LAUSR

FLASH radiotherapy ) is a fascinating new irradiation method that uses ultrahigh dose rates to deliver large doses of radiation to (within normal tissue this method without compromising tumor-killing efficacy. This results in a markedly higher therapeutic index compared to conventional radiation delivery, which is administered at much lower dose rates and over minutes. Therefore, the ‘‘FLASH effect’’ has become a of great interest in radiotherapy and its 2 , 3 ). in a of preclinical studies in and in experimental animal models (e.g., mice, mini-pigs and cats) using electron irradiation, and with megavoltage photons and cyclotron-based protons, helium and even carbon ions. In the treatment of a first human patient with FLASH electrons has highly results, the feasibility of FLASH-RT in the clinic. Although the exact mechanism(s) underlying FLASH are unclear, it suggested that the high dose rates of radiation spare normal tissue via oxygen depletion (which causes