TNFRSF9 and neoplasm: In patients when the frequency of tumor-reactive T cells is low, strategies need to be brought forward with vaccinations (proper antigens with new generation of adjuvants), adoptive transfer of tumor-reactive T cells, and mechanisms to amplify T cell responses with co-stimulatory agents (such as CD137 agonist), survival cytokines, and means to tame immune tolerance mechanisms such as turning off regulatory T cells.