宫颈癌IGRT+ICBT治疗中器官体积对剂量分布的影响研究  

Effects of Organ Volume on Dosage Distribution in IGRT and ICBT for Cervical Cancer

作　　者：赵凤菊[1] 陶发利 郭晴 安永伟[1] 唐红[1] 罗莉[1] 谭燕 Zhao Fengju;Tao Fali;Guo Qing;An Yongwei;Tang Hong;Luo Li;Tan Yan(Department of Radiotherapy、Gansu Cancer Hospital,Lanzhou 730050,Gansu,China;Radiotherapy Center,Sichuan Cancer Hospital&In-stitute,Sichuan Cancer Center,School of Medicine,University of Electronic Science and Technology of China,Chengdu 610041,Sichuan,China)

机构地区：[1]甘肃省肿瘤医院放疗科,兰州730050 [2]四川省肿瘤医院·研究所,四川省癌症防治中心,电子科技大学医学院放疗中心,成都610041

出　　处：《肿瘤预防与治疗》2021年第9期831-837,共7页Journal of Cancer Control And Treatment

摘　　要：目的:研究宫颈癌图像引导调强放射治疗(image guided radiation therapy,IGRT)同步剂量补偿腔内后装治疗(intracavitary brachytherapy,ICBT)中膀胱、直肠、高危临床粑区(high risk clinical target volume,HRCTV)和中危临床耙区(imermediate risk clinical target volume,1RCTV)体积对器官受照剂量的影响。方法:回顾性分析64例根治性宫颈癌患者数据,每位患者至少接受了2次IGRT+ICBT,处方剂量HRCTVD90%=600cGy,IRCTVD90%=500cGy,分别按照膀胱、直肠、HRCTV、IRCTV的体积将患者数据分为高、低两组,统计这两组数据的靶区Dmin、D_(90%),危及器官的热点剂量(D_(0.1cm3)、D_(1cm3)和D_(2cm2))和D_(50%),采用统计学软件分析器官体积对剂量分布的影响。结果:靶区的Dmin和D90%均不受膀胱、直肠体积的影响。增加膀胱体积会明显地增加膀胱的热点剂量,但是未明显降低膀胱D_(50%)。膀胱体积的改变不影响直肠的受照剂量。小肠的受照剂量随着膀胱体积的增加而减小。高体积组直肠的热点剂量明显高于低体积组(P<0.001),不过两组之间直肠D50%的改变不明显。增加靶区的体积并不会明显降低靶区的最小剂量Dmin,随着靶区体积的增加,膀胱、直肠的D50%都有显著增加。结论:宫颈癌IGRT+ICBT治疗中膀胱体积增大会增加膀胱的热点剂量,但可以降低小肠的热点剂量,建议根据不同患者保护不同器官的需要,选择合适的膀胱充盈程度。直肠应始终处于排空状态,以减小直肠所受的照射剂量。Objective:To study the influence of bladder volume,rectum volume,high risk clinical target volume(HRCTV)and intermediate-risk clinical target volume(IRCTV)on radiation dosage to organs in image-guided radiation therapy(IGRT)plus intracavitary brachytherapy(ICBT)for cervical cancer.Methods:Data of 64 patients with radical cer-vical cancer were retrospectively analyzed.Each patient received IGRT plus ICBT for 2 times,with dosage prescriptions of D_(90%)=600 cGy(HRCTV)and D%=500 cGy(IRCTV).The data were assigned to high and low groups according to bladder volume,rectum volume,HRCTV and IRCTV.We collected target D。in and D_(90%),as well as hotspot dosages(D_(0.1cm3),D_(1cm3) and D2cm3)and D50%of organs at risk.Statistical software was used to analyze the effects of organ volume on dosage distribution.Results:Neither bladder volume nor rectum volume had effect on target Dmin and.The hotspot dosage to bladder significantly increased as bladder volume increased;the bladder D_(50%),however,did not decreased with the increase of bladder volume.Changes in bladder volume did not affect the radiation dosage to rectum.The radiation dosage to intestines decreased with the increase of bladder volume.The hotspot dosage to rectum in the high volume group was significantly higher than that in the low volume group(P<0.001).Changes in rectum D50%in both groups were not significant.The Dmin of the target did not decrease as the target volume increased;the D_(50%) of bladder and rectum,however,increased significantly with the increase of target volume.Conclusion:In the treatment of cervical cancer by IGRT and ICBT,the hotspot dosage to bladder will increase with the increase of bladder volume,but the hotspot dosage to intestines will decrease accordingly.Bladder filling should be properly controlled to protect patients*organs.The rectum should always be empty to reduce the radiation dosage to the rectum.

关 键 词：图像引导调强放射治疗 腔内后装治疗 宫颈癌 器官体积 剂量 

分 类 号：R737.33[医药卫生—肿瘤]