To further characterise the group of MMRd–p53abn ECs, we used sequencing data from the TCGA study, comparing analogous tumours with combined microsatellite instability and TP53 mutation (MMRd–p53abn EC, n = 23) with those with one of these defects in isolation (henceforth referred to as single‐classifier MMRd EC if microsatellite‐unstable and single‐classifier p53abn EC if TP53‐mutant). Here, TP53 is linked to neoplasm.