PMID- 32969046 OWN - NLM STAT- MEDLINE DCOM- 20210514 LR - 20210514 IS - 2473-4209 (Electronic) IS - 0094-2405 (Linking) VI - 47 IP - 11 DP - 2020 Nov TI - Evaluation of differences and dosimetric influences of beam models using golden and multi-institutional measured beam datasets in radiation treatment planning systems. PG - 5852-5871 LID - 10.1002/mp.14493 [doi] AB - PURPOSE: The beam model in radiation treatment planning systems (RTPSs) plays a crucial role in determining the accuracy of calculated dose distributions. The purpose of this study was to ascertain differences in beam models and their dosimetric influences when a golden beam dataset (GBD) and multi-institution measured beam datasets (MBDs) are used for beam modeling in RTPSs. METHODS: The MBDs collected from 15 institutions, and the MBDs' beam models, were compared with a GBD, and the GBD's beam model, for Varian TrueBeam linear accelerator. The calculated dose distributions of the MBDs' beam models were compared with those of the GBD's beam model for simple geometries in a water phantom. Calculated dose distributions were similarly evaluated in volumetric modulated arc therapy (VMAT) plans for TG-119 C-shape and TG-244 head and neck, at several dose constraints of the planning target volumes (PTVs), and organs at risk. RESULTS: The agreements of the MBDs with the GBD were almost all within +/-1%. The calculated dose distributions for simple geometries in a water phantom also closely corresponded between the beam models of GBD and MBDs. Nevertheless, there were considerable differences between the beam models. The maximum differences between the mean energy of the energy spectra of GBD and MBDs were -0.12 MeV (-10.5%) in AcurosXB (AXB, Eclipse) and 0.11 MeV (7.7%) in collapsed cone convolution (CCC, RayStation). The differences in the VMAT calculated dose distributions varied for each dose region, plan, X-ray energy, and dose calculation algorithm. The ranges of the differences in the dose constraints were -5.6% to 3.0% for AXB and -24.1% to 2.8% for CCC. In several VMAT plans, the calculated dose distributions of GBD's beam model tended to be lower in high-dose regions and higher in low-dose regions than those of the MBDs' beam models. CONCLUSIONS: We found that small differences in beam data have large impacts on the beam models, and on calculated dose distributions in clinical VMAT plan, even if beam data correspond within +/-1%. GBD's beam model was not a representative beam model. The beam models of GBD and MBDs and their calculated dose distributions under clinical conditions were significantly different. These differences are most likely due to the extensive variation in the beam models, reflecting the characteristics of beam data. The energy spectrum and radial energy in the beam model varied in a wide range, even if the differences in the beam data were <+/-1%. To minimize the uncertainty of the calculated dose distributions in clinical plans, it was best to use the institutional MBD for beam modeling, or the beam model that ensures the accuracy of calculated dose distributions. CI - (c) 2020 American Association of Physicists in Medicine. FAU - Tani, Kensuke AU - Tani K AD - Division of Medical Physics, EuroMediTech Co., LTD., Shinagawa, Tokyo, 141-0022, Japan. FAU - Wakita, Akihisa AU - Wakita A AD - Division of Medical Physics, EuroMediTech Co., LTD., Shinagawa, Tokyo, 141-0022, Japan. FAU - Tohyama, Naoki AU - Tohyama N AD - Division of Medical Physics, Tokyo Bay Advanced Imaging and Radiation Oncology Makuhari Clinic, Chiba, Chiba, 261-0024, Japan. FAU - Fujita, Yukio AU - Fujita Y AD - Department of Health Sciences, Komazawa University, Setagaya, Tokyo, 154-8525, Japan. FAU - Kito, Satoshi AU - Kito S AD - Department of Radiotherapy, Tokyo Metropolitan Bokutoh Hospital, Sumida, Tokyo, 130-8575, Japan. AD - Division of Medical Physics, Graduate School of Medicine, Kyoto University, Sakyo, Kyoto, 606-8507, Japan. FAU - Miyasaka, Ryohei AU - Miyasaka R AD - Department of Radiation Oncology, Chiba Cancer Center, Chiba, Chiba, 260-8717, Japan. FAU - Mizuno, Norifumi AU - Mizuno N AD - Department of Radiation Oncology, St. Luke's International Hospital, Chuo, Tokyo, 104-8560, Japan. FAU - Uehara, Ryuzo AU - Uehara R AD - Department of Radiation Oncology, National Cancer Center Hospital East, Kashiwa, Chiba, 277-8577, Japan. FAU - Takakura, Toru AU - Takakura T AD - Department of Radiation Oncology, Uji-Tokushukai Medical Center, Uji, Kyoto, 611-0041, Japan. FAU - Miyake, Shunsuke AU - Miyake S AD - Department of Radiation Oncology, Yamato Takada Municipal Hospital, Yamatotakada, Nara, 635-8501, Japan. FAU - Shinoda, Kazuya AU - Shinoda K AD - Department of Radiation Oncology, Ibaraki Prefectural Central Hospital, Kasama, Ibaraki, 309-1793, Japan. FAU - Oka, Yoshitaka AU - Oka Y AD - Department of Radiation Oncology, Fukushima Medical University Hospital, Fukushima, Fukushima, 960-1295, Japan. FAU - Saito, Yasunori AU - Saito Y AD - Department of Radiology, Fujita Health University Hospital, Toyoake, Aichi, 470-1192, Japan. FAU - Kojima, Hideki AU - Kojima H AD - Department of Radiation Oncology, Sapporo Higashi Tokushukai Hospital, Sapporo, Hokkaido, 065-0033, Japan. FAU - Hayashi, Naoki AU - Hayashi N AD - School of Medical Sciences, Fujita Health University, Toyoake, Aichi, 470-1192, Japan. LA - eng PT - Journal Article DEP - 20201015 PL - United States TA - Med Phys JT - Medical physics JID - 0425746 SB - IM MH - Algorithms MH - Organs at Risk MH - Radiometry MH - Radiotherapy Dosage MH - *Radiotherapy Planning, Computer-Assisted MH - *Radiotherapy, Intensity-Modulated OTO - NOTNLM OT - RTPS OT - beam model OT - golden beam data EDAT- 2020/09/25 06:00 MHDA- 2021/05/15 06:00 CRDT- 2020/09/24 05:37 PHST- 2020/06/12 00:00 [received] PHST- 2020/08/19 00:00 [revised] PHST- 2020/09/08 00:00 [accepted] PHST- 2020/09/25 06:00 [pubmed] PHST- 2021/05/15 06:00 [medline] PHST- 2020/09/24 05:37 [entrez] AID - 10.1002/mp.14493 [doi] PST - ppublish SO - Med Phys. 2020 Nov;47(11):5852-5871. doi: 10.1002/mp.14493. Epub 2020 Oct 15.