摘要
目的研究乳腺癌保乳术后患者应用固定野调强放疗（FF-IMRT）和螺旋断层治疗（HT）计划的剂量学差异。方法选择10例左侧乳腺癌保乳术后IMRT患者，CT模拟定位、勾画靶区及危及器官，对同-CT图像设计FF—IMRT计划和HT计划。配对t检验两种计划靶区及危及器官剂量分布及照射时间差异。结果与FF—IMRT计划相比，HT计划的100％PTV覆盖度增加（P110．000），105％PTV覆盖度降低（P110．000），平均剂量（Dmean）降低（P=0．002），均匀指数（HI）、适形指数（CI）增加（P=0．001、0．023）。HT计划的患侧肺剂量体积V5、V10、V20、V30、V40、Dmean。分别降低28％、30％、35％、46％、61％、32％（P=0．000），双肺的分另0降低30％、28％、34％、46％、62％、26％（P=0．000），心脏的和最大剂量（Dmax）分别降低57％、59％、71％、82％、91％、45％和12％（P=0．000～0．002），健侧乳腺Dmean、Dmax分别增加0．9、3．0Gy（P=0．000、0．000），健侧肺的分别增加0．42、2．70Gy（P=0．000、0．000）。HT计划照射时间明显高于FF—IMRT计划（11．98min：5．96min，P=0．000）。结论左侧如乳腺癌HT计划的靶区均匀性和适形度均优于FF—IMRT计划，危及器官可获得等同于或优于FF—IMRT计划的剂量分布，可作为新照射方式用于乳腺癌保乳术后患者。
Objective To compare the dosimetry difference between helical tomotherapy and fixed field IMRT for breast cancer radiotherapy after breast-conserving surgery. Methods Ten patients received radiotherapy after breast-conserving surgery were selected. For each patient, two treatment plans （FF-IMRT plan and HT plan） were designed with Eclipse and TomoTberapy. Same institutional dose-volume constraints for breast cancer were used in both techniques. Targets and organs at risk were compared with paired t-test for two planning. Results In comparison with the FF-IMRT planning, PTV coverage of HT plan group increased, Dine became lower （P =0. 000,0. 002）. the HI and CI were significantly higher for HT （P = 0. 001,0. 023 ）. Compared with the FF-IMRT plans, V5 , Vi0, V20, V30, V40 and D of the ipsilateral lung were reduced by about 28% ,30% ,35% ,46% ,61% and 32% （ P = 0. 000） , those of full lung were reduced by about 30% ,28% ,34% ,46% ,62% and 26% （P=0.000） , those and Dmax of heart were reduced by about 57%,59%,71%,82%,91%,45% and 12% （P= 0.000=43.002）. The D and Dmax of contralateral breast were higher by 0. 9 Gy and 3.0 Gy （ P = 0. 000, 0. 000 ） respectively, those of contralateral lung were higher by 0. 42 Gy and 2. 70 Gy （ P = 0. 000, 0. 000 ） respectively. It takes significantly long time for the HT plans designed than FF-IMRT plan （ 11.98 rain ： 5.96 min, P = 0. 000 ）. Conclusions The HT planning improve the HI and CI of PTV, organs at risk can get equivalent or superior dose distribution compared with the FF-IMRT technology, but it is feasible for clinical applications in breast- conserving surgery as a new method.
出处
《中华放射肿瘤学杂志》
CSCD
北大核心
2013年第5期411-414,共4页
Chinese Journal of Radiation Oncology
关键词
乳腺肿瘤
固定野调强放射疗法
乳腺肿瘤
螺旋断层疗法
剂量学
Breast neoplasms/fixed field intensity-modulated radiotherapy
Breast neoplasms/ helical tomotherapy
Dosimetry
