The OS benefit of PD-1/PD-L1 blockade versus standard-of-care treatment is significantly greater in PD-L1+ than PD-L1- tumors for five cancer types, including colorectal cancer (HRD = 1.01, P interaction [Pi] = 0.03), breast cancer (HRD = 0.42, Pi = 0.03), gastric cancer (HRD = 0.37, Pi = 0.01), melanoma (HRD = 0.31, Pi = 0.05), and esophageal cancer (HRD = 0.23, Pi < 0.01). This evidence concerns the gene CD274 and breast cancer.