Dosimetric comparison of three-dimensional conformal radiotherapy,intensity-modulated radiotherapy and RapidArc in treatment of thoracic esophageal cancer
10.3760/cma.j.issn.0254-5098.2012.01.016
- VernacularTitle:三维适形、逆向调强和旋转调强放疗技术治疗胸段食管癌的剂量学比较
- Author:
Yanli YANG
;
Baosheng LI
;
Yong YIN
;
Jinhu CHEN
;
Tao SUN
;
Hongfu SUN
- Publication Type:Journal Article
- Keywords:
Thoracic esophageal cancer;
Dosimetric parameter;
Three-dimensional conformal radiotherapy;
Intensity-modulated radiotherapy;
Volumetric modulated arc radiotherapy
- From:
Chinese Journal of Radiological Medicine and Protection
2012;32(1):65-69
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the dosimetric characteristics of intensity-modulated arc therapy( IMAT ),fixed-gantry intensity-modulated radiotherapy ( IMRT ) and 3-dimensional conformal radiotherapy (3D-CRT) for the thoracic esophageal cancer.Methods A total of 15 patients with thoracic esophageal cancer were enrolled.3D-CRT,5-field IMRT( IMRT5 ),7-field IMRT( IMRT7 ),9-field IMRT ( IMRT9 ),single arc ( Arc1 ) and double arc ( Arc2 ) RapidArc plans were generated for each patient.All plans were prescribed 40 Gy in 20 fractions and 19.6 Gy in 14 fractions to PTV at 95％ isodose line.Results RapidArc and all IMRT treatment plans in dosimetric parameters of target volumes were obviously better compared to 3-dimentional conformal treatments( t =5.77,3.52,P ＜ 0.05 ).The result of V95 of PTV for 3D-CRT,IMRT5,IMRT7,IMRT9,Arc1 and Arc2 plans was 91.55 ±2.90,96.66 ±1.05,96.87 ± 1.23,96.81 ± 1.16,94.98 ± 1.41 and 95.93 ± 1.32,respectively.The best conformation index in PTV was observed in the RapidArc plans ( t =3.76,10.01,P ＜ 0.05 ),and the best homogeneity index in PTV was observed in the IMRT plans( t =3.93,3.37,P ＜ 0.05 ).In terms of organ sparing,no statistical difference was observed between IMRT and RapidArc plans( P ＞ 0.05 ),while 3D-CRT provided the lowest number of V1 cGy and V5 cGy for total lung.Compared with the IMRT treatment plans,the number of monitor units was lower in all 3D-CRT and RapidArc cases with differences of 75％.Conclusions All the IMRT and RapidArc plans could offer high quality treatment for patients.3D-CRT might show advantage in low-dose region to organs at risk.Compared with IMRT,no obvious advantage in PTV dosimetric parameters could be observed in RapidArc plans.
