-FFF模式下靶区的V_(95%)和适形指数优于IMRT-FF模式(P<0.05);右侧乳腺癌计划中,IMRT-FFF模式下靶区的V_(95%)优于IMRT-FF模式(P<0.05),其他靶区参数无统计学意义(P>0.05)。IMRT-FFF模式下心脏、左前降支、健侧乳腺、肝脏的D_(mean)以及患侧肺的V5均低于IMRT-FF模式(P<0.05),皮下0~2 mm、2~5 mm区域的D_(50)、D_(95)、D_(mean)以及5~8 mm区域的D_(50)、D_(mean)均有统计学意义(P<0.05)。IMRT-FFF模式的MU较IMRT-FF模式明显增加(P<0.001),但治疗时间(实际出束时间)显著低于IMRT-FF模式(P<0.001)。结论IMRT-FFF和IMRT-FF两组计划靶区结果相似,IMRT-FFF模式下皮肤受照剂量明显较低,且在保护危及器官、提高治疗效率方面优势更明显。Objective To compare the dosimetry difference and the skin radiation dose between 6 MV X-ray flattening filter free(FFF)mode and flattening filter(FF)mode in intensity modulated radiotherapy(IMRT)after breast conserving surgery.Methods A total of 42 breast cancer patients with postoperative radiotherapy were selected and the IMRT-FFF plan and IMRT-FF plan were designed respectively.When clinical requirements were met,the dosimetric parameters,monitor units(MU)and total beam-on time were compared between the two groups of target and region of interest.Results In the left breast cancer plans,V_(95%)and conformity index in IMRT-FFF mode were better than those in IMRT-FF mode(P<0.05);in the right breast cancer plans,IMRT-FFF mode V_(95%)was better than IMRT-FF mode(P<0.05),and other target parameters had no statistical significance(P>0.05).In IMRT-FFF mode,D_(mean) of heart,left anterior descending,healthy breast,liver,as well as V5 of affected lung were lower than those in IMRT-FF mode(P<0.05),D_(50),D_(95),D_(mean) in subcutaneous 0-2 mm and 2-5 mm area and D_(50),D_(mean) in 5-8 mm area were statistically significant(P<0.05).The MU of IMRT-FFF mode was significantly increased compared with that of IMRT-FF mode(P<0.001),but the treatment time(the beam-on time)was significantly lower than that in IMRT-FF mode(P<0.001).Conclusion The target area results of IMRT-IFF plan and IMRT-FF plan were similar.In the IMRT-FFF mode,the dose of skin exposure is significantly lower,and it has more obvious advantages in protecting organs at risk and improving treatment efficiency.

关 键 词：乳腺癌 调强放疗 非均整模式 均整模式 剂量学比较 

分 类 号：R737.9[医药卫生—肿瘤]