Proton FLASH radiotherapy

FLASH radiotherapy (FLASH-RT) is a treatment modality that delivers ultra-high dose rate and ultra-fast radiation for cancer treatment. Compared to conventional dose rate radiotherapy, FLASH-RT can yield similar efficacy for tumors and achieve normal tissue protection, translating to an increased therapeutic window. Due to this unique feature, FLASH-RT is attracting increasing attention from the radiotherapy community, both academia and industry. Due to its unique Bragg peak as well as intrinsic high dose rate, application of FLASH has more value and profound significance in proton therapy while achieving highly conformal dose deposition simultaneously. This article reviews research progress on FLASH-RT, relevant cell and animal studies, experimental conditions and results. Moreover, this article also investigates the potential biological mechanisms, technical challenges for implementation and potential clinical applications of FLASH-RT.