多叶准直器角度改变对左侧全乳大分割放疗瘤床推量的剂量学影响  

Dosimetric effect of multi-leaf collimator angle change on the left-sided breast hypofractionated radiotherapy with simultaneous integrated boost

作　　者：陈车 陈睿 陆治江 罗德红 CHEN Che;CHEN Rui;LU Zhijiang;LUO Dehong(Cancer Clinical Medical Center,Radiation Oncology Center,the First People Hospital of Zunyi/the Third Affiliated Hospital of Zunyi Medical University,Zunyi 563099,China)

机构地区：[1]遵义市肿瘤临床医学中心、遵义市第一人民医院(遵义医科大学第三附属医院)放疗中心,遵义563099

出　　处：《辐射研究与辐射工艺学报》2023年第4期51-57,共7页Journal of Radiation Research and Radiation Processing

基　　金：遵义市科技计划项目(HZ(2020)103号)资助。

摘　　要：研究动态调强放疗方式下多叶准直器角度改变对左侧全乳大分割放疗内侧、中间和外侧瘤床同期推量的剂量学影响。选取2018年01月至2023年01月间于遵义第一人民医院收治的左侧乳腺癌保乳术后行全乳大分割放疗瘤床同期推量患者60例,按瘤床位置分为内侧、中间和外侧3组,分别对比各组患者多叶准直器角度改变的放疗计划(标记为Plan-A)与多叶准直器角度为0°的原放疗计划(标记为Plan-O)的靶区、心肺剂量学参数差异。结果显示:3组患者的Plan-A较Plan-O,靶区处方覆盖(V(处方(%)))、适形度指数(Conformity Index,CI)和均匀性指数(Homogeneity Index,HI)均无显著差异;在内侧组采用Plan-A相较于Plan-O,左肺(V_(5)、V_(10)和D_(mean))、心脏(V_(8)和D_(mean))和冠状动脉左前降支(LAD)(D_(max)和D_(mean))均降低,差异有统计学意义(p<0.05);同时Plan-A较Plan-O,在中间和外侧组中仅外侧组LAD(D_(max)和D_(mean))明显减小(p<0.05),其余心肺受量参数均无显著差异。准直器角度改变对左侧全乳大分割放疗瘤床推量靶区剂量学参数无明显影响,但能使内侧组患者的心肺受量较原放疗计划明显减小,故对于左侧大分割单纯全乳放疗内侧瘤床制定放疗计划建议选择改变多叶准直器角度。This study aimed to evaluate the effects of multi-leaf collimator angle change on the dosimetric parameters of the medial,central,and lateral tumor bed boost in hypofractionated left whole-breast irradiation with dynamic multi-leaf collimator technology.Sixty patients with early breast cancer following conservative surgery who underwent hypofractionated radiotherapy with tumor bed boost were enrolled from The First People’s Hospital of Zunyi between January 2018 and January 2023.All patients were classified into three groups according to the location of the tumor bed:medial,central,and lateral.The differences in target volume and cardiopulmonary dosimetric parameters between the plan of multi-leaf collimator angle change(labeled as Plan-A)and the original plan of 0°multi-leaf collimator angle(labeled as Plan-O)were compared in each group.The results did not show any significant differences in the coverage of the target prescription,conformability index,and homogeneity index between Plan-A and Plan-O of the three groups.In the medial group,the left lung V_(5),V_(10),and D_(mean);heart V_(8)and D_(mean);and left anterior descending artery(LAD)D_(max)and D_(mean)of Plan-A were significantly lower than those of Plan-O(p<0.05).Meanwhile,in the central and lateral groups,only the LAD D_(max)and D_(mean)of Plan-A decreased significantly in the lateral group,and no differences were observed in other cardiopulmonary parameters compared to those in Plan-O(p<0.05).In conclusion,the change in collimator angle did not have a significant effect on the target dosimetric parameters of hypofractionated radiotherapy with tumor bed boost for the left breast.On the contrary,it could significantly reduce the cardiopulmonary dose in the medial group compared to the original radiotherapy plan.Given this information,it is recommended to change the multi-leaf collimator angle for the radiotherapy plan of the medial tumor bed group in left whole-breast hypofractionated radiotherapy.

关 键 词：乳腺癌 多叶准直器 大分割放疗 瘤床位置 剂量学 

分 类 号：R815[医药卫生—放射医学] R737.9[医药卫生—临床医学]