FLASH radiotherapy: A promising new method for radiotherapy (Review)

Lv,Yinghao; Lv,Yue; Wang,Zhen; Lan,Tian; Feng,Xuping; Chen,Hao; Zhu,Jiang; Ma,Xiao; Du,Jinpeng; Hou,Guimin; Liao,Wenwei; Yuan,Kefei; Wu,Hong

doi:10.3892/ol.2022.13539

FLASH radiotherapy: A promising new method for radiotherapy (Review)

Authors:
- Yinghao Lv
- Yue Lv
- Zhen Wang
- Tian Lan
- Xuping Feng
- Hao Chen
- Jiang Zhu
- Xiao Ma
- Jinpeng Du
- Guimin Hou
- Wenwei Liao
- Kefei Yuan
- Hong Wu
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Affiliations: Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China, Laboratory of Liver Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610000, P.R. China
Published online on: October 5, 2022 https://doi.org/10.3892/ol.2022.13539
Article Number: 419
Copyright: © Lv et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

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Abstract

Among the treatments for malignant tumors, radiotherapy is of great significance both as a main treatment and as an adjuvant treatment. Radiation therapy damages cancer cells with ionizing radiation, leading to their death. However, radiation‑induced toxicity limits the dose delivered to the tumor, thereby constraining the control effect of radiotherapy on tumor growth. In addition, the delayed toxicity caused by radiotherapy significantly harms the physical and mental health of patients. FLASH‑RT, an emerging class of radiotherapy, causes a phenomenon known as the ‘FLASH effect’, which delivers radiotherapy at an ultra‑high dose rate with lower toxicity to normal tissue than conventional radiotherapy to achieve local tumor control. Although its mechanism remains to be fully elucidated, this modality constitutes a potential new approach to treating malignant tumors. In the present review, the current research progress of FLASH‑RT and its various particular effects are described, including the status of research on FLASH‑RT and its influencing factors. The hypothetic mechanism of action of FLASH‑RT is also summarized, providing insight into future tumor treatments.

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