Treatment and dosimetry advantage between FF-IMRT, VMAT, and HT in cervix uteri radiotherapy / 中华放射肿瘤学杂志

ABSTRACT

Objective To investigate dosimetric advantage of fixed field intensity-modulated radiotherapy (FF-IMRT),volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT) for cervix uteri cancer.Methods CT datasets of ten patients with cervix uteri cancer were enrolled in the study.FF-IMRT,VMAT and HT plans were designed on Eclipse and HT treatment planning system.Plans were optimized with the aim to assess OAR while enforcing highly conformal target coverage.Institutional dose-volume constraints used in cervix uteri cancer were kept the same for three techniques.The different of three plan was play by single factor analysis of variance and compared to two groups by LSD method.Results All FF-IMRT,VMAT and HT resulted in equivalent target coverage but HT had an improved homogeneity index (P =0.000) and conformity index (P =0.000),or PTV of 105％ prescription dose (47.12％,45.83％ and 0.05％,P=0.000) and lowest Dmax dose (54.53 Gy,53.65 Gy,52.69 Gy,P=0.000).Compared with FF-IMRT and VMAT,the bladder V40 and Dmax of HT were lowest (50.01％,46.84％,42.98％,P=0.001 and 54.49 Gy,52.96 Gy,52.78 Gy,P=0.000),with the rectum V40 lowest (54.61％,48.34％,46.78％,P =0.006),the intestine Dmax lowest (54.53 Gy,53.65 Gy,52.66 Gy,P =0.000) and marrow Dmax lowest (54.51 Gy,54.44 Gy,52.13 Gy,P=0.000).But the delivery MU per fraction were highest (1429.20 MU,617.80 MU,7002.04 MU,P =0.000).Conclusions HT technology is feasible for clinical applications in cervical uteri cancer and can be used as a new method to promote.