CD274 and neoplasm: Numerous studies revealed that in addition to PD-L1 expression stained by IHC, biomarkers such as the density of tumor-infiltrating lymphocytes (TIL), tumor mutation burden (TMB), mismatch repair (MMR) deficiency, IFN-γ signature, and the 18-gene T-cell–inflamed gene expression profiling (GEP) score have been associated with the treatment effect of anti-PD-1/PD-L1 therapy (29–32).