Inactivating mutations in KEAP1 or activating mutations in NFE2L2 lead to constitutive activation of this pathway, allowing tumor cells to neutralize reactive oxygen species (ROS) and withstand oxidative stress induced by SBRT or systemic therapy [37,38,39,40,41,42,43,44,45,46,47]. This evidence concerns the gene NFE2L2 and neoplasm.