三维适形、固定野动态调强和容积旋转调强在宫颈癌术后放疗中的剂量学比较  

Dosimetric study comparing 3D-CRT,IMRT and VMAT in postoperative radiotherapy of cervical carcinoma

作　　者：曹倩倩[1] 刘路[1] 朱丽红[1] 曲昂[1] 孙海涛[1] 姜伟娟[1] 王皓[1] 廖安燕[1] 杨瑞杰[1] 王俊杰[1] 

机构地区：[1]北京大学第三医院肿瘤放疗科,100191

出　　处：《中国妇产科临床杂志》2015年第1期15-18,共4页Chinese Journal of Clinical Obstetrics and Gynecology

摘　　要：目的宫颈癌术后放疗中,比较三维适形(CRT)、固定野调强(IMRT)和容积旋转调强(VMAT)靶区剂量分布和危及器官受照剂量,为临床治疗技术的选择提供依据。方法顺序选取北京大学第三医院2013年10例宫颈癌术后放疗的患者,分别进行CRT、IMRT和VMAT计划设计并比较计划靶区的剂量-体积直方图(DVH)、适形度指数(CI)、均匀性指数(HI)和危及器官的受照剂量。结果三种技术CI分别为0.462、0.855和0.875,IMRT和VMAT均优于CRT,VMAT较IMRT有较小的优势(P<0.05,t=-2.189);HI分别为1.084、1.063和1.046,VMAT均匀性略低于IMRT(P<0.05,t=5.127)。在危及器官的受量上,CRT普遍高于IMRT和VMAT。对于低剂量区的受照体积,如小肠、结直肠、膀胱和骨髓的V10、V20,IMRT比VMAT可以获得更低的受照剂量(P<0.05);对于高剂量区的体积V40、V50,直肠和膀胱的受照体积IMRT要小于VMAT(P<0.05),其他如小肠、结肠和股骨头、骨髓的IMRT和VMAT差异无统计学意义(P>0.05)。结论对于宫颈癌术后放疗的患者,CRT、IMRT和VMAT均可以达到靶区处方剂量覆盖的要求,但是在靶区的各项指标中,IMRT和VMAT均优于CRT。IMRT和VMAT相比,在HI上有优势,但是在CI指数上略小于VMAT;对于危及器官而言,低剂量体积和高剂量体积的IMRT和VMAT各自表现了不同的特点,在临床治疗中要根据要求选择不同的技术。Objective To compare and analyze the dose distribution and protection for organ at risk （OAR） of three- dimensional conformal radiotherapy （3D- CRT）, intensity- modulated radiation therapy （IMRT） and volumetric modulated arc therapy （VMAT） in the postoperative radiotherapy of cervical carcinoma, to provide a more effective and safe mode clinidally. Methods 3D- CRT, IMRT and VMAT plans were generated in 10 consec- utive patients with cervical cance who underwent srugery in Peking University Third Hospital during 2013. The three techniques were then compared using dose volume histogram （DVH） analysis, the conformal index （CI）, homogeneity index （HI） and dose of OAR. Results Compared with CRT, the CI of IMRT and VMAT were both improved, which showed 0. 462, 0. 855 and 0. 875, respectively, and VMAT was better than IMRT （P〈0. 05, t=- 2. 189） statistically. While the HI of the three techniques were 1. 084, 1. 063 and 1. 046, respectively, and VMAT was poorer than IMRT （P〈0. 05, t=5. 127）. As to the dose delivered to OAR, CRT was more serious than IMRT and VMAT. For low dose rate volume, as to the V10, V20 of small intestine, colorectum, bladder and bone marrow IMRT carried less doses than VMAT （P〈0. 05）. For high dose rate volume, as to V40 and V50, IMRT technique carried less doses reaching rectum and bladder. Other OARs, such as small intestine, colon, femo- ral heads and bone marrow seemed the same as IMRT and VMAT （P〉0.05）. Conclusions All the three techniques could covered the PTV correctly, IMRT and VMAT are superior than CRT in many indexes. Compared withVMAT, IMRT has advantage in HI while disadvantage in CI. For OARs, both IMRT and VMAT gained special characteristics as to low and high dose rate, which in turn shows differences in clinic.

关 键 词：宫颈癌 容积旋转调强 固定野调强 剂量学 危及器官 不良反应 

分 类 号：R737.33[医药卫生—肿瘤]