PRF1 and neoplasm: We demonstrate that in the absence of multiple pathways including type I IFN, tumor sensing of IFNγ, CD8+ T cell direct recognition of tumor MHC class I, perforin-granzyme-mediated cytotoxicity, and extrinsic death receptor signaling such as Fas/FasL IFNγ can still ultimately orchestrate long-term durable tumor control.