CTLA4 and neoplasm: Using an orthoptic tumor models that are unresponsive to systemic administration of checkpoint blockade inhibitors targeting cytotoxic T lymphocyte antigen 4 (CTLA-4) and programmed death protein 1 (PD-1), we have shown that lymphatic delivery at equivalent doses of anti-CTLA-4 or anti-PD-1 (whether through intradermal administration or microneedle devices), also results in greater anti-tumor responses including reduced or eliminated metastasis (Kwon et al., 2019c; Francis et al., 2020; Mantilla-Rojas et al., 2022).