Study of feasibility of exchanging intensity-modulated radiotherapy plans after beam matching on two Linacs
Fang Chunfeng1, Xu Shouping2, Hou Jun1, Song Yuanyuan1, Xu Wei2, Cao Lin1, Yang Tao2, Wang Zishen1, Xie Dong1, Zhu Longlin1, Qu Baolin2
1Department of Radiation Oncology, Hebei Yizhou Cancer Hospital, Zhuozhou 072750, China; 2Department of Radiation Oncology, the First Medical Center of PLA General Hospital, Beijing, 100853, China
Abstract：Objective To explore the feasibility of the clinical implementation of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans with 6MV photon on two Elekta Linacs (Versa HD and Synergy) after beam matching. Methods The images of 12 patients with nasopharyngeal carcinoma, central lung cancer and prostate cancer were randomly selected, and the IMRT and VMAT plans were designed. Two different dose tools of ionization chamber and three-dimensional detector ArcCheck were used to verify the individualized radiation treatment of 6MV photon beams on two Linacs and compare the differences. Results The deviations between the doses of two Linacs (Versa HD and Synergy) measured by the ion chamber and treatment planning system were (0.32±1.32)% and (0.54±1.29)%. The differences of all plans were within the range of ±3%, and the deviations of the point dose between two Linacs were within the range of ±2% with no statistical significance (both P>0.05). The γ analysis of verification using ArcCheck showed that the passing rates of all plans under the 2mm/3% and 3mm/3% with 10% threshold conditions were over 95%, respectively. The average differences between two Linacs were 0.19%(2mm/3%) and 0.09%(3mm/3%). Conclusions The results of performing IMRT/VMAT plans on two Linacs meet the clinical requirements and the differences between two Linacs are small. Hence, the same plans can be implemented interchangeably on different Linacs.
Fang Chunfeng,Xu Shouping,Hou Jun et al. Study of feasibility of exchanging intensity-modulated radiotherapy plans after beam matching on two Linacs[J]. Chinese Journal of Radiation Oncology, 2021, 30(7): 702-706.
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2021, Vol. 30 
