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  • Perspective
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Towards clinical translation of FLASH radiotherapy

Nature Reviews Clinical Oncology volume 19, pages 791–803 (2022)Cite this article

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Abstract

The ultimate goal of radiation oncology is to eradicate tumours without toxicity to non-malignant tissues. FLASH radiotherapy, or the delivery of ultra-high dose rates of radiation (>40 Gy/s), emerged as a modality of irradiation that enables tumour control to be maintained while reducing toxicity to surrounding non-malignant tissues. In the past few years, preclinical studies have shown that FLASH radiotherapy can be delivered in very short times and substantially can widen the therapeutic window of radiotherapy. This ultra-fast radiation delivery could reduce toxicity and thus enable dose escalation to enhance antitumour efficacy, with the additional benefits of reducing treatment time and organ motion-related issues, eventually increasing the number of patients who can be treated. At present, FLASH is recognized as one of the most promising breakthroughs in radiation oncology, standing at the crossroads between technology, physics, chemistry and biology; however, several hurdles make its clinical translation difficult, including the need for a better understanding of the biological mechanisms, optimization of parameters and technological challenges. In this Perspective, we provide an overview of the principles underlying FLASH radiotherapy and discuss the challenges along the path towards its clinical application.

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Fig. 1: FLASH radiotherapy and the therapeutic window.
Fig. 2: Radiation quality achieved with FLASH.
Fig. 3: Response of various tissues to different radiation modalities.
Fig. 4: Treatment of cutaneous lymphoma with FLASH radiotherapy.

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Acknowledgements

The authors thank L. Volz (GSI) and A. Quarz (GSI and TUDa) for their support in preparing figures, and F. Bochud, J. F. Germond, T. Boehlen, C. Bailat and R. Moeckli for fruitful scientific discussions.

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Authors and Affiliations

  1. Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland

    Marie-Catherine Vozenin & Jean Bourhis

  2. GSI Helmholtzzentrum für Schwerionenforschung, Biophysics Department, Darmstadt, Germany

    Marco Durante

  3. Technische Universität Darmstadt, Institute of Condensed Matter Physics, Darmstadt, Germany

    Marco Durante

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All authors contributed substantially to discussion of the content and wrote the article. M.-C.V. and M.D. researched data for the article, and reviewed and edited the manuscript before submission.

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Vozenin, MC., Bourhis, J. & Durante, M. Towards clinical translation of FLASH radiotherapy. Nat Rev Clin Oncol 19, 791–803 (2022). https://doi.org/10.1038/s41571-022-00697-z

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