An active host adaptive response is characterized by the existence of programmed cell death protein 1 (PD‐1)+/IFN‐γ+ cytotoxic T cells and IFN‐γ‐induced PD‐L1+ tumor cells (TCs), which predicts high response rate to anti‐PD‐1/L1 therapy. The gene discussed is IFNG; the disease is neoplasm.