PD-L1 Expression Level Displays a Positive Correlation with Immune Response in Pancreatic Cancer.

The expression of PD-L1 could be a novel biomarker which predicts that patients are more likely to respond to immunotherapy. Our study investigated the relationship among clinicopathological characteristics, prognosis, PD-L1 expression levels, and FOXP3+ Treg infiltration. In addition, the relationship among clinicopathological characteristics, prognosis, PD-L1 expression levels, and FOXP3+ Treg infiltration was explored. Furthermore, the relationship between PD-L1 expression and FOXP3+ Treg infiltration was examined. We found that 41.3% of pancreatic cancer patients had PD-L1-positive staining; both PD-L1 expression levels and FOXP3+ Treg infiltration were significantly associated with depth of invasion, lymph node metastasis, distant metastasis, and pTNM. In addition, PD-L1 expression and FOXP3+ Treg infiltration also could be prognostic biomarkers for pancreatic cancer.