Research on Survival of A549 Tumor Cells Following Proton Beam Irradiation Using FLASH Radiotherapy and Conventional Dose Rate Irradiation

Abstract

FLASH radiotherapy is the innovative radiotherapy technique in which the short treatment times, few tens of milliseconds, are used to deliver a therapeutic dose of radiation to the tumor. This novel approach reduces damage and minimizes the dose to normal tissues surrounding the tumor and to tissues that are affected by radiation, whilst maintaining the treatment effect on cancer cells. This regimen may improve the level of local control of the tumor and lower the occurrence of side effects. To date, the exact radiobiological mechanisms underpinning the FLASH effect are not completely understood. The paper presents the results on the delivery of a high-intensity proton beam at an energy of 660 MeV produced by Phasotron, a proton accelerator at the Joint Institute for Nuclear Research, Dubna. This proton beam has been created to perform radiobiological studies involving cell cultures and small laboratory animals (mice, rats) using FLASH radiation. Also, the survival rates were compared between A549 cells irradiated at extremely high dose rates (FLASH technique) and those exposed to conventional irradiation with the lower dose rate. It was found that there is a difference between these groups of A549 cells in the survival rates. The magnitude of the FLASH effect is represented by a factor of different dose rates.