CD274 and breast cancer: Those results led to the FDA approval of atezolizumab in combination with nab-paclitaxel in PD-L1+ (SP142 IC≥1) metastatic TNBC, establishing the first ICB approval in breast cancer. More recently, pembrolizumab, in combination with different chemotherapy agents, was also approved for the treatment of locally advanced or metastatic TNBC, based on results from the KEYNOTE-355 trial (14).