TP53 and endometrial cancer: Endometrioid endometrial cancer, a typically lower histological grade disease, is associated with gene mutations in PTEN (50%–83%), PI3Kinase (PIK3CA, R1 and R2 40%–80%), KRAS (20%), and FGFR2 (12%) and microsatellite instability (20%), while TP53 mutations appear to be the key driver in serous lesions (~90% of nonendometrioid lesions) [6–9].