TP53 and neoplasm: Molecular clustering of these ‘multiple classifier EC’ showed that POLEmut‐p53abn EC clustered together with POLEmut EC without TP53 alterations, and it was noted that p53‐IHC in these cases frequently showed ‘subclonal’ mutant‐like p53 expression.19 Subclonal expression was defined as abrupt and complete regional aberrant p53 expression, in which the subclonal region was at least 10% of the total tumour volume.