PDCD1 and neoplasm: Cancer cells pass through ICIs, blocking the activation of T cells and their cytotoxic effects on the tumor, resulting in immune escape, particularly inhibitors of PD1 (programmed cell death protein 1) and PDL1 (programmed cell death protein ligand 1) [5] PD1 is a cell-surface immunoglobulin which is expressed on T cells and pro-B cells, causing lymphocyte death, and thereby, suppressing immune responses through binding to its receptor PDL1 [6].