Vol 27, No 2 (2022)
Review paper
Published online: 2022-03-17

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FLASH radiotherapy: an emerging approach in radiation therapy

Natalia Matuszak12, Wiktoria Maria Suchorska12, Piotr Milecki13, Marta Kruszyna-Mochalska14, Agnieszka Misiarz5, Jacek Pracz5, Julian Malicki16
Rep Pract Oncol Radiother 2022;27(2):343-351.


FLASH radiotherapy (RT) is a technique involving the delivery of ultra-high dose rate radiation to the target. FLASH-RT has been shown to reduce radiation-induced toxicity in healthy tissues without compromising the anti-cancer effects of treatment compared to conventional radiation therapy. In the present article, we review the published data on FLASH-RT and discuss the current state of knowledge of this novel approach. We also highlight the technological constraints and complexity of FLASH-RT and describe the physics underlying this modality, particularly how technology supports energy transfer by ionising radiation (e.g., beam on/off sequence, pulse-energy load, intervals). We emphasise that current preclinical experience is mostly based on FLASH electrons and that clinical application of FLASH-RT is very limited. The incorporation of FLASH-RT into routine clinical radiotherapy will require the development of devices capable of producing FLASH photon beams.

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