The following submission statement was provided by /u/tonymmorley:

>"It delivers a dose of radiation that’s over 300 times higher than traditional radiation therapy in just a fraction of a second. This induces something called the “FLASH effect” — a not-entirely-understood phenomenon in which the radiation still attacks the tumor, but doesn’t harm surrounding tissue."

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>"Ultimately, the researchers believe FLASH radiotherapy would be most useful for treating cancers in the brain, lungs, or gastrointestinal area, as the tissues around those tumors are particularly vulnerable to damage from traditional radiation therapy."

Please reply to OP's comment here: https://old.reddit.com/r/Futurology/comments/ypx6jz/experimental_flash_cancer_treatment_aces_first/ivlb1up/