The Cancer Genome Atlas Research Network has identified four molecularly distinct subgroups of endometrial carcinoma with different clinical outcomes: POLE ultramutated (polymerase-E exonuclease domain-mutant: POLE-mut), microsatellite instability hypermutated (mismatch repair-deficient: MMR-d), copy number high (p53-mutant/-abnormal: p53-abn), and copy number low (no specific molecular profile: NSMP) [6]. The gene discussed is POLE; the disease is endometrial carcinoma.