HAVCR2 and neoplasm: Many immune checkpoint molecules such as the cluster of differentiation 274 (CD274) that encodes for programmed death receptor-ligand 1 (PD-L1) protein [5], cytotoxic T-lymphocyte–associated antigen 4 (CTLA4) [6], cluster of differentiation 276 (CD276) [7], lymphocyte-activation gene 3 (LAG3) [8], and hepatitis A virus cellular receptor 2 (HAVCR2) [9] are known to block anti-tumor responses in the tumor microenvironment [3].