PDCD1 and neoplasm: The rationale for combining NACT with checkpoint inhibitors targeting programmed cell death-1 (PD-1) or programmed death ligand-1 (PD-L1) is based on the presence of tumor-infiltrating lymphocytes in most cells expressing the targets for the immunomodulatory monoclonal antibodies, the abundance of tumor antigens available for cross-priming at the time of immunotherapy, and potential reinvigoration of T lymphocytes from the primary tumor infiltrate to tackle metastatic disease13–16.