CD274 and endometrial cancer: While recent negative results of sizeable phase III randomized controlled trials seemingly marked epithelial ovarian cancers as “immunologically cold”, the programmed cell death protein 1 (PD-1) inhibitor pembrolizumab gained FDA approval for both programmed cell death ligand 1 (PD-L1)-positive recurrent cervical cancer and MMR-deficient endometrial cancer after progression to prior systemic therapy [1,2,3,4].