Heterogeneous p53 expression/subclonal TP53 mutation: a proportion of G3 EEC or ambiguous carcinomas with an ultramutated or hypermutated genotype (either POLEmut or DMMR) can acquire a TP53 mutation later in the tumoral course, developing a subclonal TP53 mutation that may result in heterogenous p53 expression, with a combination of normal wild-type and abnormal patterns (overexpression and/or ‘null’ phenotype and/or cytoplasmic staining). This evidence concerns the gene TP53 and carcinoma.