POLE and endometrial cancer: In an effort to subclassify endometrial cancer, The Cancer Genome Atlas (TCGA) Program identified four distinct molecular subtypes of endometrial cancer: Polymerase ε (POLE) ultramutated, microsatellite instable (MSI) hypermutated, copy-number-low (CN-low) and copy-number-high (CN-high) cases [3].