Marine Potez1, Audrey Bouchet2, Mélanie Flaender1, Claire Rome3, Nora Collomb3, Michael Grotzer4, Michael Krisch5, Valentin Djonov6, Jacques Balosso1, Emmanuel Brun1, Jean A Laissue7, Raphaël Serduc1. 1. Inserm UA7, Rayonnement synchrotron pour la recherche médicale (STROBE), Université Grenoble Alpes, Grenoble, France. 2. Inserm UA7, Rayonnement synchrotron pour la recherche médicale (STROBE), Université Grenoble Alpes, Grenoble, France; Institute of Anatomy, Group Tomographic and Clinical Anatomy, University of Bern, Bern, Switzerland. Electronic address: audrey.bouchet@inserm.fr. 3. Team Functional NeuroImaging and Brain Perfusion, Inserm, France; Grenoble Institut des Neurosciences, Université Grenoble Alpes, La Tronche, France. 4. Department of Oncology, University Children's Hospital of Zurich, Switzerland. 5. European Synchrotron Radiation Facility, Grenoble, France. 6. Institute of Anatomy, Group Tomographic and Clinical Anatomy, University of Bern, Bern, Switzerland. 7. University of Bern, Bern, Switzerland.
Abstract
PURPOSE: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly collimated synchrotron beam into arrays of parallel microbeams depositing several hundred grays. It appears relevant to combine MRT with a conventional treatment course, preparing a treatment scheme for future patients in clinical trials. The efficiency of MRT delivered after several broad-beam (BB) fractions to palliate F98 brain tumors in rats in comparison with BB fractions alone was evaluated in this study. METHODS AND MATERIALS: Rats bearing 106 F98 cells implanted in the caudate nucleus were irradiated by 5 fractions in BB mode (3 × 6 Gy + 2 × 8 Gy BB) or by 2 boost fractions in MRT mode to a total of 5 fractions (3 × 6 Gy BB + MRT 2 × 8 Gy valley dose; peak dose 181 Gy [50/200 μm]). Tumor growth was evaluated in vivo by magnetic resonance imaging follow-up at T-1, T7, T12, T15, T20, and T25 days after radiation therapy and by histology and flow cytometry. RESULTS: MRT-boosted tumors displayed lower cell density and cell proliferation compared with BB-irradiated tumors. The MRT boost completely stopped tumor growth during ∼4 weeks and led to a significant increase in median survival time, whereas tumors treated with BB alone recurred within a few days after the last radiation fraction. CONCLUSIONS: The first evidence is presented that MRT, delivered as a boost of conventionally fractionated irradiation by orthovoltage broad x-ray beams, is feasible and more efficient than conventional radiation therapy alone.
PURPOSE: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly collimated synchrotron beam into arrays of parallel microbeams depositing several hundred grays. It appears relevant to combine MRT with a conventional treatment course, preparing a treatment scheme for future patients in clinical trials. The efficiency of MRT delivered after several broad-beam (BB) fractions to palliate F98 brain tumors in rats in comparison with BB fractions alone was evaluated in this study. METHODS AND MATERIALS: Rats bearing 106 F98 cells implanted in the caudate nucleus were irradiated by 5 fractions in BB mode (3 × 6 Gy + 2 × 8 Gy BB) or by 2 boost fractions in MRT mode to a total of 5 fractions (3 × 6 Gy BB + MRT 2 × 8 Gy valley dose; peak dose 181 Gy [50/200 μm]). Tumor growth was evaluated in vivo by magnetic resonance imaging follow-up at T-1, T7, T12, T15, T20, and T25 days after radiation therapy and by histology and flow cytometry. RESULTS: MRT-boosted tumors displayed lower cell density and cell proliferation compared with BB-irradiated tumors. The MRT boost completely stopped tumor growth during ∼4 weeks and led to a significant increase in median survival time, whereas tumors treated with BB alone recurred within a few days after the last radiation fraction. CONCLUSIONS: The first evidence is presented that MRT, delivered as a boost of conventionally fractionated irradiation by orthovoltage broad x-ray beams, is feasible and more efficient than conventional radiation therapy alone.
Authors: Elisabeth Schültke; Michael Lerch; Timo Kirschstein; Falko Lange; Katrin Porath; Stefan Fiedler; Jeremy Davis; Jason Paino; Elette Engels; Micah Barnes; Mitzi Klein; Christopher Hall; Daniel Häusermann; Guido Hildebrandt Journal: J Synchrotron Radiat Date: 2022-05-18 Impact factor: 2.557
Authors: Felix Jaekel; Elke Bräuer-Krisch; Stefan Bartzsch; Jean Laissue; Hans Blattmann; Marten Scholz; Julia Soloviova; Guido Hildebrandt; Elisabeth Schültke Journal: Int J Mol Sci Date: 2022-07-28 Impact factor: 6.208
Authors: Munir A Al-Zeer; Franziska Prehn; Stefan Fiedler; Ulrich Lienert; Michael Krisch; Johanna Berg; Jens Kurreck; Guido Hildebrandt; Elisabeth Schültke Journal: Int J Mol Sci Date: 2022-09-01 Impact factor: 6.208