Author: Shupeng Chen, Xiaoda Cong, Raymond Dalfsen, Rohan Deraniyagala, Xuanfeng Ding, James E. Dolan, Xiaoqiang Li, Jian Liang, Peilin Liu, An Qin, Martin Soukup, Craig Stevens, Xiangkun Xu, Weili Zheng 👨🔬
Affiliation: Corewell Health William Beaumont University Hospital, Corewellhealth William Beaumont University Hospital, William Beaumont University Hospital, Elekta, Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Corewellhealth William Beaumont Hospital, Department of Radiation Oncology, Corewell Health William Beaumont University Hospital 🌍
Purpose: To facilitate clinical use of the proton feature of Monaco treatment planning system(TPS), we commissioned and validated it on a compact proton therapy system.
Methods: Pencil Beam Scanning(PBS) and Monte Carlo(MC) dose calculation algorithms in Monaco TPS proton module(version6) were commissioned on the IBA ProteusONE® system. The physics model validation includes(1) Pristine Bragg peak proton range in water for mono-energetic proton beam at 10×10cm2 field size; (2)Output with standard cube plans mimicking different treatment sites and target volumes; (3)Independent End-to-End testing with IROC phantom. A patient diagnosed with basal cell carcinoma of the skin was treated with proton beam therapy to provide uniform target coverage while sparing the radiation dose to the organs-at-risk with prescribed dose of 60Gy in 30 fractions. IMPT plan with two fields, one left anterior oblique beam and one left superior posterior oblique beam, was optimized with robust optimization for 2mm setup and 3.5% range uncertainties. The plan was compared to a current clinical TPS.
Results: The deviation of distal range of 90% dose(D90) of pristine Bragg peak between Monaco TPS and measured data is within 1mm for proton energy from 70MeV to 230MeV. The output difference between the measured and Monaco TPS data among all the standard cube phantoms is less than 2%. For IROC brain phantom, the ratio of the TLD measured dose to the Monaco MC calculated dose is 1 and the gamma index on coronal and sagittal film plane is 94% and 98%, respectively. The treatment plans on real patient from the Monaco TPS and the current clinical TPS are comparable.
Conclusion: The physical beam modeling and dose calculation algorithm in Monaco proton TPS were within clinical tolerances. The first patient was successfully treated in November 2024 with the implementation of robust optimization and dose validation based on daily CBCT.