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宫颈癌术后盆腔容积调强弧形治疗与固定野调强放疗计划的剂量学研究
杨波, 庞廷田, 孙显松, 胡克, 邱杰, 张福泉
100730 北京,北京协和医学院 中国医学科学院北京协和医院放疗科
Dosimetric study of volumetric intensity-modulated arc therapy and fixed field intensity-modulated radiotherapy for cervix cancer
YANG Bo,PANG Ting-tian, SUN Xian-song, HU Ke, QIU Jie, ZHANG Fu-quan
Department of Radiotherapy, Peking Union Hospital, Chinese Academy of Medical Sciences, Pecking Union Medical College, Beijing 100730, China
Corresponding author:QIU Jie, Email:qiujie@yahoo.cn
Objective To compare the dosimetry characteristics of volumetric intensity-modulated arc therapy (VIMAT) and fixed field intensity-modulated radiation therapy (FF-IMRT) for cervix cancer. Methods CT images of 13 patients with cervix uteri cancer were transferred into Eclipse planning system. FF-IMRT and VIMAT plans were optimized on an Eclipse treatment planning system using beam data generated for Varian trilogy linear accelerator. Planning target volume (PTV) and organs at risk were evaluated with dose-volume histogram. To appraise the difference between the techniques, the paired t-test was applied.Results Compared with the FF-IMRT plans, PTV95% coverage of VIMAT plan group increased (t=9.84,P=0.000), PTV110% became lower (t=-3.72,P=0.003), Dmax decreased (t=-3.51,P=0.005), and CI became worser (t=5.39,P=0.000). PTV105%, Dmean, and HI had no difference (t=-0.02,-0.60,1.13,P=0.842,0.560,0.283). V30 of the bladder was reduced by about 10%(t=-4.99,P=0.000), and Dmean and Dmax were 1.4 Gy and 1.5 Gy lower respectively (t=-3.65,-18.03,P=0.004, 0.000);V40 of the rectum was reduced by about 10%(t=-2.99,P=0.012), and Dmean and Dmax were reduced by 0.6 Gy, 0.8 Gy respectively (t=-2.98,-4.05,P=0.013,0.002);V30, V40 and V50 of the small intestine were reduced by 16%, 10% and 11%(t=-10.85,-4.74,-8.66,P=0.000, 0.001, 0.000), and Dmax was reduced by 0.8 Gy (t=-9.45,P=0.000);V30, V40 and V50 of the bone marrow were reduced by 26%, 19% and 16%(t=-22.10,-10.19,-4.04,P=0.000, 0.000,0.002),and Dmean reduced by 1.9 Gy (t=-16.21,P=0.000);D5 of the left and right femoral heads were reduced by 1.6 Gy and 2.7 Gy (t=-2.89,-6.22,P=0.015,0.000). Dmax of the caudate equine wasreduced by 1.5 Gy (t=-4.80,P=0.001).V20, V30, V40 and V50 of the body were reduced by 18%, 18%, 4% and 3%(t=-7.52,-11.75,-6.26,-6.94,P=0.000, 0.000, 0.000, 0.000). Dmean and Dmax of the body decreased by 1.0 Gy and 0.4 Gy (t=-3.72,-3.51,P=0.000, 0.005). Average machine unit (MU) decreased by 57%(t=-40.54,P=0.000).Conclusions cervical cancer Patients with VIMAT technology can get equivalent or superior dose distribution compared with the FF-IMRT technology. And VIMAT technology could reduce MU. But the efficacy needs further clinical evaluation
YANG Bo,PANG Ting-tian,SUN Xian-song et al. Dosimetric study of volumetric intensity-modulated arc therapy and fixed field intensity-modulated radiotherapy for cervix cancer[J]. Chinese Journal of Radiation Oncology, 2012, 21(6): 543-545.
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