This is supported by publications describing transient downregulation of CDX2 at the invasive tumour front / tumour buds followed by re-expression at the metastatic sites17,18 and a recent study demonstrating the additive prognostic impact when addressing the poorly differentiated clusters together with the main tumour.20 Together with an overrepresentation of CDX2-positive and CDX2-moderate expression in pMMR tumours, poor prognosis links these observations to the CMS4 group.21 The gene discussed is CDX2; the disease is neoplasm.