CAJ | 학술논문

目的比较基于三维CT (3DCT)、四维CT (4DCT)和锥形束CT (CBCT)图像勾画所得非小细胞肺癌(NSCLC)靶区位置和体积差异.方法 31例周围型NSCLC患者,序贯完成胸部3DCT和4DCT扫描,基于3DCT制定放疗计划,放疗首次拍摄CBCT,并基于骨性标志配准校正.在3DCT、4DCT的50％时相、最大密度投影(MIP)、CBCT图像上勾画得到GTV3D、GTV4D50％、IGTVMIP和IGVCBCT.对组间位移比较行Wilcoxon秩和检验,靶区位置及包含度比较行配对t检验,肿瘤三维运动相关性行Pearson法分析.结果肺上叶组GTV3D、GTV4D50％、IGTVMIP与IGTVCBCT比值分别为0.77、0.84和1.10(P =0.004、0.005、0.07)；中下叶组比值分别为0.67、0.65和1.17 (P=0.001、0.001、0.020).全组患者GTV4D50％与IGTVCBCT比值与肿瘤三维运动呈负相关(P=0.012).全组患者IGTVCBCT对GTV3D、GTV4D50％、IGTVMIP包含度分别为0.65、0.65和0.62,IGTVCBCT对GTVMIP包含度与IGTVCBCT对GTV3D或GTV4D50％包含度差异无统计学意义(P=0.375、0.167),而GTV3D、GTV4D50％、IGTVMIP对IGTVCBCT包含度分别为0.47、0.49和0.67,IGTVMIP对IGTVCBCT包含度大于GTV3D或GTV4D50％对IGTVCBCT包含度(P=0.000、0.000).结论 CBCT图像包含的肿瘤运动信息量明显大于3DCT图像,但略小于4DCT的MIP图像.即使3DCT、4DCT与CBCT配准校正后也有可能导致较严重的脱靶,这是基于CBCT进行循证靶区和计划修正所需注意的.
목적 비교기우삼유CT (3DCT)、사유CT (4DCT)화추형속CT (CBCT)도상구화소득비소세포폐암(NSCLC)파구위치화체적차이.방법 31례주위형NSCLC환자,서관완성흉부3DCT화4DCT소묘,기우3DCT제정방료계화,방료수차박섭CBCT,병기우골성표지배준교정.재3DCT、4DCT적50％시상、최대밀도투영(MIP)、CBCT도상상구화득도GTV3D、GTV4D50％、IGTVMIP화IGVCBCT.대조간위이비교행Wilcoxon질화검험,파구위치급포함도비교행배대t검험,종류삼유운동상관성행Pearson법분석.결과 폐상협조GTV3D、GTV4D50％、IGTVMIP여IGTVCBCT비치분별위0.77、0.84화1.10(P =0.004、0.005、0.07)；중하협조비치분별위0.67、0.65화1.17 (P=0.001、0.001、0.020).전조환자GTV4D50％여IGTVCBCT비치여종류삼유운동정부상관(P=0.012).전조환자IGTVCBCT대GTV3D、GTV4D50％、IGTVMIP포함도분별위0.65、0.65화0.62,IGTVCBCT대GTVMIP포함도여IGTVCBCT대GTV3D혹GTV4D50％포함도차이무통계학의의(P=0.375、0.167),이GTV3D、GTV4D50％、IGTVMIP대IGTVCBCT포함도분별위0.47、0.49화0.67,IGTVMIP대IGTVCBCT포함도대우GTV3D혹GTV4D50％대IGTVCBCT포함도(P=0.000、0.000).결론 CBCT도상포함적종류운동신식량명현대우3DCT도상,단략소우4DCT적MIP도상.즉사3DCT、4DCT여CBCT배준교정후야유가능도치교엄중적탈파,저시기우CBCT진행순증파구화계화수정소수주의적.
Objective To determine the positional and volumetric differences between the target volumes delineated based on three-dimensional computed tomography (3DCT),four-dimensional computed tomography (4DCT),and cone-beam computed tomography (CBCT) in non-small cell lung cancer (NSCLC).Methods Thirty-one patients with peripheral NSCLC sequentially underwent 3DCT and 4DCT simulation scans of the thorax during normal breathing.A 3D conformal treatment plan was created based on 3DCT.Before the first treatment,CBCT was performed and registered to the planning CT using bony anatomy registration.All contours were delineated by a radiation oncologist using the same contouring protocol.GTV3D and GTV4D50％ were contoured based on 3DCT and end-expiration phase (50％ phase) of 4DCT,respectively;internal GTVs (IGTVMIP and IGTVCBCT) were contoured based on maximum intensity projection (MIP) of 4DCT and CBCT,respectively.The differences in the position,size,and degree of inclusion (DI) between these volumes were determined by Wilcoxon rank-sum test and paired t-test.The Pearson test was used for the correlation analysis on 3D motion vector of GTV.Results The mean size ratio of GTV3D,GTV4D50％,and IGTVMIP to IGTVCBCT were 0.77,0.84,and 1.10(z =-2.91,P =0.004;z =-2.79,P =0.005 ;z =-1.81,P =0.070) for tumors in the upper lobe of the lung and 0.67,0.65,and 1.17(z=-3.30,P=0.001;z=-3.30,P=0.001;z=-2.32,P=0.020)fortumorsinthemiddle/ lower lobe of the lung.GTV4D50％/IGTVCBCT ratio was negatively correlated with the 3 D motion vector of GTV (r =-0.45,P =0.012) in all the patients.The mean DIs of GTV3D,GTV4D50％,and IGTVMIP in IGTVCBCT were 0.65,0.65,and 0.62,respectively,and the DI of GTV3D or GTV4D50％ in IGTVCBCT showed no significant difference from that of IGTVMIP in IGTVCBCT (t =-0.90,P =0.375 ; t =-1.42,P =0.167) ; the mean DIs of IGTVCBCT in GTV3D,GTV4D50％,and IGTVMIP were 0.47,0.49,and 0.67,respectively,and the DI of IGTVCBCT in IGTVMIP was significantly greater than that of IGTVCBCT in GTV3D or GTV4D50％ (t =-8.28,P =0.000 ; t =-5.70,P =0.000).Conclusions CBCT can help to acquire significantly more information on tumor motion than 3DCT and end-expiration phase of 4DCT,but with slightly less information than 4DCT MIP.The use of 3DCT or 4DCT registered to CBCT based on bony anatomy may still result in a serious target miss in radiotherapy,which should be focused on when we perform adaptive radiotherapy and rectify treatment planning based on CBCT.