Radiotherapy is the most widely used and effective anti-
tumor therapy, however it can damage healthy tissues surrounding the tumor. One approach to reducing damage to
healthy tissue involves
irradiation at
dose rates far exceeding those currently used in clinical contexts reduces
radiation-induced toxicities while maintaining an equivalent
tumor response. This is known as the FLASH effect. The mechanism responsible for reduced tissue
toxicity following FLASH radiotherapy (FLASH-RT) is still undetermined, multiple hypotheses have been suggested by linking the high
dose rate to rapid
oxygen depletion, immune response, reduction of
peroxyl radical lifetime, preservation of
normal tissue stem cells, etc. While effective,
proton therapy is underutilized, contributing to fewer than 2% of all
external beam radiation treatments. To overcome this shortcoming, provided are methods which utilize the highest energy layer and a universal range shifter (URS) to facilitate rapid spot arc therapy (RAPIDSPARC™).