补偿膜与皮肤间空腔对乳腺癌改良根治术后放疗剂量的影响  

Effect of the Cavity of Bolus and Skin on Radiotherapy Dose after Modified Radical Mastectomy

作　　者：唐静宜 李金凯 王沛沛 李彩虹 昌志刚 顾宵寰 胡晓伟 李华玲 孙新臣 TANG Jingyi;LI Jinkai;WANG Peipei;LI Caihong;CHANG Zhigang;GU Xiaohuan;HU Xiaowei;LI Hualing;SUN Xinchen(School of First Clinical Medical,Nanjing Medical University,Nanjing Jiangsu 210000,China;Department of Radiotherapy,Jiangsu Province Hospital/The First Affiliated Hospital with Nanjing Medical University,Nanjing Jiangsu 210029,China)

机构地区：[1]南京医科大学第一临床医学院,江苏南京210000 [2]江苏省人民医院/南京医科大学第一附属医院放疗科,江苏南京210029

出　　处：《中国医疗设备》2023年第8期16-20,共5页China Medical Devices

基　　金：国家自然科学基金面上项目(82073344;81874217;81672983)。

摘　　要：目的 研究乳腺癌根治术后放疗中补偿膜与人体空腔间隙大小对靶区及危及器官的剂量学影响。方法 选取20例左侧乳腺癌根治术患者的CT定位图像,将皮肤轮廓分别外扩2、5、10 mm,将外扩部分CT值设置为0,从而模拟补偿膜与人体表面的空腔间隙。基于靶侧胸壁增加1 cm虚拟补偿膜,根据空腔间隙大小制定4种容积旋转调强放疗计划方案:无空腔组、2 mm空腔组、5 mm空腔组、10 mm空腔组,并将原始计划作为对照组,评价不同组间靶区和浅表皮肤、心脏、患侧肺、患侧肱骨头的剂量差异。结果 5组计划所有靶区剂量学指标均满足处方剂量要求,无空腔组、2 mm空腔组、5 mm空腔组与对照组的计划靶区剂量(Planning Target Volume,PTV50)比较,差异均有统计学意义(P<0.05),且随着空腔的增大,PTV50呈降低的趋势;无空腔组、2 mm空腔组、5 mm空腔组、10 mm空腔组与对照组的适形度指数比较,差异均有统计学意义(P<0.05);无空腔组、2 mm空腔组、5 mm空腔组、10 mm空腔组与对照组的均匀性指数比较,差异均无统计学意义(P>0.05)。针对浅表皮肤,2 mm空腔组、5 mm空腔组、10 mm空腔组与对照组的Dmin、Dmax、Dmean剂量比较,差异均有统计学意义(P<0.05),且随着空腔的增大,浅表皮肤Dmean剂量呈增加的趋势。空腔对于患侧肺、肱骨头、心脏的受量影响较小,差异均无统计学意义(P>0.05)。结论 空腔间隙会对靶区及浅表皮肤剂量产生影响,放疗摆位时应尽可能减少空腔间隙的产生。Objective To study the dosimetric effect of the cavity of the bolus and skin on the target area and organs at risk during radiotherapy after modified radical mastectomy.Methods CT localization images of 20 patients with left side radical mastectomy were selected.The skin contour was expanded outward by 2,5 and 10 mm,respectively,and the CT value of the enlarged part was set as 0 to simulate the cavity gap between the bolus and skin.Based on the addition of 1 cm virtual compensation film on the chest wall of the target side,four kinds of volume rotation intensity modulation plans were developed according to the space size:no cavity group,2 mm cavity group,5 mm cavity group,10 mm cavity group and the original group was selected as the control group to evaluate dose differences among different groups in the target area and superficial skin,heart,affected lung and affected humeral head.Results All the target dosimetric indexes of the five groups met the prescription dose requirements,there was statistically significant difference of the planning target volume(PTV50)between the no cavity group,2 mm cavity group,5 mm cavity group and the control group(P<0.05).In addition,with the increase of the cavity,PTV50 decreased.There was statistically significant difference of the conformity index between the no cavity group,2 mm cavity group,5 mm cavity group,10 mm cavity group and the control group(P<0.05).There was no statistically significant difference of the heterogeneity index between the no cavity group,2 mm cavity group,5 mm cavity group,10 mm cavity group and the control group(P>0.05).For superficial skin,there was statistically significant difference in Dmin,Dmax and Dmean doses between the 2 mm cavity group,5 mm cavity group,10 mm cavity group and the control group(P<0.05),and the Dmean dose of superficial skin showed an increasing trend with the increase of cavity.The influence of cavity on the affected lung,humeral head and heart was relatively small,and the difference was not statistically significant(P>0.05).Conc

关 键 词：补偿膜 空腔间隙 乳腺癌 靶区 危及器官 

分 类 号：R144[医药卫生—公共卫生与预防医学] R737.33