不同射野方法在宫颈癌术后放射治疗中的剂量学比较  

Dosimetry comparison of different radiation field methods in cervical cancer radiotherapy

作　　者：葛彬彬[1] 储开岳[1] 金建华[1] 赵永亮[1] 曹顾飞 刘于[1] 杨晓梅[1] GE Bin-bin;CHU Kai-yue;JIN Jian-hua;ZHAO Yong-liang;CAO Gu-fei;LIU Yu;YANG Xiao-mei(Nantong Tumor Hospital,Cancer Hospital Affiliated to Nantong University,Nantong 226361,Jiangsu,China)

机构地区：[1]南通市肿瘤医院·南通大学附属肿瘤医院,江苏南通226361

出　　处：《生物医学工程与临床》2021年第2期179-183,共5页Biomedical Engineering and Clinical Medicine

基　　金：江苏省重点研发计划项目(BE2017679);南通市指导性计划项目(GJZ17043)。

摘　　要：目的分析比较3种不同射野方法在宫颈癌术后放射治疗中的剂量学情况。方法选择30例宫颈癌术后放射治疗患者,年龄37~68岁,中位年龄54岁。对所有病例进行3种不同射野方法计划设计,分别为5野调强放射治疗(5FIMRT)、7野调强放射治疗(7FIMRT)、单弧容积旋转调强放射治疗(VMAT),处方剂量均设计为45 Gy/25 F。对比3组治疗计划的靶区剂量、适形度指数(CI)、均匀性指数(HI),以及危及器官的受照剂量、机器跳数和治疗时间等。结果靶区CI:VMAT优于7FIMRT(0.879±0.027 vs 0.859±0.032;t=5.759,P<0.05),而7FIMRT优于5FIMRT(0.859±0.032vs 0.835±0.033;t=4.739,P<0.05);靶区HI:VMAT与7FIMRT相当(0.119±0.019 vs 0.119±0.016;t=0.045,P=0.954),却优于5FIMRT(0.119±0.019 vs 0.123±0.017;t=6.587,P<0.05);但VMAT靶区内平均剂量[(47.73±0.56)Gy]略高于5FIMRT[(47.55±0.47)Gy]、7FIMRT[(47.51±0.43)Gy](t=6.753、8.613,P<0.05);在危及器官的保护上,VMAT计划的直肠和膀胱受照剂量尤其在高剂量区域(V_(30)、V_(40))比IMRT有所减少,股骨头受照剂量整体(V_(20)、V_(30)、V_(40))都有下降,脊髓最大剂量(D2%)明显下降,其他参数差异无统计学意义(P>0.05)。VMAT相比于5FIMRT、7FIMRT治疗时间缩短一半以上[VMAT:(3.38±0.20)min;5FIMRT:(6.22±0.31)min;7FIMRT:(8.11±0.23)min。t=7.231、9.478,P<0.05],机器跳数也有减少(VMAT:574±75;5FIMRT:606±74;7FIMRT:666±88。t=2.783、3.424,P<0.05)。结论需要接受放射治疗的宫颈癌患者,IMRT与VMAT两种技术均可达到靶区剂量要求。在机器条件及经济条件允许的前提下,推荐使用VMAT;它在治疗时间、治疗精度和危及器官的保护等方面优于IMRT,具有一定的临床优势。Objective To analyze and compare three dosimetry field methods in postoperative radiotherapy for cervical cancer.Methods A total of 30 postoperative radiotherapy patients with cervical cancer were enrolled,which aged 37-68 years old with median age of 54 years old.Three different radiation field methods were performed,including five-field intensity modulated radiation therapy(5 FIMRT),seven-field intensity modulated radiation therapy(7 FIMRT)and volumetric modulated arc therapy(VMAT),and prescription dose was all designed 45 Gy/25 F.The dose,conformity index(CI),homogeneity index(HI)of planning target volume(PTV),exposure dose of organ at risk(OAR),number of monitor unit(MU)and treatment time were compared in 3 groups.Results The CI of PTV:VMAT was better than that of 7 FIMRT(0.879±0.027 vs 0.859±0.032.t=5.759,P<0.05),and 7 FIMRT was better than that of 5 FIMRT(0.859±0.032 vs 0.835±0.033.t=4.739,P<0.05);The HI of PTV:VMAT was similar to that of 7 FIMRT(0.119±0.019 vs 0.119±0.016.t=0.045,P=0.954),and better than that of 5 FIMRT(0.119±0.019 vs 0.123±0.017.t=6.587,P<0.05);Mean dose of PTV:VMAT[(47.73±0.56)Gy]was slightly higher than that of 5 FIMRT[(47.55±0.47)Gy]and 7 FIMRT[(47.51±0.43)Gy](t=6.753,8.613,P<0.05);OAR protection:for exposure of rectum and bladder,VMAT was significantly lower than that of IMRT,especially in high-dose areas(V_(30),V_(40)),the femoral head decreased overall(V_(20),V_(30),V_(40)),and maximum dose(D2%)of spinal cord were significantly decreased.There was no significant difference in other parameters(P>0.05).Compared with IMRT,VMAT significantly shortened treatment time by more than half[VMAT:(3.38±0.20)minutes;5 FIMRT:(6.22±0.31)minutes;7 FIMRT:(8.11±0.23)minutes;t=7.231,9.478,P<0.05],and numbers of MU also significantly decreased(VMAT:574±75;5 FIMRT:606±74;7 FIMRT:666±88;t=2.783,3.424,P<0.05).Conclusion It is demonstrated that IMRT and VMAT could meet the target dose requirements of cervical cancer patients in radiotherapy.It is recommended to use VMAT in machine and econ

关 键 词：宫颈癌 调强放射治疗 容积旋转调强放射治疗 治疗剂量 治疗精度 治疗时间 剂量学 危及器官 

分 类 号：R737.33[医药卫生—肿瘤] R730.55[医药卫生—临床医学]