中下段食管癌21例放疗不同呼吸时相正常组织剂量学研究  

Dosimetric study of normal tissues in different respiratory phases of radiotherapy in 21 patients with middle and lower esophageal carcinoma

作　　者：吕海鹏 王凯 刘晓 赵焕升 胡范祥 李翊 LYU Hai peng;WANG Kai;LIU Xiao;ZHAO Huan-sheng;HU Fan-xiang;LI Yi(De parlment of Radiothera py,Navy 971 Hospital of Chinese People's Liberation Army,Qingdao 266071,P.R.China)

机构地区：[1]中国人民解放军海军第971医院放疗科,山东青岛266071

出　　处：《中华肿瘤防治杂志》2020年第15期1241-1246,共6页Chinese Journal of Cancer Prevention and Treatment

摘　　要：目的呼吸运动可能导致胸部放疗过程中正常器官实际剂量与计划剂量不符,本研究基于普通螺旋CT探讨呼吸运动对中下段食管癌放疗中正常器官实际受照剂量的影响。方法回顾性分析2017-02-03-2017-09-28海军第971医院21例中下段食管癌放疗患者临床资料,在治疗前行平静吸气后屏息和平静呼气后屏息CT定位,分别将两时相的CT图像传输至计划系统并将两时相图像融合。在不同时相上勾画靶区和危及器官,用其中一个时相制CT图像定治疗计划,然后将计划移植到另一个时相图像,分析2个呼吸时相双肺、心脏、脊髓相关参数的变化。结果双肺受照射剂量吸气末较呼气末均有减小趋势。吸气末双肺平均剂量较呼气末小,分别为(12.33±1.66)和(14.30±1.89)Gy,P<0.05;V5、V10、V15、V20吸气末比呼气末小,其中V5分别为(52.44±6.40)%和(59.89±5.97)%,V20分别为(25.34±3.93)%和(28.36±4.15)%,均P<0.05;V25、V30变化不明显,均P>0.05;两时相V5[(14.76±8.53)%]~V30[(10.43±5.93)%]的变化率基本呈递减趋势。吸气末心脏体积为(0.57±0.02)L,较呼气末(0.60±0.02)L小,P<0.05;吸气末心脏平均剂量为(30.60±2.10)Gy,略高于呼气末的(29.39±1.66)Gy,P<0.05;吸气末与呼气末的V30差别较小,P>0.05。脊髓的体积和最大剂量受呼吸运动影响小,均P>0.05。结论中下段食管癌放疗中使用不同呼吸时相制定治疗计划双肺平均剂量及V5、V10、V15、V20变化明显,心脏平均剂量略有改变,脊髓受量变化不明显。OBJECTIVE Respiratory movement may lead to a discrepancy between the actual dose of normal organs and the planned dose during chest radiotherapy.In the study,based on the spiral CT images,the influence of respiratory movement on the actual dose of irradiated normal organs in radiotherapy of middle and lower esophageal cancer was investigated.METHODS Twenty-one cases with middle and lower esophageal cancer,which were treated in the Radiotherapy Department,Navy 971 Hospital from 3 February 2017 to 28 September 2017 were retrospectively analyzed.The spiral CT machine was adopted for simulation after quiet inhalation and quiet exhalation before treatment.The two phases of CT images were transmitted to the planning system and respectively fused with the two phases of CT images.The target areas and organs at risk in different phases were delineated,one of the phases was used to develop the treatment plans,and then the plans were transplanted to another phase image.The changes of related parameters of the lungs,heart and spinal cord in two respiratory phases were analyzed.RESULTS The irradiated doses of whole lung appeared a decreasing trend at the end of inhalation compared with those at the end of exhalation.The average doses of whole lung at the end of inhalation were lower than those at the end of exhalation,and were(12.33±1.66)Gy and(14.30±1.89)Gy,respectively,P<0.05.The V5,V10,V15and V20at the end of inhalation were lower than those at the end of exhalation.Among them,the V5and V20 were(52.44±6.40)%and(59.89±5.97)%,(25.34±3.93)%and(28.36±4.15)%,respectively,P<0.05.The changes of the V25and V30 weren’t obvious,P>0.05.The change rates of the two-phases V5-V30presented a decreasing trend,(14.76±8.53)%in V5,(10.43±5.93)%in V30.The volume of the heart at the end of inhalation was smaller than that at the end of exhalation,and were(0.57±0.02)L and(0.60±0.02)L,respectively,P<0.05.The average doses(30.60±2.10)Gy of the heart at the end of inhalation were slightly higher than those(29.39±1.66)Gy at the end of

关 键 词：食管癌 呼吸运动 心肺损伤 中下段 调强放疗 剂量学 

分 类 号：R735.1[医药卫生—肿瘤]