基于PET-CT的SUV值与基于4DCT的EE时相勾画胸段食管癌GTV相关性分析  

Analysis of correlation between GTVs delineated based on SUVs of PET-CT and EE phase of 4DCT in thoracic esophageal cancer

作　　者：郭延娈 李建彬[2] 李奉祥[2] 丁昀[1,4] 刘姗姗[2] 段益利 尚东平[2] 付政[3] 

机构地区：[1]山东省肿瘤医院和研究所放疗科,济南250117 [2]山东省肿瘤医院和研究所大孔径CT室, 济南250117 [3]山东省肿瘤医院和研究所PET-CT室, 济南250117 [4]济南大学 山东省医学科学院 医学与生命科学学院

出　　处：《中华放射肿瘤学杂志》2015年第2期121-125,共5页Chinese Journal of Radiation Oncology

摘　　要：目的 探讨基于PET-CT图像SUV阈值≥2.O及20％ SUVmax与基于4DCT的EE时相图像勾画胸段食管癌原发肿瘤GTV相关性因素.方法 22例胸段食管癌患者序贯完成3DCT、4DCT、FDG PET-CT胸部定位扫描.基于4DCT的EE时相图像勾画GTV50％.基于SUV≥2.0、20％SUVmax分别在PET图像上勾画IGTVPET并分别命名为IGTVPET2.0、IGTVPET20％.获得GTV50％最大横径、GTV50％大小、上下方向位移、三维运动矢量和SUVmax.结果 IGTVPET2.0、IGTVPE20％与GTV50％间体积比与GTV50％最大横径、GTV50％大小、上下方向位移、三维运动矢量均无相关性（P=0.055 ～0.932）;IGTVPET2.0、IGTVPET20％与GTV50％间CI与GTV50％最大横径、GTV50％大小、上下方向位移、三维运动矢量均有相关性（P=0.005～0.033）;IGTVPET20％与GTV50％间体积比、CI与SUVmax均有相关性（P =0.001、0.016）.结论 基于PET-CT图像构建的IGTV并不能客观真实反映肿瘤空间位置变化及运动信息,而且单一数值的SUV阈值选取也是不可靠的.构建食管癌原发肿瘤靶区时应依据4DCT所构建IGTV纠正PET-CT所构建IGTV边界及其位置.Objective To investigate the correlation factors in delineating the gross tumor volume （GTV） of primary tumor in thoracic esophageal cancer based on the positron emission tomography-computed tomography （PET-CT） （thresholds of standardized uptake value or SUV ≥2.0 and ≥20% of maximum SUV or SUVmax） and the end-expiration （EE） phase of four-dimensional computed tomography （4DCT）.Methods Twenty-two patients with thoracic esophageal cancer sequentially underwent 3DCT,4DCT,and F-fluorodeoxyglucose PET-CT for thoracic localization.GTV50% was delineated by the EE phase of 4DCT.The internal GTVs based on PET-CT images （IGTVPET） were delineated by two thresholds：SUV ≥2.0 and ≥20% of SUVmax,and designated as IGTVPET2.0 and IGTVPT20%,respectively.The maximum transverse diameter of GTV50%,volume of GTV50%,the displacement in cranial-caudal （CC） direction,3D motion vector,and SUVmax were obtained.Results The maximum transverse diameter of GTV50%,volume of GTV50%,the displacement in CC direction,and 3D motion vector showed no significant correlations with the volume ratio （VR） of IGTVPTV20% or IGTVPET2.0 to GTV50% （P =0.055-0.932）,but showed significant correlations with the conformity index （CI） between IGTVPET20% or IGTVPET2.0 and GTV50% （P =0.005-0.033）.Significant correlations were observed between the VR and CI of IGTVPET20% to GTV50% and SUVmax（P =0.001 and 0.016,respectively）.Conclusions IGTV based on PET-CT images cannot objectively and accurately reflect the changes in spatial position and motion of the tumor,and the selection of a single SUV threshold is unreliable.To determine the primary tumor target in esophageal cancer,the IGTV based on 4DCT should be used to correct the boundary and position of IGTV constructed based on PET-CT.

关 键 词：体层摄影术 正电子发射 氟脱氧葡萄糖 标准摄取值 体层摄影术 X线计算机 四维 内大体肿瘤体积 食管肿瘤/放射疗法 

分 类 号：R735.1[医药卫生—肿瘤] R730.55[医药卫生—临床医学]