Significance of Programmed Death Ligand 1 (PD-L1) Immunohistochemical Expression in Colorectal Cancer

The significance of programmed death ligand 1 (PD-L1) expression in the prognosis of patients with colorectal cancer remains to be determined. We assessed the levels of PD-L1 expression in tumor-infiltrating immune cells as well as tumor cells, and evaluated the association between PD-L1 expression and clinical outcome in 262 colorectal cancer patients. In univariate analysis, TNM stage (p