基于MR超长期延迟强化量化分析鼻咽癌放疗GTV退缩规律的研究  

Quantitative analysis of GTV regression in radiotherapy of nasopharyngeal carcinoma based on enhanced ultra-long-term-delayed enhanced MR scan

作　　者：苏亚 王俪臻 巩贯忠 卢洁 谷玉萍 尹勇 Ya Su;Lizhen Wang;Guanzhong Gong;Jie Lu;Yuping Gu;Yong Yin(Department of Radiation Physics,Shandong First Medical University Affiliated Cancer Hospital,Shandong Cancer Hospital and Institute(Shandong Cancer Hospital),Jinan 250117,China)

机构地区：[1]山东第一医科大学附属肿瘤医院放射物理技术科,山东省肿瘤防治研究院(山东省肿瘤医院),济南市250117

出　　处：《中国肿瘤临床》2021年第22期1158-1163,共6页Chinese Journal of Clinical Oncology

基　　金：山东省自然科学基金面上项目(编号:ZR2020MH227);广西重点研发计划(编号:AB17195005)资助。

摘　　要：目的:探讨基于MR超长期延迟强化扫描对鼻咽癌(nasopharyngeal carcinoma,NPC)肿瘤靶区及淋巴结不同区域差异性退缩规律的研究。方法:选取2019年12月至2020年8月山东省肿瘤医院53例接受放疗的NPC患者,获得放疗前、中及后MR(T2WI、15s强化及>10 min超长期延迟强化的T1WI像)。在T2WI上确定大体肿瘤靶区(GTVp)和淋巴结(GTVn)。根据15 s强化与>10 min强化T1WI的剪影图像确定造影剂清除比较快的区域(GTVp_(快)、GTVn_(快)),清除慢的区域(GTVp_(慢)、GTVn_(慢)),分析不同亚靶区放疗后的退缩差异性。结果:1)GTVp在接受50 Gy及放疗结束的退缩率分别为57.37%、18.61%,低于GTVp_(快)的64.52%、29.66%,而显著高于GTVp_(慢)的25.21%、7.55%(P<0.05),GTVn、GTVn_(快)、GTVn_(慢)的退缩也具有相似变化趋势;2)放疗前、后GTVp_(快)与GTVp、GTVn_(快)与GTVn体积变化均具有相关性(r=0.872、0.998,P<0.05)。而GTVp_(慢)与GTVp、GTVn_(慢)与GTVn体积变化差异无统计学意义(P<0.05);3)放疗后GTVp_(慢)与接受50 Gy放疗时相比体积增加了7.55%,而GTVp与GTVp_(快)、GTVp_(慢)的退缩均小于淋巴结。结论:MR超长期延迟强化扫描可以将NPC及阳性淋巴结分为造影剂清除快、慢的亚区域,不同亚区域及整体靶区退缩显著不同步;在以体积为标准进行NPC放疗疗效评估时,不同亚区域应行个体化分析。Objective:To assess the differential withdrawal rules of tumor target and lymph nodes in nasopharyngeal carcinoma(NPC)based on ultra-long-term-delayed enhanced MR scanning.Methods:Fifty-three patients with NPC who received radiotherapy at Shandong Cancer Hospital from December 2019 to August 2020 were prospectively observed.MR simulation positioning images,including T2-weighted images(T2 WIs),15-s enhanced T1-weighted images(T1 WIs),and 10-min enhanced T1 WIs,were obtained before,during,and after radiotherapy.Gross tumor target(GTVp)and positive lymph nodes(GTVn)were delineated on T2 WIs.Based on silhouette images of 15-s enhanced T1 WI and>10-min enhanced T1 WI,areas with fast contrast medium clearance(GTVp fast and GTVn fast)and slow contrast medium clearance(GTVp slow and GTVn slow)were determined,and the effects of withdrawal after radiotherapy in different sub-target areas were analyzed.Results:1)The withdrawal rates of GTVp after receiving 50 Gy radiotherapy and at the end of radiotherapy were57.37%and 18.61%,respectively,which were lower than 64.52%and 29.66%,respectively,for GTVp fast and significantly higher than25.21%and 7.55%,respectively,for GTVp low(P<0.05).The withdrawal rates of GTVn,GTVn fast,and GTVn slow also had a similar trend.2)Before and after radiotherapy,GTVp fast and GTVp and GTVn fast and GTVn volumes were correlated(r=0.872,0.998;P<0.05).There was no correlation between GTVp slow and GTVp and GTVn slow and GTVn volume change(P<0.05).3)The GTVp slow volume after radiotherapy increased by 7.55%compared with that after 50 Gy radiotherapy,while the with drawal of GTV,GTVp fast,and GTVp slow was lower than that of lymph nodes.Conclusions:NPC and positive lymph nodes can be divided into sub-regions with fast and slow clearance of contrast media based on ultra-long-term delayed enhanced MR scanning.The withdrawal of different sub-regions and overall target region is significantly asynchronous.When the efficacy of radiotherapy for NPC is evaluated based on volume,different sub-regions should be

关 键 词：鼻咽肿瘤 磁共振成像 磁共振剪影 亚靶区勾画 大体肿瘤体积 

分 类 号：R739.63[医药卫生—肿瘤]