NFE2L2 and neoplasm: As with orthotopic and syngeneic tumours, [18F]FSPG retention was higher in the NRF2-mutant xenografts compared to WT (Fig. 5b and Supplementary Fig. 6), at 14.8 ± 2.8% ID/g and 7.0 ± 2.4% ID/g, respectively (n = 9–11 mice; p < 0.0001; Fig. 5c).