CD274 and breast carcinoma: Single-agent ICBs have produced durable responses in a small proportion of breast cancer patients.12,13 This may be augmented by the addition of cytotoxic chemotherapy (see companion manuscript; Page DB et al.), as evidenced by the recent FDA approval of atezolizumab with nab-paclitaxel for first line, metastatic, PD-L1+ TNBC using the Ventana assay (SP142).14