Dosimetric comparison among volumetric modulate arc therapy plans with different fluence smoothing in the treatment of patients with middle and upper thoracic esophageal carcinoma
10.3760/cma.j.issn.0254-5098.2020.01.005
- VernacularTitle: 通量平滑度在胸中上段食管癌容积弧形调强中的剂量学比较
- Author:
Fan WU
1
;
Min LIU
;
Shengwei KANG
;
Pei WANG
;
Jie LI
;
Bin TANG
;
Junxiang WU
Author Information
1. Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Radiation Oncology Key Laboratory of Sichuan Province, Chengdu 610041, China
- Publication Type:Journal Article
- Keywords:
Dosimetry;
Monaco;
Middle-upper esophageal carcinoma;
Fluence smoothing;
VMAT
- From:
Chinese Journal of Radiological Medicine and Protection
2020;40(1):32-35
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To compare the dosimetric differences of volumetric modulated arc therapy (VMAT) plans optimized with 3 different fluence smoothing parameters using Monaco treatment planning system.
Methods:A total of 15 patients with middle and upper esophageal carcinoma were planned with Low fluence smoothing (Low), Medium fluence smoothing (Medium) and High fluence smoothing(High) during VMAT optimization. The dosimetric differences in D95, Dmean, conformity index (CI), homogeneity index (HI) of targets, dose volume histogram (DVH) of organs at risk (OARs), and monitor unit (MU) were compared.
Results:There were no significant differences in D95, Dmean, CI and HI of targets, as well as in V40 and Dmean of the heart, V10, V20 and Dmean of the lung , and segment number among plans optimized with different fluence smoothing techniques (P>0.05). Plans with high fluence smoothing achieved less V30 of heart, Dmax of cord PRV(t=-2.167, -0.999, P<0.05), lower MU (t=-3.148, -6.692, P<0.05), but increased V5 of both lungs (t=1.306, -2.027, P<0.05) compared with plans with Medium and Low fluence smoothing. Plans with low fluence smoothing irradiated higher dose to the V30 and Dmean to heart (t=0.411, 0.589, 0.013, P<0.05), but less V5 of the lungs (t=0.423, P<0.05) compared with plans with medium fluence smoothing.
Conclusions:All VMAT plans with 3 different fluence smoothing can meet the clinical requirements. VMAT plans optimized with high fluence smoothing are recommended in the treatment of patients middle and upper thoracic esophageal carcinoma.
