有无均整器模式下乳腺癌保乳术后瘤床同步推量VMAT剂量学研究  

Dosimetric Study of SIB-VMAT in Tumor Bed After Breast-Conserving Surgery With or Without Flattening Filter Mode

作　　者：程冬 朱斌 刘文敏 付振明 CHENG Dong;ZHU Bin;LIU Wenmin;FU Zhenming(Department of Oncology II,Renmin Hospital of Wuhan University,Wuhan Hubei 430060,China)

机构地区：[1]武汉大学人民医院肿瘤Ⅱ科,湖北武汉430060

出　　处：《中国医疗设备》2023年第7期61-66,共6页China Medical Devices

基　　金：国家自然科学基金面上项目(81773555)。

摘　　要：目的 探讨有无均整器模式下不同部位乳腺癌保乳术后瘤床同步推量容积旋转调强放疗(Simultaneous Integrated Boost of Volumetric Modulated Arc Therapy,SIB-VMAT)的剂量学差异。方法 回顾性分析2022年1—5月于武汉大学人民医院接受保乳术后放疗的早期乳腺癌患者42例,其中左侧保乳术后22例、右侧保乳术后20例,分别对每例患者在相同约束条件下设计有均整器(Flattening Filter,FF)与无均整器(Flattening Filter Free,FFF)模式下两组保乳术后SIB-VMAT计划,靶区处方剂量50 Gy/25次,局部SIB至60 Gy/25次,比较两组计划的剂量学参数、机器跳数(Monitor Unit,MU)和出束时间。结果 FFF模式与FF模式相比,在靶区剂量上,左侧保乳术后PTV-tb的HI、右侧保乳术后PTV-tb的D98%和Dmean以及PTV的D2%和Dmean差异均具有统计学意义(P<0.05);其他靶区参数无统计学差异。左侧保乳术后FFF模式健侧肺、脊髓和对侧乳腺的Dmean均优于FF模式;右侧保乳术后FFF模式健侧肺的Dmean、脊髓的D_(max)优于FF模式,差异均有统计学意义(P<0.05)。两组计划的其他危及器官参数比较,差异均无统计学意义(P>0.05)。FFF模式与FF模式相比,左侧和右侧保乳术后MU均显著增加,但出束时间均显著降低(P<0.05)。结论 所有计划均可满足临床需求,FFF模式较FF模式在保护正常组织和治疗效率上优势更明显,且在FFF模式下,左侧保乳术后SIB-VMAT较右侧保乳术后SIB-VMAT保护正常组织的优势更明显。Objective To investigate the dosimetric comparison of simultaneous integrated boost of volumetric modulated arc therapy(SIB-VMAT)on the tumor bed after breast-conserving surgery for breast cancer at different sites with and without flattening filter mode.Methods A total of 42 patients with breast cancer treated in the Department of Radiotherapy of Renmin Hospital of Wuhan University from January to May 2022 were randomly selected for post breast-conserving lumpectomy simultaneous volume push radiotherapy,including 22 patients after left breast surgery and 20 patients after right breast surgery.SIB-VMAT was designed for both groups under the same constraints with flattening filter(FF)and flattening filter free(FFF)mode.The prescription dose of the target area was 50 Gy/25 times,and the local SIB was up to 60 Gy/25 times.The dosimetry parameters,monitor unit(MU)and beam exit time of the two groups were compared.Results FFF mode compared with FF mode,the differences in target area dose were statistically significant(P<0.05)for HI of PTV-tb after left breast-conserving surgery,D98%and Dmean of PTV-tb after right breast-conserving surgery,and D2%and Dmean of PTV;other target area parameters were not statistically different.The Dmean of the healthy lung,spinal cord,and contralateral breast in the FFF mode were better than in the FF mode after left breast-conserving surgery;the Dmean of the healthy lung and D_(max) of the spinal cord in the FFF mode were better than in the FF mode after right breastconserving surgery,and the differences were statistically significant(P<0.05).There was no statistically significant difference between the two groups of planned parameters for other organs at risk(P>0.05).Compared with the FF mode,the left and right breast-conserving surgeries in the FFF mode showed a significant increase in MU,but the beam exit time was significantly reduced(P<0.05).Conclusion All plans can meet the clinical needs,and the FFF mode is better than the FF mode in protecting normal tissues and has higher treatm

关 键 词：乳腺癌 保乳术 容积旋转调强放疗 均整器 剂量学 

分 类 号：R144[医药卫生—公共卫生与预防医学] R730.55