不同体位固定方式对乳腺癌放疗摆位精度的影响

目的:探讨使用4种不同体位固定方式用于乳腺癌放疗定位,并对4种不同的固定方式的摆位精度分析和比较,为临床应用提供参考.方法:选取2018年11月至2019年1月我院收治的乳腺癌放疗患者34例,其中乳腺癌保乳术后患者20例,乳腺癌根治术后(锁骨上下区放疗)患者14例.将乳腺癌保乳术后患者20例分为A、B两组,分别采用负压...

Effects of different fixation methods on positioning error of breast cancer radiotherapy

Objective:To investigate the application of four different fixation methods for breast cancer radiotherapy positioning,and analyze the positioning accuracy,so as to provide reference for clinical application.Methods:From November 2018 to January 2019,a total of 34 cases of breast cancer radiotherapy patients were selected,which included 20 cases had breast conserving surgery and 14 cases of breast cancer patients after radical surgery(radiotherapy in the supraclavicular region).20 cases of breast cancer patients after breast conserved surgery were divided into group A and group B,A used vacuum pad and head thermoplastic mask fixation,B used breast bracket.14 cases of breast cancer patients after radical surgery were divided into group C and group D,respectively used neck and shoulder thermoplastic mask(C hands side,D hands grasping ears).We can use Philips Bigbore CT to perform positioning scanning,and transfer images to the Varian Ecplipse treatment planning system for reconstruction and plan design.After the first treatment,patients must complete CT scan,so we can register verified image with the planned image,measure the coordinate error of the treatment center,and then use SPSS18.0 statistical software for statistical analysis of the data,then get the positioning error.Results:The positioning errors of group A in the X,Y and Z directions were(1.7±1.9)mm,(2.1±2.9)mm and(2.0±1.2)mm,respectively.The positioning errors of group B in the X,Y and Z directions were(2.8±1.1)mm,(3.7±1.1)mm and(4.8±1.3)mm,respectively.The positioning errors of group C in the X,Y and Z directions were(2.1±1.6)mm,(2.1±1.5)mm and(3.6±3.1)mm,respectively.The positioning errors of group D in X,Y and Z directions were(1.0±0.5)mm,(1.9±1.5)mm and(3.6±1.9)mm,respectively.The positioning error of group A in the Y and Z directions was smaller than that of group B(P=0.048,0.038),and there was no significant difference in the positioning error of group A and group B in the X direction( P >0.05).There was no significant difference in the positioning error between C group and D group in the X,Y and Z directions( P >0.05). Conclusion: Radiotherapy for breast cancer conserving surgery,the vacuum pad and head thermoplastic mask fixation can reduce the positioning error compared with the breast bracket.For breast cancer patients after radical surgery,there is no significant difference in positioning error between the two fixation techniques by neck and shoulder mold,so it is recommended to use the ear grasping method to reduce the dose error caused by the connection between adjacent fields.