Dosimetric comparison of helical tomotherapy and volume-modulated arc therapy for upper thoracic esophageal carcinoma
10.3760/cma.j.issn.0254-5098.2016.01.011
- VernacularTitle:胸上段食管癌螺旋断层放疗和容积旋转调强放疗的剂量学比较
- Author:
Xiangkun DAI
;
Boning CAI
;
Ruigang GE
;
Xiaoshen WANG
;
Yunlai WANG
- Publication Type:Journal Article
- Keywords:
Esophageal neoplasms;
Helical tomotherapy;
Volume-modulated arc therapy;
Dosimetry
- From:
Chinese Journal of Radiological Medicine and Protection
2016;36(1):58-62
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the dosimetric differences between helical tomotherapy (HT) and volume-modulated arc therapy (VMAT) in the treatment of upper thoracic esophageal carcinoma (UTEC).Methods A total of 10 patients with UTEC were randomly selected.HT plan and double-arc VMAT plan were designed and optimized for each patient.The prescription dose was 50 Gy/30 fractions for gross target volume (GTV), 66 Gy/30 fractions for planned target volume (PTV).The dose distribution and conformal index (CI), homogeneity index (HI) of target volume, the D1%, D5%, Dg5%, D99%, and dose of organ at risk (OAR) were analyzed by using the dose volume histogram (DVH).The monitor units and delivery time were also evaluated.Results For GTV and PTV, the D99% of HT plans were slightly higher than those of VMAT plans (t =4.476, 3.756, P < 0.05) , but no significant differences in D1% , D5% , D95% , HI and CI (P > 0.05) were found.The V10, V15, V20 and mean lung dose (MLD) to the total-lung of HT plans were all significantly lower than those of VMAT plans (t =-3.369,-4.824, -4.869,-3.657, P < 0.05).There were no significant differences for V5, V30 and Dmax of cord (P > 0.05).The monitor units and delivery time of VMAT plans were significantly lower than those of HT plans (t =13.970, 7.982, P < 0.05).Conclusions Both HT and VMAT are appropriate for esophageal cancer radiotherapy.HT significantly reduces the radiation dose of the total-lung, while VMAT has obvious advantages in efficiency.