Macrophage function is orchestrated by activated T cells.8 T cell-associated cytokines such as interferon gamma (IFN-γ) stimulate macrophages to increase expression of major histocompatibility complex (MHC) molecules, costimulatory receptors, and the Th1-polarizing cytokine IL-12.9 Accordingly, checkpoint blockade-activated T cells dramatically alter phenotypes of tumor-associated macrophages (TAMs) and monocytes. This evidence concerns the gene IFNG and neoplasm.