呼吸运动对肺癌治疗靶体积影响的探讨

Impact of respiratory movement on the target volume for lung cancer therapy

目的研究在肺癌放射治疗过程中呼吸运动对靶体积的影响。方法选择52例肺癌患者,其中男性38例,女性14例;年龄38～86岁,中位年龄60岁。进行三维适形放射治疗(3D-CRT)定位时通过训练患者自主控制呼吸,分别在平静呼吸吸气末屏气和呼气末屏气及不控制呼吸(平静自主呼吸)3种情况下,用螺旋CT快速扫描采集图像,将3组图像传输至计划系统,将前两组进行图像融合,勾画个体化放射治疗靶区,并与第3组不控制呼吸情况下所勾画的个体化放射治疗靶区进行靶体积比对。结果有41例成功进行图像融合,勾画出个体化放射治疗靶区。肺部病变随呼吸运动产生的靶体积变化差异有显著统计学意义(P=0.000<0.01),其中上肺野35.55%,中肺野19.17%,下肺野45.73%。结论应用CT-CT图像融合后进行靶区计划设计能有效避免在肺癌放射治疗中因呼吸运动所造成的靶区遗漏。

Objective To investigate the influence of respiration motion on the target volume during radiotherapy of lung cancer.Methods A total of 52 patients with lung cancer were enrolled,included 38 males and 14 females,who were 38-86 years old with a median ages of 60.All of them underwent computed tomography（CT） scans in three-dimensional conformal radiotherapy position,which were in 3 respiration conditions： breathing-holding at end-aspiratory,breathing-holding at end-expiratory and free breath,and the images were subsequently transferred to the treatment planning system.Images of the former 2 groups were fused and individual radiotherapy targets were delineated,which were then compared with the individual target volume of radiotherapy in the 3rd group.Results The images of forty-one patients were successfully fused and the individual radiotherapy targets were delineated.The change in the target volume of lung lesions with respiratory movement was 35.55 % in the upper lung field,19.17 % in the middle lung field and 45.73 % in the lower lung field.Conclusion It is demonstrated that designing target plan after application of CT-CT fusion image could prevent target area omission,which is caused by respiratory movement during the radiotherapy of lung cancer.