CAJ | 학술논문

目的比较自由呼吸状态下根据四维CT (4DCT)勾画的食管癌整体与各椎体水平食管癌层面靶区外扩范围的差异.方法 13例食管癌患者接受4DCT模拟定位扫描,以呼气末TO时相为基准由同一位放疗医生在计划系统中勾画10个呼吸时相食管癌原发肿瘤体积,分别记录各时相靶区中心坐标.然后根据食管癌毗邻的同水平椎体(上下缘和中心层面)勾画10个呼吸时相CT横断面靶区,获得中心坐标(x,y)和左右、前后方向最大径.参考同一椎体平面食管癌靶区中心坐标和直径变化计算内靶区左右、前后方向外扩距离,然后筛选出10组数据中的同方向最大值,比较三维方向呼吸运动位移、相关性以及食管癌整体与分层面内靶区外扩距离差异.结果食管癌整体左右、前后、上下方向的运动范围分别为1.32、1.09、2.92 mm,其中左右与前后方向相似(t=1.21,P=0.251),左右与上下方向不同(t=-3.38,P=0.005),前后与上下方向也不同(t=-4.02,P=0.002);r值分别为0.597、0.662、0.723,P值分别为0.040、0.019、0.008.食管癌整体左、右、前、后方向平均位移分别为-0.38、0.94、-0.62、0.47 mm,按照椎体水平食管癌各分层最大位移平均值分别为-1.83、2.21、-1.85、2.02 mm,各方向比较均不同(t=5.15、-4.58、3.50、-7.56,P=0.000、0.001、0.004、0.000).结论食管癌在三维方向位移有显著相关性,根据食管癌整体测量的内靶区外扩距离显著小于分层面测量所需的最大外扩距离.
목적 비교자유호흡상태하근거사유CT (4DCT)구화적식관암정체여각추체수평식관암층면파구외확범위적차이.방법 13례식관암환자접수4DCT모의정위소묘,이호기말TO시상위기준유동일위방료의생재계화계통중구화10개호흡시상식관암원발종류체적,분별기록각시상파구중심좌표.연후근거식관암비린적동수평추체(상하연화중심층면)구화10개호흡시상CT횡단면파구,획득중심좌표(x,y)화좌우、전후방향최대경.삼고동일추체평면식관암파구중심좌표화직경변화계산내파구좌우、전후방향외확거리,연후사선출10조수거중적동방향최대치,비교삼유방향호흡운동위이、상관성이급식관암정체여분층면내파구외확거리차이.결과식관암정체좌우、전후、상하방향적운동범위분별위1.32、1.09、2.92 mm,기중좌우여전후방향상사(t=1.21,P=0.251),좌우여상하방향불동(t=-3.38,P=0.005),전후여상하방향야불동(t=-4.02,P=0.002);r치분별위0.597、0.662、0.723,P치분별위0.040、0.019、0.008.식관암정체좌、우、전、후방향평균위이분별위-0.38、0.94、-0.62、0.47 mm,안조추체수평식관암각분층최대위이평균치분별위-1.83、2.21、-1.85、2.02 mm,각방향비교균불동(t=5.15、-4.58、3.50、-7.56,P=0.000、0.001、0.004、0.000).결론 식관암재삼유방향위이유현저상관성,근거식관암정체측량적내파구외확거리현저소우분층면측량소수적최대외확거리.
Objective To evaluate the difference of esophageal cancer internal margin expansion measured by conlouring the overall or stratified GTVs parallel to the　top , bottom and center level of adjacent vertebra based on 4DCT. Methods Based on T1 phase of 4DCT scanned for 13 patients with esophageal cancer, an radiation oncologist contoured the gross tumor volumes of 10 respiratory phases in treatment planning system, the center coordinates of target volumes were recorded. Then according to the top,bottom and center level of adjacent vertebra, target volumes on multiple CT slices of 10 respiratory phases were contoured, the center coordinates (x, y) and maximum diameters of GTVs were recorded. Internal margins of multiple esophageal cancer layers contoured according to theadjacent vertebra were calculated by the formula:IM = x(y) 'T1-T10 - x(y) Ti ± (d T1－T10 - dT1 ) ,then the maximum IM of the same direction were filtered. The relationship of three dimensional movement of esophageal cancer and the difference of internal margin expansion measured by the whole or layers of esophageal cancer were analyzed . Results The motion range of the whole esophageal cancer was 1. 32 mm in left-right (x-axis) direction , 1. 09 mm in anterior-posterior (y-axis) direction, and 2. 92 mm in cranial-caudal (z-axis) direction. It was similar in x and y directions (t = 1. 21,P = 0. 251) , but different in x and zdirections (t = - 3. 38, P = 0. 005) , and different in y and z directions ( t = - 4. 02 , P = 0. 002) . There were significant relationship between motion range in x and y directions ( r = 0. 597 ,P = 0. 040) , in x and z directions ( r = 0. 662 , P = 0. 019) and in y and z directions ( r = 0. 723 , P = 0. 008). The mean movement of whole esophageal cancer in left, right,anterior and posterior was - 0. 38 ,0. 94 , - 0. 62 and 0. 47 mm, respectively; the mean maximum movement of esophageal cancer layers according to adjacent vertebra level was - 1. 83 , 2. 21 , - 1. 85 and 2. 02 mm ,respectively. There were significant differences of internal margin expansion by overall or stratified measurement of esophageal cancer in left , right , anterior and posterior dimensions ( t = 5. 15 , - 4. 58 ,3. 50 ,- 7. 56 , P = 0. 000 , 0. 001 , 0. 004 ,0. 000 ) . Conclusions There was significant relationship between motion range in thee dimensions, internal margin expansion measured by the overall esophageal cancer was less than that by stratified measurement.