胸部食管癌放射治疗心脏及心包受量量化分析  

Quantification of the dose for heart and pericardium in thoracic esophageal cancer radiotherapy

作　　者：佟颖 程品晶[2] 卢洁[1] 陈进琥 刘同海 巩贯忠 TONG Ying;CHENG Pin-j ing;LU Jie;CHEN Jin-hu;L IU Tong-hai;GONG Guan-zhong(Department of Radiation Physics, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences , J inan 250117 , P. R. China;School of Nuclear Science and Technology ,University of South China, Hengyang 421001, P. R. China)

机构地区：[1]山东大学附属山东省肿瘤医院放射物理技术科山东省医学科学院,山东济南250117 [2]南华大学核科学技术学院,湖南衡阳421001

出　　处：《中华肿瘤防治杂志》2018年第5期340-343,348,共5页Chinese Journal of Cancer Prevention and Treatment

基　　金：国家自然科学基金(81301936)

摘　　要：目的心跳运动会导致心脏结构实际剂量和计划剂量之间存在差异,但目前对于心跳导致的心脏结构受量评估误差范围的研究较少。本研究基于屏气下心电门控四维螺旋断层扫描(four-dimensional computed tomography,4DCT)分析心跳对食管癌放疗中心脏及心包剂量-体积指标的影响。方法对山东大学附属山东省肿瘤医院2015-03-26-2016-11-24的22例胸段食管癌患者的心电门控4DCT图像进行回顾性分析,将4DCT图像传入商用软件MIM Maestro(MIM)进行心脏及心包的勾画。在所有患者的定位CT上进行计划设计,剂量分布导入MIM进行四维剂量体积直方图(four-dimensional dose-volume histogram,4D-DVH)重建。分析心跳周期中心脏及心包的体积及相似性指数(dice similarity coefficient,DSC)变化,及由这些变化所引起的Dmean、V20、V30及V40等剂量-体积指标变化。结果心脏的体积及DSC变化均大于心包,且心脏和心包的不同时相体积及DSC之间差异均有统计学意义,均P<0.05。心脏及心包Dmean变化率分别为(3.33±1.04)%和(2.66±1.15)%,V20、V30及V40最大差值分别为(1.94±0.77)%、(1.34±0.66)%、(1.97±0.78)%和(1.34±0.71)%、(1.39±0.42)%和(0.91±0.23)%,且差异均无统计学意义,均P>0.05。心跳导致心包轮廓不能包含所有时相心脏,心脏轮廓超出心包的体积最大为13.77%,由此引起的Dmean差值最高达2.08Gy。而由心跳造成的各个时相心包Dmean超出心脏Dmean的值最大可达1.80Gy。结论胸部食管癌放疗时,心跳可能不是影响心脏及心包剂量-体积指标准确评估的主要因素。对于可能伴有心脏功能不全的患者,有必要进行心脏和心包的双重剂量限制。OBJECTIVE The cardiac movement can lead to the difference between the planning dose and the actual dose,there were few studies analyzing the dosimetric variation range in the cardiac structures caused by cardiac movement.The purpose of this study was to analyze the impact of cardiac movement on dose-volume parameters for heart and pericardium in esophageal cancer radiotherapy by electrocardiography（ECG）gate four-dimensional computed tomography（4 DCT）based on breath-hold.METHODS Totally 22 patients＇ 4 DCT images were analyzed retrospectively in this study,which were from Shandong Cancer Hospital between March 26,2015 and November 24,2016,4 DCT images were imported in the commercial software MIM Maestro（MIM）to contour the heart and pericardium.The radiotherapy plan was designed on planning CT images,then the dose distributions of radiotherapy plan were imported in MIM and 4 Ddose-volume histogram was rebuilt.The variation in volume and dice similarity coefficient（DSC）for heart and pericardium were analyzed.The variation in dose-volume parameters such as Dmean,V20,V30 and V40 were analyzed.RESULTS The variation in volume and DSC for the heart were larger than those for the pericardium,and the difference had statistical significance（P〈0.05）.The variation in Dmeanfor heart and pericardium were（3.33±1.04）% and（2.66±1.15）%,respectively.The maximum difference in V20,V30 and V40 for heart and pericardium were（1.94±0.77）% and（1.34±0.66）%,（1.97±0.78）% and（1.34±0.71）%,（1.39±0.42）% and（0.91±0.23）%,respectively,the difference had no statistical significance（P〉0.05）.The dynamic heart could not be included in static pericardium contour because of the cardiac movement,and the largest volume of the dynamic heart beyond the static pericardium contour was 13.77%,which lead to dose variation,the largest difference in Dmeanwas 2.08 Gy.The largest difference between different phases pericardium Dmeanand heart Dmean was 1.80 Gy.CONCLUSIONS Cardiac activity is not a ma

关 键 词：心脏 心包 食管癌 剂量-体积指标 变化 

分 类 号：R735.1[医药卫生—肿瘤]