Dosimetric comparison of jaw tracking technique with static jaw technique in intensity-modulated radiotherapy for preoperative radiotherapy of rectal cancer
10.3760/cma.j.issn.0254-5098.2014.12.018
- VernacularTitle:铅门跟随技术与铅门固定技术在直肠癌术前调强放疗中的剂量学比较
- Author:
Zhongsu FENG
;
Hao WU
;
Fan JIANG
;
Zhuolun LIU
;
Jinsheng CHENG
;
Xu SU
- Publication Type:Journal Article
- Keywords:
Jaw tracking;
Static jaw;
Rectal cancer;
Intensity-modulated radiation therapy;
Dosimetry
- From:
Chinese Journal of Radiological Medicine and Protection
2014;34(12):938-941
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the dosimetric difference between jaw tracking technique (JTT) and static jaw technique (SJT) in dynamic intensity-modulated radiotherapy (IMRT) for preoperative radiotherapy of rectal cancer patients.Methods Jaw tracking and static jaw were used to develope the intensity-modulated plans for 10 patients respectively.For all the patients,the dose to surrounding tissues was minimized as low as possible,the 95％ volume of the planning target volume (PTV) and planning gross target volume (PGTV) satisfy the prescribed dose.The doses of the planning target volumes,organs at risk and normal tissue were detected by dose-volume histogram.Two groups of treatment plan dose were verified by ionization chamber array 2D-Array 729 and OCTAVIUS (PTW) phantom.Results The treatment plans of two groups could satisfy the clinical requirements.There was no significant difference between the maximum and the mean dose of target.The volumes of jaw tracking dynamic intensity-modulated radiotherapy were lower,including the V5,V10,V20,V30,V40 (volumes receiving 5,10,20,30 and 40 Gy,respectively),mean dose(D) for body and V10,V20,V30,D for bilateral femoral head,bladder,and small intestine.There was significant difference for the results (t =-2.32-12.24,P ＜0.05).The verification results showed that the treatment plans were all passed the dosimetric verification.Conclusions Jaw tracking intensity-modulated radiotherapy and jaw fixed IMRT plan could achieve equal dose coverage in patients with rectal cancer,while jaw tracking techniques could reduce normal tissue dose and organs at risk dose.
