乳腺癌保乳术后调强放疗2种体位固定方式的比较

Comparison of Two Body Position Fixation Methods in Intensity-modulated Radiotherapy after Breast Cancer Breast-conserving Surgery

目的:比较乳腺癌保乳术后调强放射治疗时2种体位固定方式的误差值,以选择出较佳的提高摆位精度的固定方法。方法:随机将乳腺癌保乳术后患者分为2组,一组用真空垫固定,另一组用热塑料膜固定,各10例,所有患者分别在调强放疗前用锥形束CT(CBCT)进行摆位验证,比较2组摆位误差值。结果:在头脚、左右、腹背方向误差值,真空垫组分别为(2.5±0.926)、(2.7±0.725)、(2.4±0.839)mm,热塑料膜组分别为(3.9±0.805)、(3.6±0.782)、(2.8±0.772)mm。真空组在头脚、左右方向的误差值比热塑料膜组小,有统计学意义(P<0.5)。结论:乳腺癌保乳术后调强放疗,使用真空垫固定体位更能提高摆位重复性,提高摆位精度,尤其适用于体型偏胖的患者。

Objective To determine the fixation method for enhanced positioning accuracy by comparing two body position fixation methods in the intensity-modulated therapy after the breast cancer breast-conserving surgery, Methods 20 cases undergoing breast cancer breast-conserving surgery were divided into two groups, of which, 10 ones were fixed with the vacuum cushion and the remained 10 ones with the thermoplastic film. The positioning errors of the two groups were compared. Results In the directions of head-foot, left-right and abdomen-back, the errors of the vacuum cushion group were （2.5±0.926） mm, （2.7±0.725） mm and （2.4±0.839） mm respectively, and the ones of the thermoplastics film were （3.9±0.805） mm, （3.6±0.782） mm, （2.8±0.772） mm respectively. The errors of the vacuum group were less than those of the thermoplastic film group, which was statistically significant with P less than 0.5. Conclusion The vacuum cushion can enhance the positioning accuracy and repeatability for the intensity-modulated therapy after the breast cancer breast- conserving surgery, which especially adapts to the overweight ones.