CD274 and neoplasm: In addition, the expression of programmed death ligand 1 (PD-L1) in tumor cells is regarded as a predictive marker for the response of the tumor to immunomodulatory therapies that target the programmed cell death 1 (PD-1)/PD-L1 pathway (43), with PD-L1 staining being diffusely positive in cases of EIMS (32).