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Kalholm F, Toma-Dasu I, Traneus E, Bassler N. Novel radiation quality metrics accounting for proton energy spectra for RBE proton models. Med Phys 2024. [PMID: 38852194 DOI: 10.1002/mp.17236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 05/24/2024] [Accepted: 05/25/2024] [Indexed: 06/11/2024] Open
Abstract
BACKGROUND For proton therapy, a relative biological effectiveness (RBE) of 1.1 is widely applied clinically. However, due to abundant evidence of variable RBE in vitro, and as suggested in studies of patient outcomes, RBE might increase by the end of the proton tracks, as described by several proposed variable RBE models. Typically, the dose averaged linear energy transfer (LET d $\text{LET}_d$ ) has been used as a radiation quality metric (RQM) for these models. However, the optimal choice of RQM has not been fully explored. PURPOSE This study aims to propose novel RQMs that effectively weight protons of different energies, and assess their predictive power for variable RBE in proton therapy. The overall objective is to identify an RQM that better describes the contribution of individual particles to the RBE of proton beams. METHODS High-throughput experimental set-ups of in vitro cell survival studies for proton RBE determination are simulated utilizing the SHIELD-HIT12A Monte Carlo particle transport code. For every data point, the proton energy spectra are simulated, allowing the calculation of novel RQMs by applying different power levels to the spectra of LET or effective Q $Q$ (Q eff $Q_\mathrm{eff}$ ) values. A phenomenological linear-quadratic-based RBE model is then applied to the in vitro data, using various RQMs as input variables, and the model performance is evaluated by root-mean-square-error (RMSE) for the logarithm of cell surviving fractions of each data point. RESULTS Increasing the power level, that is, putting an even higher weight on higher LET particles when constructing the RQM is generally associated with an increased model performance, with dose averagedLET 3 $\text{LET}^3$ (i.e., dose averaged cubed LET,cLET d $\mathrm{cLET}_d$ ) resulting in a RMSE value 0.31, compared to 0.45 for a model based on (linearly weighted)LET d $\text{LET}_d$ , with similar trends also observed for track averaged andQ eff $Q_\mathrm{eff}$ -based RQMs. CONCLUSIONS The results indicate that improved proton variable RBE models can be constructed assuming a non-linear RBE(LET) relationship for individual protons. If similar trends hold also for an in vitro-environment, variable RBE effects are likely better described bycLET d $\mathrm{cLET}_d$ or tracked averaged cubed LET (cLET t $\mathrm{cLET}_t$ ), or correspondingQ eff $Q_\mathrm{eff}$ -based RQM, rather than linearly weightedLET d $\text{LET}_d$ orLET t $\text{LET}_t$ which is conventionally applied today.
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Affiliation(s)
- Fredrik Kalholm
- Medical Radiation Physics, Department of Physics, Stockholm University, Stockholm, Sweden
- Department of Oncology and Pathology, Medical Radiation Physics, Karolinska Institutet, Stockholm, Sweden
| | - Iuliana Toma-Dasu
- Medical Radiation Physics, Department of Physics, Stockholm University, Stockholm, Sweden
- Department of Oncology and Pathology, Medical Radiation Physics, Karolinska Institutet, Stockholm, Sweden
| | | | - Niels Bassler
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
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2
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Gao RW, Ma J, Pisansky TM, Kruse JJ, Stish BJ, Kowalchuk RO, McMenomy BP, Waddle MR, Phillips RM, Choo R, Davis BJ. Dosimetric Features of Ultra-Hypofractionated Intensity Modulated Proton Therapy for Prostate Cancer. Int J Part Ther 2024; 12:100015. [PMID: 38827121 PMCID: PMC11137510 DOI: 10.1016/j.ijpt.2024.100015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/08/2024] [Accepted: 03/06/2024] [Indexed: 06/04/2024] Open
Abstract
Purpose To report clinical and dosimetric characteristics of 5-fraction stereotactic ablative radiotherapy (SABR) using intensity modulated proton therapy (IMPT) for localized prostate cancer. Materials and Methods All patients receiving IMPT SABR from 2017 to 2021 for localized prostate cancer at our institution were included. Five fractions were delivered every other day to the prostate +/- seminal vesicles [clinical target volume (CTV)] with 3 mm/3% robustness. A 4-field arrangement with 2 anterior oblique and 2 opposed lateral beams was used in most patients (97%), and most (99%) had a retroprostatic hydrogel spacer. Results A total of 534 patients with low (14%), favorable intermediate (45%), unfavorable intermediate (36%), high (4.0%), or very high-risk (0.6%) disease are evaluated. Prescription dose was 36.25 Gy (31%), 38 Gy (38%), or 40 Gy (31%) was prescribed. Median volume percentage of CTV receiving at least 100% of prescription dose [V100% (%)] was 100% [interquartile range: 99.99-100]. Rectum V50% (%), V80% (%), and V90% (%) were significantly lower in patients who had spacer, with a mean difference of -9.70%, -6.59%, and -4.42%, respectively, compared to those who did not have spacer. Femoral head dose was lower with a 4-field arrangement. Mean differences in left and right femoral head V40% (%) were -6.99% and -10.74%, respectively. Conclusion We provide a large, novel report of patients treated with IMPT SABR for localized prostate cancer. Four-field IMPT with hydrogel spacer provides significant sparing of rectum and femoral heads without compromising target coverage.
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Affiliation(s)
- Robert W. Gao
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Jiasen Ma
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Thomas M. Pisansky
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Jon J. Kruse
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Bradley J. Stish
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Roman O. Kowalchuk
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Mark R. Waddle
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Ryan M. Phillips
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Richard Choo
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
| | - Brian J. Davis
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
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3
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Holtzman AL, Mohammadi H, Furutani KM, Koffler DM, McGee LA, Lester SC, Gamez ME, Routman DM, Beltran CJ, Liang X. Impact of Relative Biologic Effectiveness for Proton Therapy for Head and Neck and Skull-Base Tumors: A Technical and Clinical Review. Cancers (Basel) 2024; 16:1947. [PMID: 38893068 PMCID: PMC11171304 DOI: 10.3390/cancers16111947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 05/17/2024] [Accepted: 05/18/2024] [Indexed: 06/21/2024] Open
Abstract
Proton therapy has emerged as a crucial tool in the treatment of head and neck and skull-base cancers, offering advantages over photon therapy in terms of decreasing integral dose and reducing acute and late toxicities, such as dysgeusia, feeding tube dependence, xerostomia, secondary malignancies, and neurocognitive dysfunction. Despite its benefits in dose distribution and biological effectiveness, the application of proton therapy is challenged by uncertainties in its relative biological effectiveness (RBE). Overcoming the challenges related to RBE is key to fully realizing proton therapy's potential, which extends beyond its physical dosimetric properties when compared with photon-based therapies. In this paper, we discuss the clinical significance of RBE within treatment volumes and adjacent serial organs at risk in the management of head and neck and skull-base tumors. We review proton RBE uncertainties and its modeling and explore clinical outcomes. Additionally, we highlight technological advancements and innovations in plan optimization and treatment delivery, including linear energy transfer/RBE optimizations and the development of spot-scanning proton arc therapy. These advancements show promise in harnessing the full capabilities of proton therapy from an academic standpoint, further technological innovations and clinical outcome studies, however, are needed for their integration into routine clinical practice.
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Affiliation(s)
- Adam L. Holtzman
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Homan Mohammadi
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Keith M. Furutani
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Daniel M. Koffler
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Lisa A. McGee
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ 85054, USA
| | - Scott C. Lester
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Mauricio E. Gamez
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - David M. Routman
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Chris J. Beltran
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Xiaoying Liang
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL 32224, USA
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4
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Gardner LL, O'Connor JD, McMahon SJ. Benchmarking proton RBE models. Phys Med Biol 2024; 69:085022. [PMID: 38471187 DOI: 10.1088/1361-6560/ad3329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 03/12/2024] [Indexed: 03/14/2024]
Abstract
Objective.To biologically optimise proton therapy, models which can accurately predict variations in proton relative biological effectiveness (RBE) are essential. Current phenomenological models show large disagreements in RBE predictions, due to different model assumptions and differences in the data to which they were fit. In this work, thirteen RBE models were benchmarked against a comprehensive proton RBE dataset to evaluate predictions when all models are fit using the same data and fitting techniques, and to assess the statistical robustness of the models.Approach.Model performance was initially evaluated by fitting to the full dataset, and then a cross-validation approach was applied to assess model generalisability and robustness. The impact of weighting the fit and the choice of biological endpoint (either single or multiple survival levels) was also evaluated.Main results.Fitting the models to a common dataset reduced differences between their predictions, however significant disagreements remained due to different underlying assumptions. All models performed poorly under cross-validation in the weighted fits, suggesting that some uncertainties on the experimental data were significantly underestimated, resulting in over-fitting and poor performance on unseen data. The simplest model, which depends linearly on the LET but has no tissue or dose dependence, performed best for a single survival level. However, when fitting to multiple survival levels simultaneously, more complex models with tissue dependence performed better. All models had significant residual uncertainty in their predictions compared to experimental data.Significance.This analysis highlights that poor quality of error estimation on the dose response parameters introduces substantial uncertainty in model fitting. The significant residual error present in all approaches illustrates the challenges inherent in fitting to large, heterogeneous datasets and the importance of robust statistical validation of RBE models.
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Affiliation(s)
- Lydia L Gardner
- Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom
| | - John D O'Connor
- School of Engineering, Ulster University, Belfast, United Kingdom
| | - Stephen J McMahon
- Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom
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Gao Y, Chang CW, Pan S, Peng J, Ma C, Patel P, Roper J, Zhou J, Yang X. Deep learning-based synthetic dose-weighted LET map generation for intensity modulated proton therapy. Phys Med Biol 2024; 69:025004. [PMID: 38091613 PMCID: PMC10767225 DOI: 10.1088/1361-6560/ad154b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 12/02/2023] [Accepted: 12/13/2023] [Indexed: 01/06/2024]
Abstract
The advantage of proton therapy as compared to photon therapy stems from the Bragg peak effect, which allows protons to deposit most of their energy directly at the tumor while sparing healthy tissue. However, even with such benefits, proton therapy does present certain challenges. The biological effectiveness differences between protons and photons are not fully incorporated into clinical treatment planning processes. In current clinical practice, the relative biological effectiveness (RBE) between protons and photons is set as constant 1.1. Numerous studies have suggested that the RBE of protons can exhibit significant variability. Given these findings, there is a substantial interest in refining proton therapy treatment planning to better account for the variable RBE. Dose-average linear energy transfer (LETd) is a key physical parameter for evaluating the RBE of proton therapy and aids in optimizing proton treatment plans. Calculating precise LETddistributions necessitates the use of intricate physical models and the execution of specialized Monte-Carlo simulation software, which is a computationally intensive and time-consuming progress. In response to these challenges, we propose a deep learning based framework designed to predict the LETddistribution map using the dose distribution map. This approach aims to simplify the process and increase the speed of LETdmap generation in clinical settings. The proposed CycleGAN model has demonstrated superior performance over other GAN-based models. The mean absolute error (MAE), peak signal-to-noise ratio and normalized cross correlation of the LETdmaps generated by the proposed method are 0.096 ± 0.019 keVμm-1, 24.203 ± 2.683 dB, and 0.997 ± 0.002, respectively. The MAE of the proposed method in the clinical target volume, bladder, and rectum are 0.193 ± 0.103, 0.277 ± 0.112, and 0.211 ± 0.086 keVμm-1, respectively. The proposed framework has demonstrated the feasibility of generating synthetic LETdmaps from dose maps and has the potential to improve proton therapy planning by providing accurate LETdinformation.
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Affiliation(s)
- Yuan Gao
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
| | - Chih-Wei Chang
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
| | - Shaoyan Pan
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
- Department of Biomedical Informatics, Emory University, Atlanta, GA, United States of America
| | - Junbo Peng
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
| | - Chaoqiong Ma
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
| | - Pretesh Patel
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
| | - Justin Roper
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
| | - Jun Zhou
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
| | - Xiaofeng Yang
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, United States of America
- Department of Biomedical Informatics, Emory University, Atlanta, GA, United States of America
- Department of Nuclear & Radiological Engineering and Medical Physics, Georgia Institute of Technology, Atlanta, GA, United States of America
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Bianchi A, Selva A, Rossignoli M, Pasquato F, Missiaggia M, La Tessa C, Scifoni E, Tommasino F, Conte V. Microdosimetric analysis of the radiation quality of two different proton beams in the distal edge of the depth-dose profile. RADIATION PROTECTION DOSIMETRY 2023; 199:1979-1983. [PMID: 37819318 DOI: 10.1093/rpd/ncac236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 10/20/2022] [Accepted: 10/21/2022] [Indexed: 10/13/2023]
Abstract
Proton-therapy exploits the advantageous depth-dose profile of protons to induce the highest damage to tumoral cells in the last millimetres of their range in sharp Bragg Peak. To cover the whole tumoral volume, beams of different energies are combined to create the Spread Out Bragg Peak (SOBP). In passive modulated beams, the energy spread is created with modulators in which the highest energy beam is degraded through different thicknesses of calibrated plastic materials. The highest energy is chosen depending on the deepest point that needs to be treated. This study aims to investigate differences in the radiation quality in the distal edge of SOBP beams with different initial energy and modulation techniques based on microdosimetric measurements with mini Tissue-Equivalent Proportional Counters. The beams investigated are the 62 MeV proton SOBP of the clinical facility of CATANA and the 148 MeV proton SOBP of the research beam line of the proton-therapy centre of Trento.
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Affiliation(s)
- A Bianchi
- INFN-Laboratori Nazionali di Legnaro, 35020 Legnaro, Italy
| | - A Selva
- INFN-Laboratori Nazionali di Legnaro, 35020 Legnaro, Italy
| | - M Rossignoli
- INFN-Laboratori Nazionali di Legnaro, 35020 Legnaro, Italy
| | - F Pasquato
- INFN-Laboratori Nazionali di Legnaro, 35020 Legnaro, Italy
| | - M Missiaggia
- University of Trento, Dipartimento di Fisica, 38123 Povo Trento, Italy
- Trento Institute of Fundamental Physics and Applications, 38123 Povo Trento, Italy
| | - C La Tessa
- University of Trento, Dipartimento di Fisica, 38123 Povo Trento, Italy
- Trento Institute of Fundamental Physics and Applications, 38123 Povo Trento, Italy
| | - E Scifoni
- Trento Institute of Fundamental Physics and Applications, 38123 Povo Trento, Italy
| | - F Tommasino
- University of Trento, Dipartimento di Fisica, 38123 Povo Trento, Italy
- Trento Institute of Fundamental Physics and Applications, 38123 Povo Trento, Italy
| | - V Conte
- INFN-Laboratori Nazionali di Legnaro, 35020 Legnaro, Italy
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7
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McIntyre M, Wilson P, Gorayski P, Bezak E. A Systematic Review of LET-Guided Treatment Plan Optimisation in Proton Therapy: Identifying the Current State and Future Needs. Cancers (Basel) 2023; 15:4268. [PMID: 37686544 PMCID: PMC10486456 DOI: 10.3390/cancers15174268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/16/2023] [Accepted: 08/17/2023] [Indexed: 09/10/2023] Open
Abstract
The well-known clinical benefits of proton therapy are achieved through higher target-conformality and normal tissue sparing than conventional radiotherapy. However, there is an increased sensitivity to uncertainties in patient motion/setup, proton range and radiobiological effect. Although recent efforts have mitigated some uncertainties, radiobiological effect remains unresolved due to a lack of clinical data for relevant endpoints. Therefore, RBE optimisations may be currently unsuitable for clinical treatment planning. LET optimisation is a novel method that substitutes RBE with LET, shifting LET hotspots outside critical structures. This review outlines the current status of LET optimisation in proton therapy, highlighting knowledge gaps and possible future research. Following the PRISMA 2020 guidelines, a search of the MEDLINE® and Scopus databases was performed in July 2023, identifying 70 relevant articles. Generally, LET optimisation methods achieved their treatment objectives; however, clinical benefit is patient-dependent. Inconsistencies in the reported data suggest further testing is required to identify therapeutically favourable methods. We discuss the methods which are suitable for near-future clinical deployment, with fast computation times and compatibility with existing treatment protocols. Although there is some clinical evidence of a correlation between high LET and adverse effects, further developments are needed to inform future patient selection protocols for widespread application of LET optimisation in proton therapy.
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Affiliation(s)
- Melissa McIntyre
- Allied Health & Human Performance Academic Unit, University of South Australia, Adelaide, SA 5000, Australia
| | - Puthenparampil Wilson
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, SA 5000, Australia
- UniSA STEM, University of South Australia, Adelaide, SA 5000, Australia
| | - Peter Gorayski
- Allied Health & Human Performance Academic Unit, University of South Australia, Adelaide, SA 5000, Australia
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, SA 5000, Australia
- Australian Bragg Centre for Proton Therapy and Research, Adelaide, SA 5000, Australia
| | - Eva Bezak
- Allied Health & Human Performance Academic Unit, University of South Australia, Adelaide, SA 5000, Australia
- Department of Physics, University of Adelaide, Adelaide, SA 5005, Australia
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8
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DeCunha JM, Newpower M, Mohan R. GPU-accelerated calculation of proton microdosimetric spectra as a function of target size, proton energy, and bounding volume size. Phys Med Biol 2023; 68:165012. [PMID: 37429311 DOI: 10.1088/1361-6560/ace60a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 07/10/2023] [Indexed: 07/12/2023]
Abstract
Objective.Shortcomings of dose-averaged linear energy transfer (LETD), the quantity which is most commonly used to quantify proton relative biological effectiveness, have long been recognized. Microdosimetric spectra may overcome the limitations of LETDbut are extremely computationally demanding to calculate. A systematic library of lineal energy spectra for monoenergetic protons could enable rapid determination of microdosimetric spectra in a clinical environment. The objective of this work was to calculate and validate such a library of lineal energy spectra.Approach. SuperTrack, a GPU-accelerated CUDA/C++ based application, was developed to superimpose tracks calculated using Geant4 onto targets of interest and to compute microdosimetric spectra. Lineal energy spectra of protons with energies from 0.1 to 100 MeV were determined in spherical targets of diameters from 1 nm to 10μm and in bounding voxels with side lengths of 5μm and 3 mm.Main results.Compared to an analogous Geant4-based application, SuperTrack is up to 3500 times more computationally efficient if each track is resampled 1000 times. Dose spectra of lineal energy and dose-mean lineal energy calculated with SuperTrack were consistent with values published in the literature and with comparison to a Geant4 simulation. Using SuperTrack, we developed the largest known library of proton microdosimetric spectra as a function of primary proton energy, target size, and bounding volume size.Significance. SuperTrack greatly increases the computational efficiency of the calculation of microdosimetric spectra. The elevated lineal energy observed in a 3 mm side length bounding volume suggests that lineal energy spectra determined experimentally or computed in small bounding volumes may not be representative of the lineal energy spectra in voxels of a dose calculation grid. The library of lineal energy spectra calculated in this work could be integrated with a treatment planning system for rapid determination of lineal energy spectra in patient geometries.
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Affiliation(s)
- Joseph M DeCunha
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States of America
- Medical Physics Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, United States of America
| | - Mark Newpower
- University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States of America
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States of America
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Missiaggia M, Cartechini G, Tommasino F, Scifoni E, La Tessa C. Investigation of In-Field and Out-of-Field Radiation Quality With Microdosimetry and Its Impact on Relative Biological Effectiveness in Proton Therapy. Int J Radiat Oncol Biol Phys 2023; 115:1269-1282. [PMID: 36442542 DOI: 10.1016/j.ijrobp.2022.11.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 11/09/2022] [Accepted: 11/18/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE Using microdosimetry, this study investigated the relative biological effectiveness (RBE) and quality factor (Q¯) variations in field and out of field as a function of radiation quality for clinical protons. METHODS AND MATERIALS A water phantom with a spread-out Bragg peak (SOBP) was irradiated to acquire microdosimetric spectra at several distal and lateral depths with a tissue equivalent proportional counter. The measurements were used as inputs to microdosimetric kinetic and Loncol models to determine the RBE spatial distribution and compare it with predictions from the dose-averaged linear energy transfer-based McNamara model. Q¯ values and biological and dose equivalent values were also calculated. RESULTS The data demonstrated that radiation quality changed more rapidly with depth than lateral distance from the SOBP. In beam, yD ranged from approximately 4 keV/μm at the entrance to 8 keV/μm at the SOBP far end, reaching approximately 15 keV/μm at the penumbra. Out of field, the overall highest value of 23 ± 2 keV/μm was observed at the beam-edge penumbra. Radiation quality changes caused RBE deviations from the clinical value of 1.1, whose extent depends on the approach used for assessing radiation quality as well as on the radiobiological model. For RBE10, microdosimetry-based models appeared to better reproduce the radiobiological data than the dose-averaged linear energy transfer model. Out of field, both the RBE and Q¯ values appeared to have limitations in describing the radiation biological effectiveness. This research also presents a first comprehensive benchmark of TOPAS code against in-field and out-of-field microdosimetric spectra of therapeutic protons. CONCLUSIONS Further investigation will be necessary to evaluate the quantitative effects of RBE variations on treatment planning and assess the clinical consequences in terms of both tumor control and normal-tissue toxicity. The achievement of this goal calls for accurate radiobiological data to validate the RBE models.
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Affiliation(s)
- Marta Missiaggia
- Department of Physics, University of Trento, Trento, Italy; Trento Institute of Fundamental Physics and Applications (INFN-TIFPA), Trento, Italy; Department of Radiation Oncology, University of Miami, Miami, Florida
| | - Giorgio Cartechini
- Department of Physics, University of Trento, Trento, Italy; Trento Institute of Fundamental Physics and Applications (INFN-TIFPA), Trento, Italy
| | - Francesco Tommasino
- Department of Physics, University of Trento, Trento, Italy; Trento Institute of Fundamental Physics and Applications (INFN-TIFPA), Trento, Italy
| | - Emanuele Scifoni
- Trento Institute of Fundamental Physics and Applications (INFN-TIFPA), Trento, Italy
| | - Chiara La Tessa
- Department of Physics, University of Trento, Trento, Italy; Trento Institute of Fundamental Physics and Applications (INFN-TIFPA), Trento, Italy; Department of Radiation Oncology, University of Miami, Miami, Florida.
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10
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Guan F, Wang X, Yang M, Draeger E, Han D, Iga K, Guo F, Perles L, Li Y, Sahoo N, Mohan R, Chen Z. Dosimetric response of Gafchromic ™ EBT-XD film to therapeutic protons. PRECISION RADIATION ONCOLOGY 2023; 7:15-26. [PMID: 37868341 PMCID: PMC10586355 DOI: 10.1002/pro6.1187] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 01/08/2023] [Indexed: 03/06/2023] Open
Abstract
EBT-XD model of Gafchromic™ films has a broader optimal dynamic dose range, up to 40 Gy, compared to its predecessor models. This characteristic has made EBT-XD films suitable for high-dose applications such as stereotactic body radiotherapy and stereotactic radiosurgery, as well as ultra-high dose rate FLASH radiotherapy. The purpose of the current study was to characterize the dependence of EBT-XD film response on linear energy transfer (LET) and dose rate of therapeutic protons from a synchrotron. A clinical spot-scanning proton beam was used to study LET dependence at three dose-averaged LET (LETd) values of 1.0 keV/µm, 3.6 keV/µm, and 7.6 keV/µm. A research proton beamline was used to study dose rate dependence at 150 Gy/second in the FLASH mode and 0.3 Gy/second in the non-FLASH mode. Film response data from LETd values of 0.9 keV/µm and 9.0 keV/µm of the proton FLASH beam were also compared. Film response data from a clinical 6 MV photon beam were used as a reference. Both gray value method and optical density (OD) method were used in film calibration. Calibration results using a specific OD calculation method and a generic OD calculation method were compared. The four-parameter NIH Rodbard function and three-parameter rational function were compared in fitting the calibration curves. Experimental results showed that the response of EBT-XD film is proton LET dependent but independent of dose rate. Goodness-of-fit analysis showed that using the NIH Rodbard function is superior for both protons and photons. Using the "specific OD + NIH Rodbard function" method for EBT-XD film calibration is recommended.
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Affiliation(s)
- Fada Guan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
- Department of Therapeutic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06510, USA; Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030
| | - Xiaochun Wang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Ming Yang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Emily Draeger
- Department of Therapeutic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06510, USA; Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030
| | - Dae Han
- Department of Therapeutic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06510, USA; Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030
| | - Kiminori Iga
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
- Particle Therapy Division, Hitachi America, Ltd, 2535 Augustine Drive, Santa Clara, California 95054, USA
| | - Fanqing Guo
- Department of Therapeutic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06510, USA; Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030
| | - Luis Perles
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Yuting Li
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Narayan Sahoo
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center,1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Zhe Chen
- Department of Therapeutic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06510, USA; Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030
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11
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Bianchi A, Selva A, Reniers B, Vanhavere F, Conte V. TOPAS simulations of the response of a mini-TEPC: benchmark with experimental data. Phys Med Biol 2023; 68. [PMID: 36595254 DOI: 10.1088/1361-6560/acabfe] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022]
Abstract
Objective. Microdosimetry offers a fast tool for radiation quality (RQ) verification to be implemented in treatment planning systems in proton therapy based on variable LET or RBE to move forward from the use of a fixed RBE of 1.1. It is known that the RBE of protons can increase up to 50% higher than that value in the last few millimetres of their range. Microdosimetry can be performed both experimentally and by means of Monte Carlo (MC) simulations. This paper has the aim of comparing the two approaches.Approach. Experimental measurements have been performed using a miniaturized Tissue equivalent proportional counter developed at the Legnaro National Laboratories of the Italian National Institute for Nuclear Physics with the aim of being used as RQ monitors for high intensity beams. MC simulations have been performed using the microdosimetric extension of TOPAS which provides optimized parameters and scorers for this application.Main results. Simulations were compared with experimental microdosimetric spectra in terms of shape of the spectra and their average values. Moreover, the latter have been investigated as possible estimators of LET obtained with the same MC code. The shape of the spectra is in general consistent with the experimental distributions and the average values of the distributions in both cases can predict the RQ increase with depth.Significance. This study aims at the comparison of microdosimetric spectra obtained from both experimental measurements and the microdosimetric extension of TOPAS in the same radiation field.
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Affiliation(s)
- Anna Bianchi
- INFN Laboratori Nazionali di Legnaro, viale dell'Università 2, I-35020 Legnaro, Italy
| | - Anna Selva
- INFN Laboratori Nazionali di Legnaro, viale dell'Università 2, I-35020 Legnaro, Italy
| | - Brigitte Reniers
- UHasselt, Faculty of Engineering Technology, Centre for Environmental Sciences, Nuclear Technology Center, Agoralaan 3590 Diepenbeek, Belgium
| | - Filip Vanhavere
- Belgian Nuclear Research Centre, SCK CEN, Boeretang 200, 2400 Mol, Belgium
| | - Valeria Conte
- INFN Laboratori Nazionali di Legnaro, viale dell'Università 2, I-35020 Legnaro, Italy
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12
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Chen M, Cao W, Yepes P, Guan F, Poenisch F, Xu C, Chen J, Li Y, Vazquez I, Yang M, Zhu XR, Zhang X. Impact of dose calculation accuracy on inverse linear energy transfer optimization for intensity‐modulated proton therapy. PRECISION RADIATION ONCOLOGY 2022. [DOI: 10.1002/pro6.1179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Mei Chen
- Department of Radiation Oncology Ruijin Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Wenhua Cao
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Pablo Yepes
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
- Physics and Astronomy Department Rice University Houston Texas USA
| | - Fada Guan
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Falk Poenisch
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Cheng Xu
- Department of Radiation Oncology Ruijin Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Jiayi Chen
- Department of Radiation Oncology Ruijin Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Yupeng Li
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Ivan Vazquez
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Ming Yang
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - X. Ronald Zhu
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Xiaodong Zhang
- Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
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13
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McNerlin C, Guan F, Bronk L, Lei K, Grosshans D, Young DW, Gaber MW, Maletic-Savatic M. Targeting hippocampal neurogenesis to protect astronauts' cognition and mood from decline due to space radiation effects. LIFE SCIENCES IN SPACE RESEARCH 2022; 35:170-179. [PMID: 36336363 DOI: 10.1016/j.lssr.2022.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/30/2022] [Accepted: 07/26/2022] [Indexed: 06/16/2023]
Abstract
Neurogenesis is an essential, lifelong process during which neural stem cells generate new neurons within the hippocampus, a center for learning, memory, and mood control. Neural stem cells are vulnerable to environmental insults spanning from chronic stress to radiation. These insults reduce their numbers and diminish neurogenesis, leading to memory decline, anxiety, and depression. Preserving neural stem cells could thus help prevent these neurogenesis-associated pathologies, an outcome particularly important for long-term space missions where environmental exposure to radiation is significantly higher than on Earth. Multiple developments, from mechanistic discoveries of radiation injury on hippocampal neurogenesis to new platforms for the development of selective, specific, effective, and safe small molecules as neurogenesis-protective agents hold great promise to minimize radiation damage on neurogenesis. In this review, we summarize the effects of space-like radiation on hippocampal neurogenesis. We then focus on current advances in drug discovery and development and discuss the nuclear receptor TLX/NR2E1 (oleic acid receptor) as an example of a neurogenic target that might rescue neurogenesis following radiation.
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Affiliation(s)
- Clare McNerlin
- Georgetown University School of Medicine, 3900 Reservoir Rd NW, Washington D.C. 20007, United States of America
| | - Fada Guan
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, 06510, United States of America
| | - Lawrence Bronk
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, United States of America
| | - Kevin Lei
- Graduate School for Biomedical Sciences, Baylor College of Medicine, Houston, Texas, 77030, United States of America; Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America
| | - David Grosshans
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, United States of America
| | - Damian W Young
- Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America; Center for Drug Discovery, Department of Pathology and Immunology Baylor College of Medicine, Houston, Texas, 77030, United States of America; Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas 77030, United States of America
| | - M Waleed Gaber
- Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America.
| | - Mirjana Maletic-Savatic
- Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America; Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America; Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America.
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14
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The Mayo Clinic Florida Microdosimetric Kinetic Model of Clonogenic Survival: Application to Various Repair-Competent Rodent and Human Cell Lines. Int J Mol Sci 2022; 23:ijms232012491. [PMID: 36293348 PMCID: PMC9604502 DOI: 10.3390/ijms232012491] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/04/2022] [Accepted: 10/11/2022] [Indexed: 11/30/2022] Open
Abstract
The relative biological effectiveness (RBE) calculations used during the planning of ion therapy treatments are generally based on the microdosimetric kinetic model (MKM) and the local effect model (LEM). The Mayo Clinic Florida MKM (MCF MKM) was recently developed to overcome the limitations of previous MKMs in reproducing the biological data and to eliminate the need for ion-exposed in vitro data as input for the model calculations. Since we are considering to implement the MCF MKM in clinic, this article presents (a) an extensive benchmark of the MCF MKM predictions against corresponding in vitro clonogenic survival data for 4 rodent and 10 cell lines exposed to ions from 1H to 238U, and (b) a systematic comparison with published results of the latest version of the LEM (LEM IV). Additionally, we introduce a novel approach to derive an approximate value of the MCF MKM model parameters by knowing only the animal species and the mean number of chromosomes. The overall good agreement between MCF MKM predictions and in vitro data suggests the MCF MKM can be reliably used for the RBE calculations. In most cases, a reasonable agreement was found between the MCF MKM and the LEM IV.
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15
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Bianchi A, Selva A, Rossignoli M, Pasquato F, Missiaggia M, Scifoni E, La Tessa C, Tommasino F, Conte V. Microdosimetry with a mini-TEPC in the spread-out Bragg peak of 148 MeV protons. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Faught AM, Wilson LJ, Gargone M, Pirlepesov F, Moskvin VP, Hua C. Treatment-planning approaches to intensity modulated proton therapy and the impact on dose-weighted linear energy transfer. J Appl Clin Med Phys 2022; 24:e13782. [PMID: 36161765 PMCID: PMC9859995 DOI: 10.1002/acm2.13782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 07/13/2022] [Accepted: 08/16/2022] [Indexed: 01/26/2023] Open
Abstract
PURPOSE We quantified the effect of various forward-based treatment-planning strategies in proton therapy on dose-weighted linear energy transfer (LETd). By maintaining the dosimetric quality at a clinically acceptable level, we aimed to evaluate the differences in LETd among various treatment-planning approaches and their practicality in minimizing biologic uncertainties associated with LETd. METHOD Eight treatment-planning strategies that are achievable in commercial treatment-planning systems were applied on a cylindrical water phantom and four pediatric brain tumor cases. Each planning strategy was compared to either an opposed lateral plan (phantom study) or original clinical plan (patient study). Deviations in mean and maximum LETd from clinically acceptable dose distributions were compared. RESULTS In the phantom study, using a range shifter and altering the robust scenarios during optimization had the largest effect on the mean clinical target volume LETd, which was reduced from 4.5 to 3.9 keV/μm in both cases. Variations in the intersection angle between beams had the largest effect on LETd in a ring defined 3 to 5 mm outside the target. When beam intersection angles were reduced from opposed laterals (180°) to 120°, 90°, and 60°, corresponding maximum LETd increased from 7.9 to 8.9, 10.9, and 12.2 keV/μm, respectively. A clear trend in mean and maximum LETd variations in the clinical cases could not be established, though spatial distribution of LETd suggested a strong dependence on patient anatomy and treatment geometry. CONCLUSION Changes in LETd from treatment-plan setup follow intuitive trends in a controlled phantom experiment. Anatomical and other patient-specific considerations, however, can preclude generalizable strategies in clinical cases. For pediatric cranial radiation therapy, we recommend using opposed lateral treatment fields to treat midline targets.
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Affiliation(s)
- Austin M. Faught
- Department of Radiation OncologySt. Jude Children's Research HospitalMemphisTennesseeUSA
| | - Lydia J. Wilson
- Department of Radiation OncologySt. Jude Children's Research HospitalMemphisTennesseeUSA
| | - Melissa Gargone
- Department of Radiation OncologySt. Jude Children's Research HospitalMemphisTennesseeUSA
| | - Fakhriddin Pirlepesov
- Department of Radiation OncologySt. Jude Children's Research HospitalMemphisTennesseeUSA
| | - Vadim P. Moskvin
- Department of Radiation OncologySt. Jude Children's Research HospitalMemphisTennesseeUSA
| | - Chia‐Ho Hua
- Department of Radiation OncologySt. Jude Children's Research HospitalMemphisTennesseeUSA
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17
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Yang M, Wang X, Guan F, Titt U, Iga K, Jiang D, Takaoka T, Tootake S, Katayose T, Umezawa M, Schüler E, Frank S, Lin SH, Sahoo N, Koong AC, Mohan R, Zhu XR. Adaptation and dosimetric commissioning of a synchrotron-based proton beamline for FLASH experiments. Phys Med Biol 2022; 67. [PMID: 35853442 PMCID: PMC9422888 DOI: 10.1088/1361-6560/ac8269] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 07/19/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Objective. Irradiation with ultra-high dose rates (>40 Gy s−1), also known as FLASH irradiation, has the potential to shift the paradigm of radiation therapy because of its reduced toxicity to normal tissues compared to that of conventional irradiations. The goal of this study was to (1) achieve FLASH irradiation conditions suitable for pre-clinical i
n vitro and in vivo biology experiments using our synchrotron-based proton beamline and (2) commission the FLASH irradiation conditions achieved. Approach. To achieve these suitable FLASH conditions, we made a series of adaptations to our proton beamline, including modifying the spill length and size of accelerating cycles, repurposing the reference monitor for dose control, and expanding the field size with a custom double-scattering system. We performed the dosimetric commissioning with measurements using an Advanced Markus chamber and EBT-XD films as well as with Monte Carlo simulations. Main results. Through adaptations, we have successfully achieved FLASH irradiation conditions, with an average dose rate of up to 375 Gy s−1. The Advanced Markus chamber was shown to be appropriate for absolute dose calibration under our FLASH conditions with a recombination factor ranging from 1.002 to 1.006 because of the continuous nature of our synchrotron-based proton delivery within a spill. Additionally, the absolute dose measured using the Advanced Markus chamber and EBT-XD films agreed well, with average and maximum differences of 0.32% and 1.63%, respectively. We also performed a comprehensive temporal analysis for FLASH spills produced by our system, which helped us identify a unique relationship between the average dose rate and the dose in our FLASH irradiation. Significance. We have established a synchrotron-based proton FLASH irradiation platform with accurate and precise dosimetry that is suitable for pre-clinical biology experiments. The unique time structure of the FLASH irradiation produced by our synchrotron-based system may shed new light onto the mechanism behind the FLASH effect.
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18
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MD JKB, Amer A, Khose S, Flint D, Adair A, Yepes P, Grosshans D, Johnson J, Chung C. Brain Radionecrosis Outside the Target Volume after Proton Radiotherapy: Analyses of Multiparametric Imaging and Proton Biological Effectiveness. Adv Radiat Oncol 2022; 7:101044. [DOI: 10.1016/j.adro.2022.101044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 07/27/2022] [Indexed: 11/17/2022] Open
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19
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Interdisciplinary Methods for Zoonotic Tissue Acellularization for Natural Heart Valve Substitute of Biomimetic Materials. MATERIALS 2022; 15:ma15072594. [PMID: 35407927 PMCID: PMC9000896 DOI: 10.3390/ma15072594] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/14/2022] [Accepted: 03/29/2022] [Indexed: 02/04/2023]
Abstract
The goal of this work was to create a bioactive tissue-based scaffold using multi-disciplinary engineering materials and tissue engineering techniques. Materials & methods: Physical techniques such as direct laser interference lithography and proton radiation were selected as alternative methods of enzymatic and chemical decellularization to remove cells from a tissue without degradation of the extracellular matrix nor its protein structure. This study was an attempt to prepare a functional scaffold for cell culture from tissue of animal origin using new physical methods that have not been considered before. The work was carried out under full control of the histological and molecular analysis. Results & conclusions: The most important finding was that the physical methods used to obtain the decellularized tissue scaffold differed in the efficiency of cell removal from the tissue in favour of the laser method. Both the laser method and the proton method exhibited a destructive effect on tissue structure and the genetic material in cell nuclei. This effect was visible on histology images as blurred areas within the cell nucleus. The finite element 3D simulation of decellularization process of the three-layer tissue of animal origin sample reflected well the mechanical response of tissue described by hyperelastic material models and provided results comparable to the experimental ones.
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20
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Poon DMC, Wu S, Ho L, Cheung KY, Yu B. Proton Therapy for Prostate Cancer: Challenges and Opportunities. Cancers (Basel) 2022; 14:cancers14040925. [PMID: 35205673 PMCID: PMC8870339 DOI: 10.3390/cancers14040925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 01/02/2023] Open
Abstract
Simple Summary Reported clinical outcomes of proton therapy (PT) for localized prostate cancer are similar to photon-based external beam radiotherapy. Apparently, the dosimetric advantages of PT have yet to be translated to clinical benefits. The suboptimal clinical outcomes of PT might be attributable to inadequate dose prescription, as indicated by the ASCENDE-RT trial. Moreover, uncertainties involved in the treatment planning and delivery processes, as well as technological limitations in PT treatment systems, may lead to discrepancies between planned doses and actual doses delivered to patients. In this article, we reviewed the current status of PT for prostate cancer and discussed different clinical implementations that could potentially improve the clinical outcome of PT for prostate cancer. Various technological advancements under which uncertainties in dose calculations can be minimized, including MRI-guided PT, dual-energy photon-counting CT and high-resolution Monte Carlo-based treatment planning systems, are highlighted. Abstract The dosimetric advantages of proton therapy (PT) treatment plans are demonstrably superior to photon-based external beam radiotherapy (EBRT) for localized prostate cancer, but the reported clinical outcomes are similar. This may be due to inadequate dose prescription, especially in high-risk disease, as indicated by the ASCENDE-RT trial. Alternatively, the lack of clinical benefits with PT may be attributable to improper dose delivery, mainly due to geometric and dosimetric uncertainties during treatment planning, as well as delivery procedures that compromise the dose conformity of treatments. Advanced high-precision PT technologies, and treatment planning and beam delivery techniques are being developed to address these uncertainties. For instance, external magnetic resonance imaging (MRI)-guided patient setup rooms are being developed to improve the accuracy of patient positioning for treatment. In-room MRI-guided patient positioning systems are also being investigated to improve the geometric accuracy of PT. Soon, high-dose rate beam delivery systems will shorten beam delivery time to within one breath hold, minimizing the effects of organ motion and patient movements. Dual-energy photon-counting computed tomography and high-resolution Monte Carlo-based treatment planning systems are available to minimize uncertainties in dose planning calculations. Advanced in-room treatment verification tools such as prompt gamma detector systems will be used to verify the depth of PT. Clinical implementation of these new technologies is expected to improve the accuracy and dose conformity of PT in the treatment of localized prostate cancers, and lead to better clinical outcomes. Improvement in dose conformity may also facilitate dose escalation, improving local control and implementation of hypofractionation treatment schemes to improve patient throughput and make PT more cost effective.
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Affiliation(s)
- Darren M. C. Poon
- Comprehensive Oncology Centre, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China;
| | - Stephen Wu
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
- Correspondence: ; Tel.: +852-29171413
| | - Leon Ho
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
| | - Kin Yin Cheung
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
| | - Ben Yu
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
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Rucinski A, Biernacka A, Schulte R. Applications of nanodosimetry in particle therapy planning and beyond. Phys Med Biol 2021; 66. [PMID: 34731854 DOI: 10.1088/1361-6560/ac35f1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 11/03/2021] [Indexed: 12/28/2022]
Abstract
This topical review summarizes underlying concepts of nanodosimetry. It describes the development and current status of nanodosimetric detector technology. It also gives an overview of Monte Carlo track structure simulations that can provide nanodosimetric parameters for treatment planning of proton and ion therapy. Classical and modern radiobiological assays that can be used to demonstrate the relationship between the frequency and complexity of DNA lesion clusters and nanodosimetric parameters are reviewed. At the end of the review, existing approaches of treatment planning based on relative biological effectiveness (RBE) models or dose-averaged linear energy transfer are contrasted with an RBE-independent approach based on nandosimetric parameters. Beyond treatment planning, nanodosimetry is also expected to have applications and give new insights into radiation protection dosimetry.
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Affiliation(s)
| | - Anna Biernacka
- University of Gdansk, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdansk, 80-307 Gdansk, Poland
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Parisi A, Struelens L, Vanhavere F. Comparison between the results of a recently-developed biological weighting function (V79-RBE 10BWF) and the in vitroclonogenic survival RBE 10of other repair-competent asynchronized normoxic mammalian cell lines and ions not used for the development of the model. Phys Med Biol 2021; 66. [PMID: 34710862 DOI: 10.1088/1361-6560/ac344e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 10/28/2021] [Indexed: 11/11/2022]
Abstract
728 simulated microdosimetric lineal energy spectra (26 different ions between 1H and 238U, 28 energy points from 1 to 1000 MeV/n) were used in combination with a recently-developed biological weighting function (Parisi et al., 2020) and 571 published in vitro clonogenic survival curves in order to: 1) assess prediction intervals for the in silico results by deriving an empirical indication of the experimental uncertainty from the dispersion in the in vitro hamster lung fibroblast (V79) data used for the development of the biophysical model; 2) explore the possibility of modeling the relative biological effectiveness (RBE) of the 10% clonogenic survival of asynchronized normoxic repair-competent mammalian cell lines other than the one used for the development of the model (V79); 3) investigate the predictive power of the model through a comparison between in silico results and in vitro data for 10 ions not used for the development of the model. At first, different strategies for the assessment of the in silico prediction intervals were compared. The possible sources of uncertainty responsible for the dispersion in the in vitro data were also shortly reviewed. Secondly, also because of the relevant scatter in the in vitro data, no statistically-relevant differences were found between the RBE10 of the investigated different asynchronized normoxic repair-competent mammalian cell lines. The only exception (Chinese Hamster peritoneal fibroblasts, B14FAF28), is likely due to the limited dataset (all in vitro ion data were extracted from a single publication), systematic differences in the linear energy transfer (LET) calculations for the employed very-heavy ions, and the use of reference photon survival curves extracted from a different publication. Finally, the in silico predictions for the 10 ions not used for the model development were in good agreement with the corresponding in vitro data.
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Affiliation(s)
- Alessio Parisi
- Radiation Protection Dosimetry and Calibration, Studiecentrum voor Kernenergie, Boeretang 200, Mol, Belgiun, Mol, 2400, BELGIUM
| | - Lara Struelens
- Radiation Protection, Dosimetry and Calibration, Belgian Nuclear Research Centre SCK.CEN, Boeretang 200, Mol, 2400, BELGIUM
| | - Filip Vanhavere
- Institute of Advanced Nuclear Systems, Belgian Nuclear Research Centre SCK.CEN, Boeretang 200, B-2400 Mol, Mol, BELGIUM
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23
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Almhagen E, Traneus E, Ahnesjö A. Handling of beam spectra in training and application of proton RBE models. Phys Med Biol 2021; 66. [PMID: 34464939 DOI: 10.1088/1361-6560/ac226a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 08/31/2021] [Indexed: 11/11/2022]
Abstract
Published data from cell survival experiments are frequently used as training data for models of proton relative biological effectiveness (RBE). The publications rarely provide full information about the primary particle spectrum of the used beam, or its content of heavy secondary particles. The purpose of this paper is to assess to what extent heavy secondary particles may have been present in published cell survival experiments, and to investigate the impact of non-primary protons for RBE calculations in treatment planning. We used the Monte Carlo code Geant4 to calculate the occurrence of non-primary protons and heavier secondary particles for clinical protons beams in water for four incident energies in the [100, 250] MeV interval. We used the resulting spectra together with a conservative RBE parameterization and an RBE model to map both the rise of RBE at the beam entry surface due to heavy secondary particle buildup, and the difference in estimated RBE if non-primary protons are included or not in the beam quality metric. If included, non-primary protons cause a difference of 2% of the RBE in the plateau region of an spread out Bragg peak and 1% in the Bragg peak. Including non-primary protons specifically for RBE calculations will consequently have a negligible impact and can be ignored. A buildup distance in water of one millimeter was sufficient to reach an equilibrium state of RBE for the four incident energies selected. For the investigated experimental data, 83 out of the 86 data points were found to have been determined with at least that amount of buildup material. Hence, RBE model training data should be interpreted to include the contribution of heavy secondaries.
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Affiliation(s)
- Erik Almhagen
- Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Akademiska Sjukhuset, Uppsala, Sweden.,The Skandion Clinic, Uppsala, Sweden
| | | | - Anders Ahnesjö
- Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Akademiska Sjukhuset, Uppsala, Sweden
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Suckert T, Nexhipi S, Dietrich A, Koch R, Kunz-Schughart LA, Bahn E, Beyreuther E. Models for Translational Proton Radiobiology-From Bench to Bedside and Back. Cancers (Basel) 2021; 13:4216. [PMID: 34439370 PMCID: PMC8395028 DOI: 10.3390/cancers13164216] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/09/2021] [Accepted: 08/17/2021] [Indexed: 12/25/2022] Open
Abstract
The number of proton therapy centers worldwide are increasing steadily, with more than two million cancer patients treated so far. Despite this development, pending questions on proton radiobiology still call for basic and translational preclinical research. Open issues are the on-going discussion on an energy-dependent varying proton RBE (relative biological effectiveness), a better characterization of normal tissue side effects and combination treatments with drugs originally developed for photon therapy. At the same time, novel possibilities arise, such as radioimmunotherapy, and new proton therapy schemata, such as FLASH irradiation and proton mini-beams. The study of those aspects demands for radiobiological models at different stages along the translational chain, allowing the investigation of mechanisms from the molecular level to whole organisms. Focusing on the challenges and specifics of proton research, this review summarizes the different available models, ranging from in vitro systems to animal studies of increasing complexity as well as complementing in silico approaches.
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Affiliation(s)
- Theresa Suckert
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, 01309 Dresden, Germany; (T.S.); (S.N.); (A.D.); (L.A.K.-S.)
- German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Sindi Nexhipi
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, 01309 Dresden, Germany; (T.S.); (S.N.); (A.D.); (L.A.K.-S.)
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, 01309 Dresden, Germany
| | - Antje Dietrich
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, 01309 Dresden, Germany; (T.S.); (S.N.); (A.D.); (L.A.K.-S.)
- German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Robin Koch
- Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany; (R.K.); (E.B.)
- Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany
- National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany
| | - Leoni A. Kunz-Schughart
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, 01309 Dresden, Germany; (T.S.); (S.N.); (A.D.); (L.A.K.-S.)
- National Center for Tumor Diseases (NCT), Partner Site Dresden, 01307 Dresden, Germany
| | - Emanuel Bahn
- Heidelberg Institute of Radiation Oncology (HIRO), 69120 Heidelberg, Germany; (R.K.); (E.B.)
- Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany
- National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany
- German Cancer Research Center (DKFZ), Clinical Cooperation Unit Radiation Oncology, 69120 Heidelberg, Germany
| | - Elke Beyreuther
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, 01309 Dresden, Germany; (T.S.); (S.N.); (A.D.); (L.A.K.-S.)
- Helmholtz-Zentrum Dresden—Rossendorf, Institute of Radiation Physics, 01328 Dresden, Germany
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25
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Yang Y, Vargas CE, Bhangoo RS, Wong WW, Schild SE, Daniels TB, Keole SR, Rwigema JCM, Glass JL, Shen J, DeWees TA, Liu T, Bues M, Fatyga M, Liu W. Exploratory Investigation of Dose-Linear Energy Transfer (LET) Volume Histogram (DLVH) for Adverse Events Study in Intensity Modulated Proton Therapy (IMPT). Int J Radiat Oncol Biol Phys 2021; 110:1189-1199. [PMID: 33621660 DOI: 10.1016/j.ijrobp.2021.02.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 01/25/2021] [Accepted: 02/11/2021] [Indexed: 02/06/2023]
Abstract
PURPOSE We proposed a novel tool-a dose linear energy transfer (LET)-volume histogram (DLVH)-and performed an exploratory study to investigate rectal bleeding in prostate cancer treated with intensity modulated proton therapy. METHODS AND MATERIALS The DLVH was constructed with dose and LET as 2 axes, and the normalized volume of the structure was contoured in the dose-LET plane as isovolume lines. We defined the DLVH index, DLv%(d,l) (ie, v% of the structure) to have a dose of ≥d Gy and an LET of ≥l keV/μm, similar to the dose-volume histogram index Dv%. Nine patients with prostate cancer with rectal bleeding (Common Terminology Criteria for Adverse Events grade ≥2) were included as the adverse event group, and 48 patients with no complications were considered the control group. A P value map was constructed by comparison of the DLVH indices of all patients between the 2 groups using the Mann-Whitney U test. Dose-LET volume constraints (DLVCs) were derived based on the P value map with a manual selection procedure facilitated by Spearman's correlation tests. The obtained DLVCs were further cross-validated using a multivariate support vector machine (SVM)-based normal tissue complication probability (NTCP) model with an independent testing data set composed of 8 adverse event and 13 control patients. RESULTS We extracted 2 DLVC constraints. One DLVC was obtained, Vdose/LETboundary:2.5keVμmat 75 Gy to 3.2keVμmat8.65Gy <1.27% (DLVC1), revealing a high LET volume effect. The second DLVC, V(72.2Gy,0keVμm) < 2.23% (DVLC2), revealed a high dose volume effect. The SVM-based NTCP model with 2 DLVCs provided slightly superior performance than using dose only, with an area under the curve of 0.798 versus 0.779 for the testing data set. CONCLUSIONS Our results demonstrated the importance of rectal "hot spots" in both high LET (DLVC1) and high dose (DLVC2) in inducing rectal bleeding. The SVM-based NTCP model confirmed the derived DLVCs as good predictors for rectal bleeding when intensity modulated proton therapy is used to treat prostate cancer.
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Affiliation(s)
- Yunze Yang
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Carlos E Vargas
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Ronik S Bhangoo
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - William W Wong
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Steven E Schild
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Thomas B Daniels
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Sameer R Keole
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | | | - Jennifer L Glass
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Jiajian Shen
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Todd A DeWees
- Division of Biostatics, Mayo Clinic Arizona, Phoenix, Arizona
| | - Tianming Liu
- Department of Computer Science, the University of Georgia, Athens, Georgia
| | - Martin Bues
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Mirek Fatyga
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona
| | - Wei Liu
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona.
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26
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Li X, Ding X, Zheng W, Liu G, Janssens G, Souris K, Barragán-Montero AM, Yan D, Stevens C, Kabolizadeh P. Linear Energy Transfer Incorporated Spot-Scanning Proton Arc Therapy Optimization: A Feasibility Study. Front Oncol 2021; 11:698537. [PMID: 34327139 PMCID: PMC8313436 DOI: 10.3389/fonc.2021.698537] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/22/2021] [Indexed: 02/02/2023] Open
Abstract
Purpose To integrate dose-averaged linear energy transfer (LETd) into spot-scanning proton arc therapy (SPArc) optimization and to explore its feasibility and potential clinical benefits. Methods An open-source proton planning platform (OpenREGGUI) has been modified to incorporate LETd into optimization for both SPArc and multi-beam intensity-modulated proton therapy (IMPT) treatment planning. SPArc and multi-beam IMPT plans with different beam configurations for a prostate patient were generated to investigate the feasibility of LETd-based optimization using SPArc in terms of spatial LETd distribution and plan delivery efficiency. One liver and one brain case were studied to further evaluate the advantages of SPArc over multi-beam IMPT. Results With similar dose distributions, the efficacy of spatially optimizing LETd distributions improves with increasing number of beams. Compared with multi-beam IMPT plans, SPArc plans show substantial improvement in LETd distributions while maintaining similar delivery efficiency. Specifically, for the liver case, the average LETd in the GTV was increased by 124% for the SPArc plan, and only 9.6% for the 2-beam IMPT plan compared with the 2-beam non-LETd optimized IMPT plan. In case of LET optimization for the brain case, the SPArc plan could effectively increase the average LETd in the CTV and decrease the values in the critical structures while smaller improvement was observed in 3-beam IMPT plans. Conclusion This work demonstrates the feasibility and significant advantages of using SPArc for LETd-based optimization, which could maximize the LETd distribution wherever is desired inside the target and averts the high LETd away from the adjacent critical organs-at-risk.
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Affiliation(s)
- Xiaoqiang Li
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, United States
| | - Xuanfeng Ding
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, United States
| | - Weili Zheng
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, United States
| | - Gang Liu
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, United States.,Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Guillaume Janssens
- Advanced Technology Group, Ion Beam Applications SA, Louvain-la-Neuve, Belgium
| | - Kevin Souris
- Center for Molecular Imaging and Experimental Radiotherapy, Institut de Recherche Expérimentale et Clinique, UCLouvain, Brussels, Belgium
| | - Ana M Barragán-Montero
- Center for Molecular Imaging and Experimental Radiotherapy, Institut de Recherche Expérimentale et Clinique, UCLouvain, Brussels, Belgium
| | - Di Yan
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, United States
| | - Craig Stevens
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, United States
| | - Peyman Kabolizadeh
- Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, United States
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27
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Horendeck D, Walsh KD, Hirakawa H, Fujimori A, Kitamura H, Kato TA. High LET-Like Radiation Tracks at the Distal Side of Accelerated Proton Bragg Peak. Front Oncol 2021; 11:690042. [PMID: 34178687 PMCID: PMC8222778 DOI: 10.3389/fonc.2021.690042] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/10/2021] [Indexed: 12/29/2022] Open
Abstract
Proton therapy is a type of hadron radiotherapy used for treating solid tumors. Unlike heavy charged elements, proton radiation is considered to be low LET (Linear Energy Transfer) radiation, like X-rays. However, the clinical SOBP (Spread Out Bragg Peak) proton radiation is considered to be higher in relative biological effectiveness (RBE) than both X-ray and their own entrance region. The RBE is estimated to be 1.1–1.2, which can be attributed to the higher LET at the SOBP region than at the entrance region. In order to clarify the nature of higher LET near the Bragg peak of proton radiation and its potential cytotoxic effects, we utilized a horizontal irradiation system with CHO cells. Additionally, we examined DNA repair mutants, analyzed cytotoxicity with colony formation, and assessed DNA damage and its repair with γ-H2AX foci assay in a high-resolution microscopic scale analysis along with the Bragg peak. Besides confirming that the most cytotoxic effects occurred at the Bragg peak, extended cytotoxicity was observed a few millimeters after the Bragg peak. γ-H2AX foci numbers reached a maximum at the Bragg peak and reduced dramatically after the Bragg peak. However, in the post-Bragg peak region, particle track-like structures were sporadically observed. This region contains foci that are more difficult to repair. The peak and post-Bragg peak regions contain rare high LET-like radiation tracks and can cause cellular lethality. This may have caused unwanted side effects and complexities of outputs for the proton therapy treatment.
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Affiliation(s)
- Dakota Horendeck
- Department of Environmental & Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Kade D Walsh
- Department of Environmental & Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Hirokazu Hirakawa
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Akira Fujimori
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Hisashi Kitamura
- Radiation Emergency Medical Assistance Team, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Takamitsu A Kato
- Department of Environmental & Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
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28
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Bryant CM, Henderson RH, Nichols RC, Mendenhall WM, Hoppe BS, Vargas CE, Daniels TB, Choo CR, Parikh RR, Giap H, Slater JD, Vapiwala N, Barrett W, Nanda A, Mishra MV, Choi S, Liao JJ, Mendenhall NP. Consensus Statement on Proton Therapy for Prostate Cancer. Int J Part Ther 2021; 8:1-16. [PMID: 34722807 PMCID: PMC8489490 DOI: 10.14338/ijpt-20-00031.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 02/02/2021] [Indexed: 11/21/2022] Open
Abstract
Proton therapy is a promising but controversial treatment in the management of prostate cancer. Despite its dosimetric advantages when compared with photon radiation therapy, its increased cost to patients and insurers has raised questions regarding its value. Multiple prospective and retrospective studies have been published documenting the efficacy and safety of proton therapy for patients with localized prostate cancer and for patients requiring adjuvant or salvage pelvic radiation after surgery. The Particle Therapy Co-Operative Group (PTCOG) Genitourinary Subcommittee intends to address current proton therapy indications, advantages, disadvantages, and cost effectiveness. We will also discuss the current landscape of clinical trials. This consensus report can be used to guide clinical practice and research directions.
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Affiliation(s)
- Curtis M. Bryant
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Randal H. Henderson
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA
| | - R. Charles Nichols
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA
| | - William M. Mendenhall
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Bradford S. Hoppe
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, USA
| | | | | | - C. Richard Choo
- Department of Radiation Oncology, Mayo Clinic Rochester, Rochester, MN, USA
| | - Rahul R. Parikh
- Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Huan Giap
- Department of Radiation Oncology, University of Miami Sylvester Comprehensive Cancer Center, Miami, FL, USA
| | - Jerry D. Slater
- Department of Radiation Oncology, Loma Linda University, Loma Linda, CA, USA
| | - Neha Vapiwala
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - William Barrett
- Department of Radiation Oncology, University of Cincinnati, Cincinnati, OH, USA
| | - Akash Nanda
- Department of Radiation Oncology, Orlando Health, Orlando, FL, USA
| | - Mark V. Mishra
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Seungtaek Choi
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, USA
| | - Jay J. Liao
- Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA, USA
| | - Nancy P. Mendenhall
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA
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29
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Distinct imaging patterns of pseudoprogression in glioma patients following proton versus photon radiation therapy. J Neurooncol 2021; 152:583-590. [PMID: 33751335 DOI: 10.1007/s11060-021-03734-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 03/05/2021] [Indexed: 01/07/2023]
Abstract
PURPOSE Criteria by the Radiologic Assessment in Neuro-Oncology (RANO) group outline the diagnosis of pseudoprogression (Ps) after photon therapy for gliomas based on timing and location. We noted that patients receiving proton therapy manifested radiographic changes that appear different than Ps after photon therapy, which could be interpreted as tumor progression. In this study, we retrospectively reviewed MR imaging after proton or photon radiation for gliomas. We propose criteria to characterize proton pseudoprogression (ProPs) as distinct from Ps seen after photons. METHODS Post-treatment MR imaging, clinical and pathological data of low grade glioma patients were reviewed. Overall, 57 patients receiving protons were reviewed for the presence of ProPs, and 43 patients receiving photons were reviewed for any equivalent imaging changes. Data collected included the location and timing of the new enhancement, tumor grade, molecular subtype, chemotherapy received, and clinical symptoms. RESULTS Fourteen patients (24.6%) had new enhancement following radiation therapy that was unique to treatment with protons. The mean time to development of the ProPs was 15.4 months (7-27 months). We established the following criteria to characterize ProPs: located at the distal end of the proton beam; resolves without tumor-directed therapy; and subjectively multifocal, patchy, and small (< 1 cm). In the group receiving photons, none had changes that met our criteria for ProPs. CONCLUSION Patients who receive protons have unique imaging changes after radiation therapy. ProPs could be mistaken for tumor progression, but typically resolves on follow up. Further studies are needed to understand the radiobiology and pathophysiology underlying these imaging changes.
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30
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Nomura K, Iwata H, Toshito T, Omachi C, Nagayoshi J, Nakajima K, Ogino H, Shibamoto Y. Biological effects of passive scattering and spot scanning proton beams at the distal end of the spread-out Bragg peak in single cells and multicell spheroids. Int J Radiat Biol 2021; 97:695-703. [PMID: 33617430 DOI: 10.1080/09553002.2021.1889704] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
PURPOSE The present study investigated the biological effects of spot scanning and passive scattering proton therapies at the distal end region of the spread-out Bragg peak (SOBP) using single cell and multicell spheroids. MATERIALS AND METHODS The Geant4 Monte Carlo simulation was used to calculate linear energy transfer (LET) values in passive scattering and spot scanning beams. The biological doses of the two beam options at various points of the distal end region of SOBP were investigated using EMT6 single cells and 0.6-mm V79 spheroids irradiated with 6 and 15 Gy, respectively, by inserting the fractions surviving these doses onto dose-survival curves and reading the corresponding dose. RESULTS LET values in the entrance region of SOBP were similar between the two beam options and increased at the distal end region of SOBP, where the LET value of spot scanning beams was higher than that of passive scattering beams. Increases in biological effects at the distal end region were similarly observed in single cells and spheroids; biological doses at 2-10 mm behind the distal end were 4.5-57% and 5.7-86% higher than physical doses in passive scattering and spot scanning beams, respectively, with the biological doses of spot scanning beams being higher than those of passive scattering beams (p < .05). CONCLUSIONS In single cells and spheroids, the effects of proton irradiation were stronger than expected from measured physical doses at the distal end of SOBP and were correlated with LET increases.
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Affiliation(s)
- Kento Nomura
- Department of Radiation Oncology, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Nagoya, Japan.,Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Hiromitsu Iwata
- Department of Radiation Oncology, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Nagoya, Japan.,Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Toshiyuki Toshito
- Department of Proton Therapy Physics, Nagoya Proton Therapy Center, Nagoya, Japan
| | - Chihiro Omachi
- Department of Proton Therapy Physics, Nagoya Proton Therapy Center, Nagoya, Japan
| | - Junpei Nagayoshi
- Department of Radiation Therapy, Nagoya City West Medical Center, Nagoya, Japan
| | - Koichiro Nakajima
- Department of Radiation Oncology, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Nagoya, Japan.,Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Hiroyuki Ogino
- Department of Radiation Oncology, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Nagoya, Japan.,Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yuta Shibamoto
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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Shang H, Pu Y, Chen Z, Wang X, Yuan C, Jin X, Liu C. Impact of Multiple Beams on Plan Quality, Linear Energy Transfer Distribution, and Plan Robustness of Intensity Modulated Proton Therapy for Lung Cancer. ACS Sens 2021; 6:408-417. [PMID: 33125211 DOI: 10.1021/acssensors.0c01879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The increase of proton beam number might provide higher degrees of freedom in the optimization of intensity-modulated proton therapy planning. In this study, we aimed to quantitatively explore the potential benefits of the increased beam number, including dose volume histogram (DVH), linear energy transfer volume histogram, and DVH bandwidth metrics. Twelve patients with lung cancer are retrospectively selected. Four plans were created based on internal target volume (ITV) robust optimization for each patient using the RayStation treatment planning system. Four plans were generated using different numbers (three, five, seven, and nine) of evenly separated coplanar beams. The three-beam plan was considered as the reference plan. Biologically equivalent doses were calculated using both constant relative biological effectiveness (RBE) and variable RBE models, respectively. To evaluate plan quality, DVH metrics in the target [ITV: D2%, CI, HI] and organs-at-risk [Lung: V5Gy[RBE], V20Gy[RBE], V30Gy[RBE]; Heart D2%; Spinal cord D2%] were calculated using both RBE models. To evaluate LET distributions, LET volume histogram metrics [ITV LETmean and LET2%; Lung LETmean and LET2%; Heart LET2%; Spinal cord LET2%] were quantified. To evaluate plan robustness, the metrics using DVH bandwidth [ITV: D2%, D99%; Lung: V5Gy[RBE], V20Gy[RBE], V30Gy[RBE]; Heart D2%; Spinal cord D2%] were also reported. For plan quality, the increase of proton beam number resulted in fewer target hot spots, improved target dose conformity, improved target dose homogeneity, lower median-dose lung volume, and fewer hot spots in spinal cord. As to LET distributions, target mean LET increased significantly as the beam number increased to seven or more. Lung LET hot spots were significantly reduced with the increase of proton beams. With respect to plan robustness, the robustness of target dose coverage, target hot spots, and low-dose lung volume were improved, while the robustness of heart hot spots became worse as the beam number increased to nine. The robustness of cord hot spots became worse using five and seven beams compared to that using three beams. As the proton beam number increased, plan quality and LET distributions were comparable or significantly improved. The robustness of target dose coverage, target dose hot spots, and low-dose lung volume were significantly improved.
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Affiliation(s)
- Haijiao Shang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, P. R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- RaySearch China, Shanghai, 200120, P. R. China
| | - Yuehu Pu
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, P. R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Zhiling Chen
- Shanghai Advanced Research Institute, Chinese Academy Sciences, Shanghai, 201210, P. R. China
| | - Xuetao Wang
- Department of Radiation Oncology, West China Hospital, Sichuan University, Chengdu, 610041, P. R. China
| | - Cuiyun Yuan
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, 518116, P. R. China
| | - Xiance Jin
- Department of Radiation and Medical Oncology, The 1st Affiliated Hospital of Wenzhou Medical University, Wenzhou, 32500, P. R. China
| | - Chenbin Liu
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, 518116, P. R. China
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32
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Conte V, Agosteo S, Bianchi A, Bolst D, Bortot D, Catalano R, Cirrone GAP, Colautti P, Cuttone G, Guatelli S, James B, Mazzucconi D, Rosenfeld AB, Selva A, Tran L, Petringa G. Microdosimetry of a therapeutic proton beam with a mini-TEPC and a MicroPlus-Bridge detector for RBE assessment. Phys Med Biol 2020; 65:245018. [PMID: 33086208 DOI: 10.1088/1361-6560/abc368] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Proton beams are widely used worldwide to treat localized tumours, the lower entrance dose and no exit dose, thus sparing surrounding normal tissues, being the main advantage of this treatment modality compared to conventional photon techniques. Clinical proton beam therapy treatment planning is based on the use of a general relative biological effectiveness (RBE) of 1.1 along the whole beam penetration depth, without taking into account the documented increase in RBE at the end of the depth dose profile, in the Bragg peak and beyond. However, an inaccurate estimation of the RBE can cause both underdose or overdose, in particular it can cause the unfavourable situation of underdosing the tumour and overdosing the normal tissue just beyond the tumour, which limits the treatment success and increases the risk of complications. In view of a more precise dose delivery that takes into account the variation of RBE, experimental microdosimetry offers valuable tools for the quality assurance of LET or RBE-based treatment planning systems. The purpose of this work is to compare the response of two different microdosimetry systems: the mini-TEPC and the MicroPlus-Bridge detector. Microdosimetric spectra were measured across the 62 MeV spread out Bragg peak of CATANA with the mini-TEPC and with the Bridge microdosimeter. The frequency and dose distributions of lineal energy were compared and the different contributions to the spectra were analysed, discussing the effects of different site sizes and chord length distributions. The shape of the lineal energy distributions measured with the two detectors are markedly different, due to the different water-equivalent sizes of the sensitive volumes: 0.85 μm for the TEPC and 17.3 μm for the silicon detector. When the Loncol's biological weighting function is applied to calculate the microdosimetric assessment of the RBE, both detectors lead to results that are consistent with biological survival data for glioma U87 cells. Both the mini-TEPC and the MicroPlus-Bridge detector can be used to assess the RBE variation of a 62 MeV modulated proton beam along its penetration depth. The microdosimetric assessment of the RBE based on the Loncol's weighting function is in good agreement with radiobiological results when the 10% biological uncertainty is taken into account.
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Affiliation(s)
- V Conte
- INFN Laboratori Nazionali di Legnaro, viale dell'Università 2 35020 Legnaro, Italy
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Bronk L, Guan F, Patel D, Ma D, Kroger B, Wang X, Tran K, Yiu J, Stephan C, Debus J, Abdollahi A, Jäkel O, Mohan R, Titt U, Grosshans DR. Mapping the Relative Biological Effectiveness of Proton, Helium and Carbon Ions with High-Throughput Techniques. Cancers (Basel) 2020; 12:cancers12123658. [PMID: 33291477 PMCID: PMC7762185 DOI: 10.3390/cancers12123658] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/26/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022] Open
Abstract
Large amounts of high quality biophysical data are needed to improve current biological effects models but such data are lacking and difficult to obtain. The present study aimed to more efficiently measure the spatial distribution of relative biological effectiveness (RBE) of charged particle beams using a novel high-accuracy and high-throughput experimental platform. Clonogenic survival was selected as the biological endpoint for two lung cancer cell lines, H460 and H1437, irradiated with protons, carbon, and helium ions. Ion-specific multi-step microplate holders were fabricated such that each column of a 96-well microplate is spatially situated at a different location along a particle beam path. Dose, dose-averaged linear energy transfer (LETd), and dose-mean lineal energy (yd) were calculated using an experimentally validated Geant4-based Monte Carlo system. Cells were irradiated at the Heidelberg Ion Beam Therapy Center (HIT). The experimental results showed that the clonogenic survival curves of all tested ions were yd-dependent. Both helium and carbon ions achieved maximum RBEs within specific yd ranges before biological efficacy declined, indicating an overkill effect. For protons, no overkill was observed, but RBE increased distal to the Bragg peak. Measured RBE profiles strongly depend on the physical characteristics such as yd and are ion specific.
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Affiliation(s)
- Lawrence Bronk
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.B.); (B.K.); (K.T.); (J.Y.)
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (F.G.); (D.P.); (D.M.); (X.W.); (R.M.)
| | - Fada Guan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (F.G.); (D.P.); (D.M.); (X.W.); (R.M.)
| | - Darshana Patel
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (F.G.); (D.P.); (D.M.); (X.W.); (R.M.)
| | - Duo Ma
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (F.G.); (D.P.); (D.M.); (X.W.); (R.M.)
| | - Benjamin Kroger
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.B.); (B.K.); (K.T.); (J.Y.)
| | - Xiaochun Wang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (F.G.); (D.P.); (D.M.); (X.W.); (R.M.)
| | - Kevin Tran
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.B.); (B.K.); (K.T.); (J.Y.)
| | - Joycelyn Yiu
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.B.); (B.K.); (K.T.); (J.Y.)
| | - Clifford Stephan
- Texas A&M Institute of Biosciences and Technology High Throughput Research and Screening Center, Houston, TX 77030, USA;
| | - Jürgen Debus
- National Center for Tumor Diseases, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany; (J.D.); (A.A.); (O.J.)
| | - Amir Abdollahi
- National Center for Tumor Diseases, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany; (J.D.); (A.A.); (O.J.)
- Heidelberger Ionenstrahl Therapiezentrum, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany
| | - Oliver Jäkel
- National Center for Tumor Diseases, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany; (J.D.); (A.A.); (O.J.)
- Heidelberger Ionenstrahl Therapiezentrum, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (F.G.); (D.P.); (D.M.); (X.W.); (R.M.)
| | - Uwe Titt
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (F.G.); (D.P.); (D.M.); (X.W.); (R.M.)
- Correspondence: (U.T.); (D.R.G.); Tel.: +1-713-563-2558 (U.T.); +1-713-745-8795 (D.R.G.)
| | - David R. Grosshans
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.B.); (B.K.); (K.T.); (J.Y.)
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Correspondence: (U.T.); (D.R.G.); Tel.: +1-713-563-2558 (U.T.); +1-713-745-8795 (D.R.G.)
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Howard ME, Denbeigh JM, Debrot EK, Remmes NB, Herman MG, Beltran CJ. A High-Precision Method for In Vitro Proton Irradiation. Int J Part Ther 2020; 7:62-69. [PMID: 33274258 PMCID: PMC7707323 DOI: 10.14338/ijpt-20-00007.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 07/02/2020] [Indexed: 01/06/2023] Open
Abstract
Purpose Although proton therapy has become a well-established radiation modality, continued efforts are needed to improve our understanding of the molecular and cellular mechanisms occurring during treatment. Such studies are challenging, requiring many resources. The purpose of this study was to create a phantom that would allow multiple in vitro experiments to be irradiated simultaneously with a spot-scanning proton beam. Materials and Methods The setup included a modified patient-couch top coupled with a high-precision robotic arm for positioning. An acrylic phantom was created to hold 4 6-well cell-culture plates at 2 different positions along the Bragg curve in a reproducible manner. The proton treatment plan consisted of 1 large field encompassing all 4 plates with a monoenergetic 76.8-MeV posterior beam. For robust delivery, a mini pyramid filter was used to broaden the Bragg peak (BP) in the depth direction. Both a Markus ionization chamber and EBT3 radiochromic film measurements were used to verify absolute dose. Results A treatment plan for the simultaneous irradiation of 2 plates irradiated with high linear energy transfer protons (BP, 7 keV/μm) and 2 plates irradiated with low linear energy transfer protons (entrance, 2.2 keV/μm) was created. Dose uncertainty was larger across the setup for cell plates positioned at the BP because of beam divergence and, subsequently, variable proton-path lengths. Markus chamber measurements resulted in uncertainty values of ±1.8% from the mean dose. Negligible differences were seen in the entrance region (<0.3%). Conclusion The proposed proton irradiation setup allows 4 plates to be simultaneously irradiated with 2 different portions (entrance and BP) of a 76.8-MeV beam. Dosimetric uncertainties across the setup are within ±1.8% of the mean dose.
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Affiliation(s)
| | - Janet M Denbeigh
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA
| | | | | | - Michael G Herman
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA
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Parisi A, Sato T, Matsuya Y, Kase Y, Magrin G, Verona C, Tran L, Rosenfeld A, Bianchi A, Olko P, Struelens L, Vanhavere F. Development of a new microdosimetric biological weighting function for the RBE 10 assessment in case of the V79 cell line exposed to ions from 1H to 238U. Phys Med Biol 2020; 65:235010. [PMID: 33274727 DOI: 10.1088/1361-6560/abbf96] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
An improved biological weighting function (IBWF) is proposed to phenomenologically relate microdosimetric lineal energy probability density distributions with the relative biological effectiveness (RBE) for the in vitro clonogenic cell survival (surviving fraction = 10%) of the most commonly used mammalian cell line, i.e. the Chinese hamster lung fibroblasts (V79). The IBWF, intended as a simple and robust tool for a fast RBE assessment to compare different exposure conditions in particle therapy beams, was determined through an iterative global-fitting process aimed to minimize the average relative deviation between RBE calculations and literature in vitro data in case of exposure to various types of ions from 1H to 238U. By using a single particle- and energy- independent function, it was possible to establish an univocal correlation between lineal energy and clonogenic cell survival for particles spanning over an unrestricted linear energy transfer range of almost five orders of magnitude (0.2 keV µm-1 to 15 000 keV µm-1 in liquid water). The average deviation between IBWF-derived RBE values and the published in vitro data was ∼14%. The IBWF results were also compared with corresponding calculations (in vitro RBE10 for the V79 cell line) performed using the modified microdosimetric kinetic model (modified MKM). Furthermore, RBE values computed with the reference biological weighting function (BWF) for the in vivo early intestine tolerance in mice were included for comparison and to further explore potential correlations between the BWF results and the in vitro RBE as reported in previous studies. The results suggest that the modified MKM possess limitations in reproducing the experimental in vitro RBE10 for the V79 cell line in case of ions heavier than 20Ne. Furthermore, due to the different modelled endpoint, marked deviations were found between the RBE values assessed using the reference BWF and the IBWF for ions heavier than 2H. Finally, the IBWF was unchangingly applied to calculate RBE values by processing lineal energy density distributions experimentally measured with eight different microdosimeters in 19 1H and 12C beams at ten different facilities (eight clinical and two research ones). Despite the differences between the detectors, irradiation facilities, beam profiles (pristine or spread out Bragg peak), maximum beam energy, beam delivery (passive or active scanning), energy degradation system (water, PMMA, polyamide or low-density polyethylene), the obtained IBWF-based RBE trends were found to be in good agreement with the corresponding ones in case of computer-simulated microdosimetric spectra (average relative deviation equal to 0.8% and 5.7% for 1H and 12C ions respectively).
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Görte J, Beyreuther E, Danen EHJ, Cordes N. Comparative Proton and Photon Irradiation Combined with Pharmacological Inhibitors in 3D Pancreatic Cancer Cultures. Cancers (Basel) 2020; 12:cancers12113216. [PMID: 33142778 PMCID: PMC7692858 DOI: 10.3390/cancers12113216] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 10/23/2020] [Accepted: 10/29/2020] [Indexed: 12/16/2022] Open
Abstract
Simple Summary Due to higher precision and consequent sparing of normal tissue, pancreatic cancer patients might profit from proton beam radiotherapy, a treatment modality increasingly used. Since molecular data upon proton irradiation in comparison to standard photon radiotherapy are limited in pancreatic cancer, the aims of our study were to unravel differences in the effectiveness of photon versus proton irradiation and to exploit radiation type-specific molecular changes for radiosensitizing 3D PDAC cell cultures. Although protons showed a slightly higher effectiveness and a stronger induction of molecular alterations than photons, our results revealed a radiation-type independent sensitization of molecular-targeted agents selected according to the discovered molecular, radiation-induced alterations. Abstract Pancreatic ductal adenocarcinoma (PDAC) is a highly therapy-resistant tumor entity of unmet needs. Over the last decades, radiotherapy has been considered as an additional treatment modality to surgery and chemotherapy. Owing to radiosensitive abdominal organs, high-precision proton beam radiotherapy has been regarded as superior to photon radiotherapy. To further elucidate the potential of combination therapies, we employed a more physiological 3D, matrix-based cell culture model to assess tumoroid formation capacity after photon and proton irradiation. Additionally, we investigated proton- and photon-irradiation-induced phosphoproteomic changes for identifying clinically exploitable targets. Here, we show that proton irradiation elicits a higher efficacy to reduce 3D PDAC tumoroid formation and a greater extent of phosphoproteome alterations compared with photon irradiation. The targeting of proteins identified in the phosphoproteome that were uniquely altered by protons or photons failed to cause radiation-type-specific radiosensitization. Targeting DNA repair proteins associated with non-homologous endjoining, however, revealed a strong radiosensitizing potential independent of the radiation type. In conclusion, our findings suggest proton irradiation to be potentially more effective in PDAC than photons without additional efficacy when combined with DNA repair inhibitors.
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Affiliation(s)
- Josephine Görte
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine Carl Gustav Carus Technische Universität Dresden, 01307 Dresden, Germany; (J.G.); (E.B.)
- Institute of Radiooncology—OncoRay, Helmholtz-Zentrum Dresden—Rossendorf, 01328 Dresden, Germany
| | - Elke Beyreuther
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine Carl Gustav Carus Technische Universität Dresden, 01307 Dresden, Germany; (J.G.); (E.B.)
- Institute of Radiation Physics, Helmholtz-Zentrum Dresden—Rossendorf, 01328 Dresden, Germany
| | - Erik H. J. Danen
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden University, 2333CC Leiden, The Netherlands;
| | - Nils Cordes
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine Carl Gustav Carus Technische Universität Dresden, 01307 Dresden, Germany; (J.G.); (E.B.)
- Institute of Radiooncology—OncoRay, Helmholtz-Zentrum Dresden—Rossendorf, 01328 Dresden, Germany
- German Cancer Consortium, Partner Site Dresden: German Cancer Research Center, 69120 Heidelberg, Germany
- Department of Radiotherapy and Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
- Correspondence: ; Tel.: +49-351-458-7401; Fax: +49-351-458-7311
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Carabe A, Karagounis IV, Huynh K, Bertolet A, François N, Kim MM, Maity A, Abel E, Dale R. Radiobiological effectiveness difference of proton arc beams versus conventional proton and photon beams. Phys Med Biol 2020; 65:165002. [PMID: 32413889 DOI: 10.1088/1361-6560/ab9370] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This paper aims to demonstrate the difference in biological effectiveness of proton monoenergetic arc therapy (PMAT) compared to intensity modulated proton therapy (IMPT) and conventional 6 MV photon therapy, and to quantify this difference when exposing cells of different radiosensitivity to the same experimental conditions for each modality. V79, H1299 and H460 cells were cultured in petri dishes placed in the central axis of a cylindrical and homogeneous solid water phantom of 20 cm in diameter. For the PMAT plan, cells were exposed to 13 mono-energetic proton beams separated every 15° over a 180° arc, designed to deliver a uniform dose of higher LET to the petri dishes. For the IMPT plans, 3 fields were used, where each field was modulated to cover the full target. Cells were also exposed to 6 MV photon beams in petri dishes to characterize their radiosensitivity. The relative biological effectiveness of the PMAT plans compared with those of IMPT was measured using clonogenic assays. Similarly, in order to study the quantity and quality of the DNA damage induced by the PMAT plans compared to that of IMPT and photons, γ-H2AX assays were conducted to study the relative amount of DNA damage induced by each modality, and their repair rate over time. The clonogenic assay revealed similar survival levels to the same dose delivered with IMPT or x-rays. However, a systematic average of up to a 43% increase in effectiveness in PMAT plans was observed when compared with IMPT. In addition, the repair kinetic assays proved that PMAT induces larger and more complex DNA damage (evidenced by a slower repair rate and a larger proportion of unrepaired DNA damage) than IMPT. The repair kinetics of IMPT and 6 MV photon therapy were similar. Mono-energetic arc beams offer the possibility of taking advantage of the enhanced LET of proton beams to increase TCP. This study presents initial results based on exposing cells with different radiosensitivity to other modalities under the same experimental conditions, but more extensive clonogenic and in-vivo studies will be required to confirm the validity of these results.
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Affiliation(s)
- Alejandro Carabe
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, PA, United States of America. Author to whom any correspondence should be addressed
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Moftah B, Aldelaijan S, Shehadeh M, Alzorkany F, Alrumayan F, Alsbeih G, Alshabanah M, Seuntjens J, Tomic N, Devic S. Calibration of MTT assay in proton beams using radiochromic films. Phys Med 2020; 77:146-153. [PMID: 32861190 DOI: 10.1016/j.ejmp.2020.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/31/2020] [Accepted: 08/04/2020] [Indexed: 10/23/2022] Open
Abstract
PURPOSE This study provides methodology of calibrating as well as controlling the output for an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) colorimetric assay irradiated in a low energy proton beam using EBT3-model GAFCHROMICTM film, without correcting for quenching effect. METHODS A calibrated Markus ionization chamber was used to measure the depth dose and beam output for 26.5 MeV protons produced by a CS30 cyclotron. A time-controlled aluminum cylinder was added in front of the horizontal beam-exit serving as a radiation shutter. Following the TRS-398 reference dosimetry protocol for proton beams, the output was calibrated in water at a reference depth of 3 mm. EBT3 film was calibrated for doses up to 8 Gy at the same depth. To verify the dose distribution for each 96-well MTT assay plate, EBT3 film was placed at the reference depth during irradiation and cell doses were scaled by measured percent depth dose (PDD) data. RESULTS The radiochromic film dosimetry system in this study provides dose measurements with an uncertainty better than 3.3% for doses higher than 1 Gy. From a single exposure and utilizing the Gaussian shape of the beam, multiple dose points can be obtained within different wells of the same plate ranging from 6.9 Gy (sigma ∼4%) in the central well, and 2 Gy (sigma ∼8%) for wells positioned closer to the periphery. CONCLUSIONS We described a methodology for radiochromic film-based dose monitoring system, using low-energy protons, which can be used for the MTT assay in any proton beam, except within Bragg peak region.
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Affiliation(s)
- B Moftah
- Radiation Physics Section, Biomedical Physics Department, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia; Medical Physics Unit, McGill University, Montréal, Québec, Canada
| | - S Aldelaijan
- Radiation Physics Section, Biomedical Physics Department, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - M Shehadeh
- Radiation Physics Section, Biomedical Physics Department, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - F Alzorkany
- Radiation Physics Section, Biomedical Physics Department, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - F Alrumayan
- Cyclotron and Radiopharmaceuticals Department, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - G Alsbeih
- Radiation Biology Section, Biomedical Physics Department, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - M Alshabanah
- Oncology Centre, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - J Seuntjens
- Medical Physics Unit, McGill University, Montréal, Québec, Canada; Department of Oncology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | - N Tomic
- Medical Physics Unit, McGill University, Montréal, Québec, Canada; Department of Radiation Oncology, Jewish General Hospital, Montréal, Québec, Canada
| | - S Devic
- Medical Physics Unit, McGill University, Montréal, Québec, Canada; Department of Radiation Oncology, Jewish General Hospital, Montréal, Québec, Canada.
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Overall Survival After Treatment of Localized Prostate Cancer With Proton Beam Therapy, External-Beam Photon Therapy, or Brachytherapy. Clin Genitourin Cancer 2020; 19:255-266.e7. [PMID: 32972877 PMCID: PMC7914293 DOI: 10.1016/j.clgc.2020.08.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 08/19/2020] [Accepted: 08/22/2020] [Indexed: 01/22/2023]
Abstract
With limited high-level evidence, we carried out a comparative effectiveness study for the effect of proton beam therapy (PBT) on overall survival compared to external-beam radiotherapy (EBRT) and brachytherapy (BT) among patients with localized prostate cancer using a national database. PBT was associated with a significant overall survival benefit compared to EBRT and had a similar performance as BT.
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Jones B, Hill MA. The physical separation between the LET associated with the ultimate relative biological effect (RBE) and the maximum LET in a proton or ion beam. Biomed Phys Eng Express 2020; 6:055001. [DOI: 10.1088/2057-1976/ab9e13] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Mein S, Klein C, Kopp B, Magro G, Harrabi S, Karger CP, Haberer T, Debus J, Abdollahi A, Dokic I, Mairani A. Assessment of RBE-Weighted Dose Models for Carbon Ion Therapy Toward Modernization of Clinical Practice at HIT: In Vitro, in Vivo, and in Patients. Int J Radiat Oncol Biol Phys 2020; 108:779-791. [PMID: 32504659 DOI: 10.1016/j.ijrobp.2020.05.041] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/02/2020] [Accepted: 05/21/2020] [Indexed: 12/13/2022]
Abstract
PURPOSE Present-day treatment planning in carbon ion therapy is conducted with assumptions for a limited number of tissue types and models for effective dose. Here, we comprehensively assess relative biological effectiveness (RBE) in carbon ion therapy and associated models toward the modernization of current clinical practice in effective dose calculation. METHODS Using 2 human (A549, H460) and 2 mouse (B16, Renca) tumor cell lines, clonogenic cell survival assay was performed for examination of changes in RBE along the full range of clinical-like spread-out Bragg peak (SOBP) fields. Prediction power of the local effect model (LEM1 and LEM4) and the modified microdosimetric kinetic model (mMKM) was assessed. Experimentation and analysis were carried out in the frame of a multidimensional end point study for clinically relevant ranges of physical dose (D), dose-averaged linear energy transfer (LETd), and base-line photon radio-sensitivity (α/β)x. Additionally, predictions were compared against previously reported RBE measurements in vivo and surveyed in patient cases. RESULTS RBE model prediction performance varied among the investigated perspectives, with mMKM prediction exhibiting superior agreement with measurements both in vitro and in vivo across the 3 investigated end points. LEM1 and LEM4 performed their best in the highest LET conditions but yielded overestimations and underestimations in low/midrange LET conditions, respectively, as demonstrated by comparison with measurements. Additionally, the analysis of patient treatment plans revealed substantial variability across the investigated models (±20%-30% uncertainty), largely dependent on the selected model and absolute values for input tissue parameters αx and βx. CONCLUSION RBE dependencies in vitro, in vivo, and in silico were investigated with respect to various clinically relevant end points in the context of tumor-specific tissue radio-sensitivity assignment and accurate RBE modeling. Discovered model trends and performances advocate upgrading current treatment planning schemes in carbon ion therapy and call for verification via clinical outcome analysis with large patient cohorts.
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Affiliation(s)
- Stewart Mein
- Clinical Cooperation Unit Translational Radiation Oncology, National Center for Tumor Diseases, Heidelberg University Hospital and German Cancer Research Center, Heidelberg, Germany; Division of Molecular and Translational Radiation Oncology, Department of Radiation Oncology, Heidelberg Faculty of Medicine and Heidelberg University Hospital, Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; German Cancer Consortium Core-Center Heidelberg, German Cancer Research Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, Heidelberg Institute of Radiation Oncology, National Center for Radiation Oncology, Heidelberg University and German Cancer Research Center, Heidelberg, Germany; Faculty of Physics and Astronomy, Heidelberg University, Germany
| | - Carmen Klein
- Clinical Cooperation Unit Translational Radiation Oncology, National Center for Tumor Diseases, Heidelberg University Hospital and German Cancer Research Center, Heidelberg, Germany; Division of Molecular and Translational Radiation Oncology, Department of Radiation Oncology, Heidelberg Faculty of Medicine and Heidelberg University Hospital, Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; German Cancer Consortium Core-Center Heidelberg, German Cancer Research Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, Heidelberg Institute of Radiation Oncology, National Center for Radiation Oncology, Heidelberg University and German Cancer Research Center, Heidelberg, Germany; Faculty of Biosciences, Heidelberg University, Germany
| | - Benedikt Kopp
- Clinical Cooperation Unit Translational Radiation Oncology, National Center for Tumor Diseases, Heidelberg University Hospital and German Cancer Research Center, Heidelberg, Germany; Division of Molecular and Translational Radiation Oncology, Department of Radiation Oncology, Heidelberg Faculty of Medicine and Heidelberg University Hospital, Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; German Cancer Consortium Core-Center Heidelberg, German Cancer Research Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, Heidelberg Institute of Radiation Oncology, National Center for Radiation Oncology, Heidelberg University and German Cancer Research Center, Heidelberg, Germany; Faculty of Physics and Astronomy, Heidelberg University, Germany
| | - Giuseppe Magro
- National Centre of Oncological Hadrontherapy, Medical Physics, Pavia, Italy
| | - Semi Harrabi
- Clinical Cooperation Unit Radiation Oncology, Heidelberg Institute of Radiation Oncology, National Center for Radiation Oncology, Heidelberg University and German Cancer Research Center, Heidelberg, Germany; National Center for Tumor Diseases, Heidelberg, Germany; Heidelberg Ion-Beam Therapy Center, Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Christian P Karger
- Clinical Cooperation Unit Translational Radiation Oncology, National Center for Tumor Diseases, Heidelberg University Hospital and German Cancer Research Center, Heidelberg, Germany; Department of Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg, Germany
| | - Thomas Haberer
- Heidelberg Ion-Beam Therapy Center, Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Jürgen Debus
- German Cancer Consortium Core-Center Heidelberg, German Cancer Research Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, Heidelberg Institute of Radiation Oncology, National Center for Radiation Oncology, Heidelberg University and German Cancer Research Center, Heidelberg, Germany; Faculty of Physics and Astronomy, Heidelberg University, Germany; National Center for Tumor Diseases, Heidelberg, Germany; Heidelberg Ion-Beam Therapy Center, Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Amir Abdollahi
- Clinical Cooperation Unit Translational Radiation Oncology, National Center for Tumor Diseases, Heidelberg University Hospital and German Cancer Research Center, Heidelberg, Germany; Division of Molecular and Translational Radiation Oncology, Department of Radiation Oncology, Heidelberg Faculty of Medicine and Heidelberg University Hospital, Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; German Cancer Consortium Core-Center Heidelberg, German Cancer Research Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, Heidelberg Institute of Radiation Oncology, National Center for Radiation Oncology, Heidelberg University and German Cancer Research Center, Heidelberg, Germany
| | - Ivana Dokic
- Clinical Cooperation Unit Translational Radiation Oncology, National Center for Tumor Diseases, Heidelberg University Hospital and German Cancer Research Center, Heidelberg, Germany; Division of Molecular and Translational Radiation Oncology, Department of Radiation Oncology, Heidelberg Faculty of Medicine and Heidelberg University Hospital, Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; German Cancer Consortium Core-Center Heidelberg, German Cancer Research Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, Heidelberg Institute of Radiation Oncology, National Center for Radiation Oncology, Heidelberg University and German Cancer Research Center, Heidelberg, Germany.
| | - Andrea Mairani
- Clinical Cooperation Unit Translational Radiation Oncology, National Center for Tumor Diseases, Heidelberg University Hospital and German Cancer Research Center, Heidelberg, Germany; National Centre of Oncological Hadrontherapy, Medical Physics, Pavia, Italy; Heidelberg Ion-Beam Therapy Center, Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.
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Biological dose-enhancement analysis with Monte Carlo simulation for Lipiodol for photon beams. Rep Pract Oncol Radiother 2020; 24:681-687. [PMID: 32467675 DOI: 10.1016/j.rpor.2019.10.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 08/01/2019] [Accepted: 10/07/2019] [Indexed: 11/24/2022] Open
Abstract
Background Previously, the physical dose-enhancement factor (DphysEF) enhancement was introduced. However, the dose enhancement considering the biological effectiveness was not shown. Purpose The aim of the current study was to evaluate the biological dose-enhancement factor (DbioEF) by the dose rate and to compare the DphysEF and the DbioEF in Lipiodol for liver Stereotactic Body Radiation Therapy (SBRT). Materials and methods Flattening-filter-free (FFF) 6-MV (6MVX) and 10MVX beams were delivered by TrueBeam. A virtual inhomogeneity phantom and a liver SBRT patient-treatment plan were used. The DphysEF and lineal energy distribution ( y ) distribution was calculated from Monte Carlo simulations. Using a microdosimetric-kinetic (MK) model that is estimated based on the linear-quadratic formula for Lipiodol using human liver hepatocellular cells (HepG2), the biological dose and biological dose enhancement factor (DbioEF) were calculated. The dose rate in the simulation was changed from 0.1 to 24 Gy/min. Results The DbioEF (DR:2Gy/min) and DphysEF with 10MVX FFF beam were 23.2% and 19.1% at maximum and 12.8% and 11.1% on average in the Lipiodol. In the comparison of the DbioEF between 0.1-24 Gy/min, the DbioEF was 21.2% and 11.1% with 0.1 Gy/min for 6MVX and 10 MVX, respectively. The DbioEF was larger than DEF for the 6MVX and 10MVX FFF beams. In clinical cases with the 10MVX FFF beam, the DbioEF and DphysEF in the Lipiodol region can increase the in-tumor dose by approximately 11% and 10%, respectively, without increasing the dose to normal tissue. Conclusions The lower-energy and higher-dose-rate beams were contributed to the biological dose. The Lipiodol caused the enhancement of the physical dose and biological effectiveness. Advances in knowledge The biological dose enhancement (DbioEF) should be considered in the high-density material such as the Lipiodol.
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Ytre-Hauge KS, Fjæra LF, Rørvik E, Dahle TJ, Dale JE, Pilskog S, Stokkevåg CH. Inter-patient variations in relative biological effectiveness for cranio-spinal irradiation with protons. Sci Rep 2020; 10:6212. [PMID: 32277106 PMCID: PMC7148381 DOI: 10.1038/s41598-020-63164-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/23/2020] [Indexed: 12/30/2022] Open
Abstract
Cranio-spinal irradiation (CSI) using protons has dosimetric advantages compared to photons and is expected to reduce risk of adverse effects. The proton relative biological effectiveness (RBE) varies with linear energy transfer (LET), tissue type and dose, but a variable RBE has not replaced the constant RBE of 1.1 in clinical treatment planning. We examined inter-patient variations in RBE for ten proton CSI patients. Variable RBE models were used to obtain RBE and RBE-weighted doses. RBE was quantified in terms of dose weighted organ-mean RBE ([Formula: see text] = mean RBE-weighted dose/mean physical dose) and effective RBE of the near maximum dose (D2%), i.e. RBED2% = [Formula: see text], where subscripts RBE and phys indicate that the D2% is calculated based on an RBE model and the physical dose, respectively. Compared to the median [Formula: see text] of the patient population, differences up to 15% were observed for the individual [Formula: see text] values found for the thyroid, while more modest variations were seen for the heart (6%), lungs (2%) and brainstem (<1%). Large inter-patient variation in RBE could be correlated to large spread in LET and dose for these organs at risk (OARs). For OARs with small inter-patient variations, the results show that applying a population based RBE in treatment planning may be a step forward compared to using RBE of 1.1. OARs with large inter-patient RBE variations should ideally be selected for patient-specific biological or RBE robustness analysis if the physical doses are close to known dose thresholds.
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Affiliation(s)
| | - Lars Fredrik Fjæra
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Eivind Rørvik
- Department of Medical Physics, Oslo University Hospital, The Radium Hospital, Oslo, Norway
| | - Tordis J Dahle
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Jon Espen Dale
- Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
| | - Sara Pilskog
- Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
| | - Camilla H Stokkevåg
- Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
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Beltran C, Schultz HL, Anand A, Merrell K. Radiation biology considerations of proton therapy for gastrointestinal cancers. J Gastrointest Oncol 2020; 11:225-230. [PMID: 32175125 DOI: 10.21037/jgo.2019.06.08] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Clinical enthusiasm for proton therapy (PT) is high, with an exponential increase in the number of centers offering treatment. Attraction for this charged particle therapy modality stems from the favorable proton dose distribution, with low radiation dose absorption on entry and maximum radiation deposition at the Bragg peak. The current clinical convention is to use a fixed relative biological effectiveness (RBE) value of 1.1 in order to correct the physical dose relative to photon therapy (i.e., proton radiation is 10% more biologically effective then photon radiation). In recent years, concerns about the potential side effects of PT have emerged. Various studies and review articles have sought to better quantify the RBE of PT and shine some light on the complexity of this problem. Reduction in biologic hot spots of non-target tissue is paramount in proton radiation therapy (RT) planning as the primary benefit of proton RT is a reduction in organ at risk (OAR) irradiation. New and emerging clinical data is in support of variable proton biological effectiveness and demonstrate late toxicity, presumably associated with high biological dose, to OAR. Overall, PT has promise to treat many cancer sites with similar efficacy as conventional RT but with fewer acute and late toxicities. However, further knowledge of biologic effective dose and its impact on both cancer and adjacent OAR is paramount for effective and safe treatment of patients with PT.
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Affiliation(s)
- Chris Beltran
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA
| | | | - Aman Anand
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, USA
| | - Kenneth Merrell
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA
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Ma D, Bronk L, Kerr M, Sobieski M, Chen M, Geng C, Yiu J, Wang X, Sahoo N, Cao W, Zhang X, Stephan C, Mohan R, Grosshans DR, Guan F. Exploring the advantages of intensity-modulated proton therapy: experimental validation of biological effects using two different beam intensity-modulation patterns. Sci Rep 2020; 10:3199. [PMID: 32081928 PMCID: PMC7035246 DOI: 10.1038/s41598-020-60246-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 01/30/2020] [Indexed: 02/07/2023] Open
Abstract
In current treatment plans of intensity-modulated proton therapy, high-energy beams are usually assigned larger weights than low-energy beams. Using this form of beam delivery strategy cannot effectively use the biological advantages of low-energy and high-linear energy transfer (LET) protons present within the Bragg peak. However, the planning optimizer can be adjusted to alter the intensity of each beamlet, thus maintaining an identical target dose while increasing the weights of low-energy beams to elevate the LET therein. The objective of this study was to experimentally validate the enhanced biological effects using a novel beam delivery strategy with elevated LET. We used Monte Carlo and optimization algorithms to generate two different intensity-modulation patterns, namely to form a downslope and a flat dose field in the target. We spatially mapped the biological effects using high-content automated assays by employing an upgraded biophysical system with improved accuracy and precision of collected data. In vitro results in cancer cells show that using two opposed downslope fields results in a more biologically effective dose, which may have the clinical potential to increase the therapeutic index of proton therapy.
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Affiliation(s)
- Duo Ma
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Lawrence Bronk
- Departments of Radiation and Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Matthew Kerr
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Mary Sobieski
- Center for Translational Cancer Research, Texas A&M Health Science Center, Institute of Biosciences and Technology, Houston, TX, 77030, USA
| | - Mei Chen
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.,Department of Radiation Oncology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025, China
| | - Changran Geng
- Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
| | - Joycelyn Yiu
- Departments of Radiation and Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.,Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | - Xiaochun Wang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Narayan Sahoo
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Wenhua Cao
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Xiaodong Zhang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Clifford Stephan
- Center for Translational Cancer Research, Texas A&M Health Science Center, Institute of Biosciences and Technology, Houston, TX, 77030, USA
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - David R Grosshans
- Departments of Radiation and Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
| | - Fada Guan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
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Gutierrez A, Rompokos V, Li K, Gillies C, D’Souza D, Solda F, Fersht N, Chang YC, Royle G, Amos RA, Underwood T. The impact of proton LET/RBE modeling and robustness analysis on base-of-skull and pediatric craniopharyngioma proton plans relative to VMAT. Acta Oncol 2019; 58:1765-1774. [PMID: 31429359 PMCID: PMC6882303 DOI: 10.1080/0284186x.2019.1653496] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/04/2019] [Indexed: 11/04/2022]
Abstract
Purpose: Pediatric craniopharyngioma, adult base-of-skull sarcoma and chordoma cases are all regarded as priority candidates for proton therapy. In this study, a dosimetric comparison between volumetric modulated arc therapy (VMAT) and intensity modulated proton therapy (IMPT) was first performed. We then investigated the impact of physical and biological uncertainties. We assessed whether IMPT plans remained dosimetrically superior when such uncertainty estimates were considered, especially with regards to sparing organs at risk (OARs).Methodology: We studied 10 cases: four chondrosarcoma, two chordoma and four pediatric craniopharyngioma. VMAT and IMPT plans were created according to modality-specific protocols. For IMPT, we considered (i) variable RBE modeling using the McNamara model for different values of (α/β)x, and (ii) robustness analysis with ±3 mm set-up and 3.5% range uncertainties.Results: When comparing the VMAT and IMPT plans, the dosimetric advantages of IMPT were clear: IMPT led to reduced integral dose and, typically, improved CTV coverage given our OAR constraints. When physical robustness analysis was performed for IMPT, some uncertainty scenarios worsened the CTV coverage but not usually beyond that achieved by VMAT. Certain scenarios caused OAR constraints to be exceeded, particularly for the brainstem and optical chiasm. However, variable RBE modeling predicted even more substantial hotspots, especially for low values of (α/β)x. Variable RBE modeling often prompted dose constraints to be exceeded for critical structures.Conclusion: For base-of-skull and pediatric craniopharyngioma cases, both physical and biological robustness analyses should be considered for IMPT: these analyses can substantially affect the sparing of OARs and comparisons against VMAT. All proton RBE modeling is subject to high levels of uncertainty, but the clinical community should remain cognizant possible RBE effects. Careful clinical and imaging follow-up, plus further research on end-of-range RBE mitigation strategies such as LET optimization, should be prioritized for these cohorts of proton patients.
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Affiliation(s)
- A. Gutierrez
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - V. Rompokos
- Department of Radiotherapy Physics, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - K. Li
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - C. Gillies
- Department of Radiotherapy Physics, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - D. D’Souza
- Department of Radiotherapy Physics, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - F. Solda
- Department of Clinical Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - N. Fersht
- Department of Clinical Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Y.-C. Chang
- Department of Clinical Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - G. Royle
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - R. A. Amos
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - T. Underwood
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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Jones B, Hill MA. Physical characteristics at the turnover-points of relative biological effect (RBE) with linear energy transfer (LET). Phys Med Biol 2019; 64:225010. [PMID: 31665711 DOI: 10.1088/1361-6560/ab52a5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
This paper considers the kinematic physical characteristics of ionic beams for maximum relative bio-effectiveness (RBE). RBE studies, based on heterogenous cell survival studies at different laboratories and linear energy transfer (LET) conditions for proton, helium, carbon, neon and argon ions, have been further analysed to determine the LETU values where RBE is maximal and the LET-RBE relationship has a turnover point. The SRIM stopping power software and other classical equations are used to determine the particle velocities, kinetic energies and their effective ionic charges at LETU. The estimated mean LETU values increase with atomic number (Z). Each LETU has a unique relativistic velocity, β = v/c, the velocity v expressed as a fraction of the speed of light, (c), and which is non-linearly proportional to Z. For ions helium and heavier ions, these velocities indicate that the effective charge Z * is around 0.99 of the full Z value at each LETU, with remarkably stable velocities of 3-4 nm · fs-1 per nucleon, or around 6-8 nm · fs-1 per unit Z. For Z = 1, (protons and deuterium) some values fall outside these ranges but the result depends on the mix of proton and deuterium used in experiments. An alternative index of βA/Z 2 (A is the atomic mass number), suggests an average velocity of around 15 nm · fs-1 for each particle at LETU. These distances, traversed in the time of the radiochemical process initiation, are all within the dimensions of the nucleosome. Curve fitting of the data set provides a predictive equation for LETU for any ion, as LETU = 30.4 + [Formula: see text] (1 - Exp[-0.61 √ (Z - 1)]) when normalised to protons. These data can be extended to heavier ions such as silicon and iron and give values that are consistent with experimental data. Each ion probably has a unique LETU value. Kinematic studies show maximum bio-effectiveness occurs at particle velocities where electron stripping remains at around 99% and where the velocity per nucleon is around 3-4 nm · fs-1. This study enhances the limited prior knowledge about the physical conditions of particle beams that provide maximum bio-effectiveness, with applications in particle radiotherapy, radiation protection and space travel.
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Affiliation(s)
- Bleddyn Jones
- Gray Laboratory, Oxford Institute for Radiation Oncology and Biology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DG, United Kingdom. Author to whom any correspondence should be addressed
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48
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McNamara A, Willers H, Paganetti H. Modelling variable proton relative biological effectiveness for treatment planning. Br J Radiol 2019; 93:20190334. [PMID: 31738081 DOI: 10.1259/bjr.20190334] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Dose in proton radiotherapy is generally prescribed by scaling the physical proton dose by a constant value of 1.1. Relative biological effectiveness (RBE) is defined as the ratio of doses required by two radiation modalities to cause the same level of biological effect. The adoption of an RBE of 1.1. assumes that the biological efficacy of protons is similar to photons, allowing decades of clinical dose prescriptions from photon treatments and protocols to be utilized in proton therapy. There is, however, emerging experimental evidence that indicates that proton RBE varies based on technical, tissue and patient factors. The notion that a single scaling factor may be used to equate the effects of photons and protons across all biological endpoints and doses is too simplistic and raises concern for treatment planning decisions. Here, we review the models that have been developed to better predict RBE variations in tissue based on experimental data as well as using a mechanistic approach.
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Affiliation(s)
- Aimee McNamara
- Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, USA
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49
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Rørvik E, Thörnqvist S, Ytre-Hauge KS. The experimental dose ranges influence the LETd dependency of the proton minimum RBE (RBEmin). ACTA ACUST UNITED AC 2019; 64:195001. [DOI: 10.1088/1361-6560/ab369a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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50
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Mutter RW, Jethwa KR, Wan Chan Tseung HS, Wick SM, Kahila MMH, Viehman JK, Shumway DA, Corbin KS, Park SS, Remmes NB, Whitaker TJ, Beltran CJ. Incorporation of Biologic Response Variance Modeling Into the Clinic: Limiting Risk of Brachial Plexopathy and Other Late Effects of Breast Cancer Proton Beam Therapy. Pract Radiat Oncol 2019; 10:e71-e81. [PMID: 31494289 PMCID: PMC7734652 DOI: 10.1016/j.prro.2019.08.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/30/2019] [Accepted: 08/29/2019] [Indexed: 12/25/2022]
Abstract
Purpose: The relative biologic effectiveness (RBE) rises with increasing linear energy transfer toward the end of proton tracks. Presently, there is no consensus on how RBE heterogeneity should be accounted for in breast cancer proton therapy treatment planning. Our purpose was to determine the dosimetric consequences of incorporating a brachial plexus (BP) biologic dose constraint and to describe other clinical implications of biologic planning. Methods and Materials: We instituted a biologic dose constraint for the BP in the context of MC1631, a randomized trial of conventional versus hypofractionated postmastectomy intensity modulated proton therapy (IMPT). IMPT plans of 13 patients treated before the implementation of the biologic dose constraint (cohort A) were compared with IMPT plans of 38 patients treated on MC1631 after its implementation (cohort B) using (1) a commercially available Eclipse treatment planning system (RBE = 1.1); (2) an in-house graphic processor unit-based Monte Carlo physical dose simulation (RBE = 1.1); and (3) an in-house Monte Carlo biologic dose (MCBD) simulation that assumes a linear relationship between RBE and dose-averaged linear energy transfer (product of RBE and physical dose = biologic dose). Results: Before implementation of a BP biologic dose constraint, the Eclipse mean BP D0.01 cm3 was 107%, and the MCBD estimate was 128% (ie, 64 Gy [RBE = biologic dose] in 25 fractions for a 50-Gy [RBE = 1.1] prescription), compared with 100.0% and 116.0%, respectively, after the implementation of the constraint. Implementation of the BP biologic dose constraint did not significantly affect clinical target volume coverage. MCBD plans predicted greater internal mammary node coverage and higher heart dose than Eclipse plans. Conclusions: Institution of a BP biologic dose constraint may reduce brachial plexopathy risk without compromising target coverage. MCBD plan evaluation provides valuable information to physicians that may assist in making clinical judgments regarding relative priority of target coverage versus normal tissue sparing.
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Affiliation(s)
- Robert W Mutter
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota.
| | - Krishan R Jethwa
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | | | - Stephanie M Wick
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | | | - Jason K Viehman
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | - Dean A Shumway
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | | | - Sean S Park
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | | | | | - Chris J Beltran
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
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