Dosimetric comparison of three dimensional conformal radiotherapy and simplified intensity modulated radiotherapy for middle-third esophageal cancer
10.3969/j.issn.1002-3070.2014.02.009
- VernacularTitle:胸中段食管癌三维适形放疗与简化调强放疗技术的剂量学比较
- Author:
Yuanyuan ZHOU
;
Sixing ZHANG
;
Qingping ZHENG
;
Chengliang SHI
;
Zhanxiong LUO
;
Jing LI
;
Bin YU
;
Zhonghua LI
- Publication Type:Journal Article
- Keywords:
Middle-third esopheagal cancer;
Three dimensional conformal radiotherapy;
Simplified in-tensity modulated radiotherapy;
Dosimetric comparison
- From:
Practical Oncology Journal
2014;(2):140-143
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the dose distribution between three dimensional conformal radiothera -py(3DCRT) and simplified intensity modulated radiotherapy ( sIMRT) for middle-third esopheagal cancer .Meth-ods Twenty middle-third esopheagal cancer patients were enrolled in this study .Dosimetric values for sIMRT and 3DCRT were calculated for total dose of 66 Gy using 2 Gy/day.The parameters included the conformal index (CI),homogeneity index(HI),mean dose and hot spot(V105%)for the planned target volume(PTV)as well as the monitor units(MUs)for plan efficiency,the mean dose(Dmean)for the organs at risk(OAR).The percentage of the normal lung volume receiving≥30,>20 and >5 Gy(V30 Gy,V20 Gy and V5 Gy)were evaluated to deter-mine lung toxity.Results sIMRT achieved significant better Dmin ,Dmean,V105%,HI,CI and spinal cord than 3DCRT(P<0.05).The normal lung V30 Gy and V20 Gy of 3DCRT and sIMRT were 11.61 ±3.68 vs.10.33 ± 3.02(P=0.010)and 23.37 ±8.38 vs.18.89 ±4.45(P=0.001),respectively.Comparable sparing of normal tissue including heart and the normal lung V 5 Gy with both two plans .The number of MU was 542 .24 ±76 .32 for 3DCRT and 530.8 ±97.13 for sIMRT(P=0.677).Conclusion sIMRT provides favorable tumor coverage , homogeneity and conformity and can get better normal lung sparing than 3DCRT.However sIMRT is not superior to 3DCRT in terms of treatment efficiency .
