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Petrich C, Dimroth A, Kraus KM, Winter J, Matejcek C, Butzek M, Natour G, Ravichandran M, Zimmermann M, Aulenbacher K, Galek M, Wilkens J, Combs SE, Bartzsch S. Towards Clinical Translation of Microbeam Radiation Therapy (MRT) with a Compact Source. Int J Radiat Oncol Biol Phys 2023; 117:S38-S39. [PMID: 37784488 DOI: 10.1016/j.ijrobp.2023.06.308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) MRT is an innovative concept of spatially fractionated radiation therapy that has demonstrated substantially improved normal tissue tolerance while achieving local tumor control in a wealth of preclinical studies. In MRT a collimator shapes a few micrometers wide planar x-ray beams with a spacing of a few 100 µm. MRT has the potential to improve cancer treatment substantially. However, until now, only a few large 3rd generation synchrotrons provide beam parameters that would allow patient treatments and therefore, MRT has not yet become clinically available. For a clinical translation, compact x-ray sources are required, that produce high dose rate orthovoltage x-rays from a micrometer sized emitter. MATERIALS/METHODS We developed and built a first prototype of a line focus x-ray tube (LFxT) dedicated to preclinical MRT research. By exploiting the heat capacity limit, the LFxT can deliver dose rates above 100 Gy/s from a just 50 µm-wide focal spot without destroying the rapidly (>200 Hz) rotating x-ray target. A bespoke collimator splits the homogeneous x-ray field into 50 µm wide high-dose peaks separated by 350 µm wide low-dose troughs (valleys). While the prototype in our lab is restricted to a power of 90 kW and 10 Gy/s at 300 kVp, we have started the development of the first clinically usable LFxT-2 at 1.5 MW power and >100 Gy/s at 600 kVp beam quality. We investigated the clinical applicability of the LFxT-2 by performing retrospective treatment planning studies. In particular, we were examining, whether 600 kVp photons would suffice to meet clinical dose constraints in MRT treatments treatment scenarios for first clinical use of MRT. We coupled the open source platform 3D Slicer with an in-house developed dose calculation algorithm for MRT treatment planning. For comparability of spatially fractionated MRT doses with conventional broad beam treatments, the MRT dose was converted to equivalent uniform dose (EUD) and equivalent doses in 2-Gy-fractions (EQD2). The 3D Slicer RT toolkit enabled the dosimetric analysis based on dose volume histograms (DVHs). RESULTS We installed a preclinical prototype of the LFxT that is currently put into operation and commissioned. Simulations show the feasibility of the next generation LFxT-2 with more than 100 Gy/s peak dose rate. Planned MRT dose distributions with the LFxT-2 meet established radiotherapy dose constraints in many of the investigated clinical cases. However, treatment planning procedures are not yet optimal and require improvement. CONCLUSION In a next step, we will build the LFxT-2 and aim for first clinical MRT trials at this source. In order to further improve calculated MRT dose distributions, we will implement inverse treatment planning techniques.
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Affiliation(s)
- C Petrich
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Neutron Source Heinz Maier-Leibnitz (FRM II), Munich, Germany
| | - A Dimroth
- Research Centre Juelich, Juelich, Germany
| | - K M Kraus
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Institute of Radiation Medicine (IRM), Helmholtz Zentrum München (HMGU) GmbH German Research Center for Environmental Health, Neuherberg, Germany
| | - J Winter
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Institute for Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany
| | - C Matejcek
- Helmholtz Institute Mainz, Mainz, Germany
| | - M Butzek
- Research Centre Juelich, Juelich, Germany
| | - G Natour
- Research Centre Juelich, Juelich, Germany
| | - M Ravichandran
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Technical University of Munich, Munich, Germany
| | | | | | - M Galek
- University of Applied Sciences Munich, Munich, Germany
| | - J Wilkens
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany
| | - S E Combs
- Institute for Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany; Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - S Bartzsch
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Neutron Source Heinz Maier-Leibnitz (FRM II), Munich, Germany
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Bartzsch S, Ahmed M, Bicher S, Stewart RD, Schmid TE, Combs SE, Meyer J. Equivalent Uniform Dose (EUD) and the Evaluation of Cell Survival in Spatially Fractionated Radiotherapy (SFRT). Int J Radiat Oncol Biol Phys 2023; 117:e642. [PMID: 37785912 DOI: 10.1016/j.ijrobp.2023.06.2053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) SFRT has shown promise as a treatment modality to decrease normal tissue sparing without compromising tumor coverage, i.e., an increase in the therapeutic window compared to more conventional uniform radiation therapy (RT). The aim of this work is to examine and test several alternative bio-dosimetric parameters for the prediction of cell survival for normal-tissue and tumor cell lines irradiated in vitro with uniform and microbeam radiotherapy (MRT). MATERIALS/METHODS A bespoke tungsten collimator with 50 parallel, 50 µm wide slits and 400 µm slit spacing was mounted into an x-ray cabinet. Human fibroblast (MRC5) and two human tumor cell lines (LN18 and A549) were irradiated with a range of doses (< 10 Gy) for uniform and MRT (50um slits, 400um center spacing) using kV X-rays. Average, mean and valley dose as useful predictive metrics of cell survival are compared to the equivalent uniform dose (EUD) with biological parameters estimated from uniform-dose experiments. RESULTS We find that EUD, with linear-quadratic (LQ) model parameters, is more predictive for survival after SFRT than maximum, minimum or average dose. The maximum and average doses are correlated very poorly with in vitro cell survival. The difference in cell survival between uniform and MRT irradiation as a function of EUD is cell-type and dose dependent. The report results suggest that MRT is more effective at cell killing of tumor-cell lines than uniform irradiation for both tumor cell lines. However, MRT is less effective at killing normal tissue cells than uniform irradiation. CONCLUSION EUD is a superior predictor of in vitro cell survival than other metrics sometimes used in the SFRT literature, including mean dose, maximum dose, and valley dose. The reported studies provide some evidence that SFRT may increase the therapeutic ratio by producing spatial dose distributions that effectively reduce normal-tissue damage with little or no change in biological damage to tumor cells. Additional studies are needed to further extend and generalize our results and to test our conclusions against a larger dose range, low and high linear energy transfer (LET) radiations and additional cell lines.
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Affiliation(s)
- S Bartzsch
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Institute for Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany
| | - M Ahmed
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Institute for Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany
| | - S Bicher
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Institute for Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany
| | - R D Stewart
- Department of Radiation Oncology, University of Washington - Fred Hutchinson Cancer Center, Seattle, WA
| | - T E Schmid
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Institute for Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany
| | - S E Combs
- Department of Radiation Oncology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany; Institute for Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany
| | - J Meyer
- Department of Radiation Oncology, University of Washington - Fred Hutchinson Cancer Center, Seattle, WA
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Bartzsch S, Dimroth A, Winter J, Petrich C, Matejcek C, Zhang Y, Rieser J, Rötzer S, Krämer KL, Zimmermann M, Galek M, Butzek M, Aulenbacher K, Wilkens J, Combs S. THE LINE FOCUS X-RAY TUBE: AN X-RAY SOURCE FOR FLASH AND SPATIALLY FRACTIONATED RADIATION THERAPY. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01595-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Schmid T, Nguyen M, Dombrowsky A, Bicher S, Treibel F, Winter J, Ahmed M, Combs S, Bartzsch S. RADIOBIOLOGICAL MECHANISMS IN MICROBEAM RADIATION THERAPY (MRT). Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01623-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Romano M, Alunni-Fabbroni M, Barbone G, Bartzsch S, Bouchet A, Bunk O, Dinkel J, Djonov V, Eckhardt A, Giannini C, Giese A, Hirner-Eppeneder H, Hlushchuk R, Jacques L, Laissue J, Miettinen A, Mittone A, Ricke J, Ruf V, Sancey L, Wright M, Bravin A, Coan P. Spacial Fractionation A MULTISCALE AND MULTI-TECHNIQUE APPROACH FOR THE CHARACTERIZATION OF THE EFFECTS OF SPATIALLY FRACTIONATED X-RAY FLASH IRRADIATION IN LUNGS AND BRAINS. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01549-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Lang D, Peeken J, Combs S, Wilkens J, Bartzsch S. Deep learning based HPV status prediction on CT images. Phys Med 2021. [DOI: 10.1016/s1120-1797(22)00560-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Winter J, Kraus K, Ahmed M, Combs S, Wilkens J, Bartzsch S. PD-0933 Microbeam radiotherapy planning for a clinical lung tumor case. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)07212-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Schmid T, Dombrowsky A, Sammer M, Reindl J, Dollinger G, Bartzsch S, Combs S. PH-0439 An innovative strategy in cancer treatment: Proton minibeam radiation therapy. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)07330-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Day LRJ, Donzelli M, Pellicioli P, Smyth LML, Barnes M, Bartzsch S, Crosbie JC. A commercial treatment planning system with a hybrid dose calculation algorithm for synchrotron radiotherapy trials. Phys Med Biol 2021; 66:055016. [PMID: 33373979 DOI: 10.1088/1361-6560/abd737] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Synchrotron Radiotherapy (SyncRT) is a preclinical radiation treatment which delivers synchrotron x-rays to cancer targets. SyncRT allows for novel treatments such as Microbeam Radiotherapy, which has been shown to have exceptional healthy tissue sparing capabilities while maintaining good tumour control. Veterinary trials in SyncRT are anticipated to take place in the near future at the Australian Synchrotron's Imaging and Medical Beamline (IMBL). However, before veterinary trials can commence, a computerised treatment planning system (TPS) is required, which can quickly and accurately calculate the synchrotron x-ray dose through patient CT images. Furthermore, SyncRT TPS's must be familiar and intuitive to radiotherapy planners in order to alleviate necessary training and reduce user error. We have paired an accurate and fast Monte Carlo (MC) based SyncRT dose calculation algorithm with EclipseTM, the most widely implemented commercial TPS in the clinic. Using EclipseTM, we have performed preliminary SyncRT trials on dog cadavers at the IMBL, and verified calculated doses against dosimetric measurement to within 5% for heterogeneous tissue-equivalent phantoms. We have also performed a validation of the TPS against a full MC simulation for constructed heterogeneous phantoms in EclipseTM, and showed good agreement for a range of water-like tissues to within 5%-8%. Our custom EclipseTM TPS for SyncRT is ready to perform live veterinary trials at the IMBL.
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Affiliation(s)
- L R J Day
- School of Science, RMIT University, Melbourne, Australia
| | - M Donzelli
- The European Synchrotron Radiation Facility, ID17 Biomedical Beamline, Grenoble, France.,Institute of Cancer Research, London, United Kingdom
| | - P Pellicioli
- The European Synchrotron Radiation Facility, ID17 Biomedical Beamline, Grenoble, France.,Inserm UA7 STROBE, Grenoble Alps University, Grenoble, France.,Swansea University Medical School, Singleton Park, Swansea, United Kingdom
| | - L M L Smyth
- Department of Obstetrics and Gynaecology, University of Melbourne, Royal Women's Hospital, Melbourne, Australia
| | - M Barnes
- School of Science, RMIT University, Melbourne, Australia.,Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Australia.,The Australian Synchrotron, Imaging and Medical Beamline, Melbourne, Australia
| | - S Bartzsch
- Institute of Cancer Research, London, United Kingdom.,Technical University of Munich, Munich, Germany
| | - J C Crosbie
- School of Science, RMIT University, Melbourne, Australia
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Winter J, Wilkens J, Combs S, Bartzsch S. OC-0471: Optimization of a compact x-ray source for clinical microbeam radiation therapy. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)00493-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lang D, Peeken J, Spraker M, Nyflot M, Combs S, Wilkens J, Bartzsch S. PO-1579: Deep learning based gross tumor volume definition on planning CTs of soft tissue sarcoma. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)01597-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Day L, Barnes M, Smyth L, Donzelli M, Bartzsch S, Klein M, Butler D, Hausermann D, Ryan S, Crosbie J. PO-1791: Synchrotron Radiotherapy of Pet Cadavers at the Imaging and Medical Beamline. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)01809-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Pellicioli P, Bartzsch S, Donzelli M, Krisch M, Bräuer-Krisch E. High resolution radiochromic film dosimetry: Comparison of a microdensitometer and an optical microscope. Phys Med 2019; 65:106-113. [PMID: 31450120 DOI: 10.1016/j.ejmp.2019.08.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 11/16/2022] Open
Abstract
PURPOSE Microbeam radiation therapy is a developing technique that promises superior tumour control and better normal tissue tolerance using spatially fractionated X-ray beams only tens of micrometres wide. Radiochromic film dosimetry at micrometric scale was performed using a microdensitometer, but this instrument presents limitations in accuracy and precision, therefore the use of a microscope is suggested as alternative. The detailed procedures developed to use the two devices are reported allowing a comparison. METHODS Films were irradiated with single microbeams and with arrays of 50 µm wide microbeams spaced by a 400 µm pitch, using a polychromatic beam with mean energy of 100 keV. The film dose measurements were performed using two independent instruments: a microdensitometer (MDM) and an optical microscope (OM). RESULTS The mean values of the absolute dose measured with the two instruments differ by less than 5% but the OM provides reproducibility with a standard deviation of 1.2% compared to up to 7% for the MDM. The resolution of the OM was determined to be ~ 1 to 2 µm in both planar directions able to resolve pencil beams irradiation, while the MDM reaches at the best 20 µm resolution along scanning direction. The uncertainties related to the data acquisition are 2.5-3% for the OM and 9-15% for the MDM. CONCLUSION The comparison between the two devices validates that the OM provides equivalent results to the MDM with better precision, reproducibility and resolution. In addition, the possibility to study dose distributions in two-dimensions over wider areas definitely sanctions the OM as substitute of the MDM.
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Affiliation(s)
- P Pellicioli
- The European Synchrotron Radiation Facility, ID17 Biomedical Beamline, Grenoble, France; Inserm UA7 STROBE, Grenoble Alpes University, Grenoble, France; Swansea University Medical School, Singleton Park, Swansea SA2 8PP, United Kingdom.
| | - S Bartzsch
- Helmholtz-Centre Munich, Institute of Innovative Radiation Therapy, Munich, Germany; Klinikum rechts der Isar, Department for Radiation Oncology, Technical University of Munich, Germany
| | - M Donzelli
- The European Synchrotron Radiation Facility, ID17 Biomedical Beamline, Grenoble, France; ICR - The Institute of Cancer Research, London, United Kingdom
| | - M Krisch
- The European Synchrotron Radiation Facility, ID17 Biomedical Beamline, Grenoble, France
| | - E Bräuer-Krisch
- The European Synchrotron Radiation Facility, ID17 Biomedical Beamline, Grenoble, France
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Treibel F, Wilkens J, Bartzsch S, Combs S. PV-106 An optimized compact microbeam source for preclinical studies. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)30526-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Bartzsch S. SP-0353 Compact microbeam sources and microbeam treatment planning. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)30773-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Hombrink G, Wilkens J, Combs S, Bartzsch S. OC-0093 Microcavities in the lung affect the dose distribution in microbeam radiation therapy. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)30513-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Schmid T, Hellmundt F, Lemmer S, Ilicic K, Melzner M, Bartzsch S, Wilkens J, Combs S. PO-1081 Biological interaction of a static magnetic field (SMF) with ionizing irradiation. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31501-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Steel H, Box C, Oelfke U, Bartzsch S. PV-0568: Remarkable normal tissue sparing effects are seen in vitro in response to microbeam radiation. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)30878-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Merrem A, Bartzsch S, Laissue J, Oelfke U. Computational modelling of the cerebral cortical microvasculature: effect of x-ray microbeams versus broad beam irradiation. Phys Med Biol 2017; 62:3902-3922. [PMID: 28333689 PMCID: PMC6050522 DOI: 10.1088/1361-6560/aa68d5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 03/15/2017] [Accepted: 03/23/2017] [Indexed: 12/31/2022]
Abstract
Microbeam Radiation Therapy is an innovative pre-clinical strategy which uses arrays of parallel, tens of micrometres wide kilo-voltage photon beams to treat tumours. These x-ray beams are typically generated on a synchrotron source. It was shown that these beam geometries allow exceptional normal tissue sparing from radiation damage while still being effective in tumour ablation. A final biological explanation for this enhanced therapeutic ratio has still not been found, some experimental data support an important role of the vasculature. In this work, the effect of microbeams on a normal microvascular network of the cerebral cortex was assessed in computer simulations and compared to the effect of homogeneous, seamless exposures at equal energy absorption. The anatomy of a cerebral microvascular network and the inflicted radiation damage were simulated to closely mimic experimental data using a novel probabilistic model of radiation damage to blood vessels. It was found that the spatial dose fractionation by microbeam arrays significantly decreased the vascular damage. The higher the peak-to-valley dose ratio, the more pronounced the sparing effect. Simulations of the radiation damage as a function of morphological parameters of the vascular network demonstrated that the distribution of blood vessel radii is a key parameter determining both the overall radiation damage of the vasculature and the dose-dependent differential effect of microbeam irradiation.
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Affiliation(s)
- A Merrem
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für biophysikalische Chemie, Am Fassberg 11, 37077 Göttingen, Germany
- This work was carried out at the German Cancer Research Center, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
| | - S Bartzsch
- Klinikum Rechts der Isar, Ismaninger Str. 2, 81675 München, Germany
- The Institute of Cancer Research, Royal Marsden Hospital, Fulham Rd, London SW3 6JJ, United Kingdom
- This work was carried out at the German Cancer Research Center, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
| | - J Laissue
- University of Bern, Hochschulstrasse 4, 3012 Bern, Switzerland
| | - U Oelfke
- The Institute of Cancer Research, Royal Marsden Hospital, Fulham Rd, London SW3 6JJ, United Kingdom
- This work was carried out at the German Cancer Research Center, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
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Kieselmann J, Bartzsch S, Oelfke U. TU-AB-BRC-06: Dose Calculation in Curved Space. Med Phys 2016. [DOI: 10.1118/1.4957400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Bartzsch S, Eismann S, Oelfke U. WE-EF-BRA-08: Cell Survival in Modulated Radiation Fields and Altered DNA-Repair at Field Edges. Med Phys 2015. [DOI: 10.1118/1.4925987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Girst S, Marx C, Bräuer-Krisch E, Bravin A, Bartzsch S, Oelfke U, Greubel C, Reindl J, Siebenwirth C, Zlobinskaya O, Multhoff G, Dollinger G, Schmid TE, Wilkens JJ. Improved normal tissue protection by proton and X-ray microchannels compared to homogeneous field irradiation. Phys Med 2015; 31:615-20. [PMID: 25936621 DOI: 10.1016/j.ejmp.2015.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Revised: 04/02/2015] [Accepted: 04/10/2015] [Indexed: 11/30/2022] Open
Abstract
The risk of developing normal tissue injuries often limits the radiation dose that can be applied to the tumour in radiation therapy. Microbeam Radiation Therapy (MRT), a spatially fractionated photon radiotherapy is currently tested at the European Synchrotron Radiation Facility (ESRF) to improve normal tissue protection. MRT utilizes an array of microscopically thin and nearly parallel X-ray beams that are generated by a synchrotron. At the ion microprobe SNAKE in Munich focused proton microbeams ("proton microchannels") are studied to improve normal tissue protection. Here, we comparatively investigate microbeam/microchannel irradiations with sub-millimetre X-ray versus proton beams to minimize the risk of normal tissue damage in a human skin model, in vitro. Skin tissues were irradiated with a mean dose of 2 Gy over the irradiated area either with parallel synchrotron-generated X-ray beams at the ESRF or with 20 MeV protons at SNAKE using four different irradiation modes: homogeneous field, parallel lines and microchannel applications using two different channel sizes. Normal tissue viability as determined in an MTT test was significantly higher after proton or X-ray microchannel irradiation compared to a homogeneous field irradiation. In line with these findings genetic damage, as determined by the measurement of micronuclei in keratinocytes, was significantly reduced after proton or X-ray microchannel compared to a homogeneous field irradiation. Our data show that skin irradiation using either X-ray or proton microchannels maintain a higher cell viability and DNA integrity compared to a homogeneous irradiation, and thus might improve normal tissue protection after radiation therapy.
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Affiliation(s)
- S Girst
- Universität der Bundeswehr München, Neubiberg, Germany
| | - C Marx
- Department of Radiation Oncology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - E Bräuer-Krisch
- European Synchrotron Radiation Facility, Grenoble Cedex, France
| | - A Bravin
- European Synchrotron Radiation Facility, Grenoble Cedex, France
| | - S Bartzsch
- German Cancer Research Centre (DKFZ), Heidelberg, Germany; The Institute of Cancer Research, Sutton, United Kingdom
| | - U Oelfke
- German Cancer Research Centre (DKFZ), Heidelberg, Germany; The Institute of Cancer Research, Sutton, United Kingdom
| | - C Greubel
- Universität der Bundeswehr München, Neubiberg, Germany
| | - J Reindl
- Universität der Bundeswehr München, Neubiberg, Germany
| | - C Siebenwirth
- Universität der Bundeswehr München, Neubiberg, Germany; Department of Radiation Oncology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - O Zlobinskaya
- Universität der Bundeswehr München, Neubiberg, Germany
| | - G Multhoff
- Department of Radiation Oncology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - G Dollinger
- Universität der Bundeswehr München, Neubiberg, Germany
| | - T E Schmid
- Department of Radiation Oncology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - J J Wilkens
- Department of Radiation Oncology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
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Bartzsch S, Merrem A, Oelfke U. EP-1475: Computational modelling of the microvasculature: effects of microbeams versus broad beam irradiation. Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)41467-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Bräuer-Krisch E, Nemoz C, Brochard T, Renier M, Requardt H, Serduc R, LeDuc G, Bravin A, Bartzsch S, Fournier P, Cornelius I, Berkvens P, Crosbie J, Lerch M, Rosenfeld A, Donzelli M, Oelfke U, Bouchet A, Blattmann H, Kaser-Hotz B, Laissue J. Medical physics challenges within the Microbeam Radiation Therapy (MRT) project. Phys Med 2014. [DOI: 10.1016/j.ejmp.2014.07.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Bartzsch S, Bräuer-Krisch E, Lerch M, Oelfke U. PD-0275: The influence of phase space and polarisation on MRT dose distributions. Radiother Oncol 2013. [DOI: 10.1016/s0167-8140(15)32581-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bartzsch S, Oelfke U. MO-F-BRB-01: Convolution Based Dose Calculation in Microbeam Radiation Therapy. Med Phys 2011. [DOI: 10.1118/1.3613002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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