TP53 and neoplasm: Within this seemingly unfavourable high-risk group, tumours with a pathogenic variant in the exonuclease domain of POLE (POLEmut) have an excellent prognosis, whereas tumours that are mismatch repair deficient (MMRd) or have no specific molecular profile (NSMP) have an intermediate prognosis, and tumours with abnormal (mutant-type) immunohistochemical expression of p53 (p53abn) have a poor prognosis.7