Preclinical studies have shown that blocking the PD-L1/PD-1 axis with anti-PD-L1 or anti-PD-1 antibodies promotes anti-tumor T cell responses in pancreatic carcinoma [10], B16 melanoma [11], and CT26 colon carcinoma [12]. This evidence concerns the gene PDCD1 and exocrine pancreatic carcinoma.