Of note, oncolytic Ad in combination with αPD-1 exhibited more potent tumor growth inhibition than combination therapy groups using different ICIs (αPD-L1 or αCTLA-4), elucidating that PD-1 blockade is the optimal ICI candidate to be used in conjunction with an oncolytic Ad in pancreatic cancer. This evidence concerns the gene PDCD1 and pancreatic neoplasm.