TP53 and cancer: The Cancer Genome Atlas defined 4 important prognostic molecular subgroups in EC based on integrated genomic data: ultramutated tumors with polymerase epsilon (POLE; OMIM 174762) alteration, microsatellite instability (MSI), copy-number-high with frequent tumor protein p53 (TP53; OMIM 191170) alteration, and copy-number-low (also known as no specific molecular profile [NSMP]).