CD274 and neoplasm: These emerging biomarkers include PD-L1 expression on cancer cells, human papillomavirus (HPV) infection status, tumor mutational burden (TMB), tumor immune infiltration, T cell-inflamed gene expression profile (GEP), smoking history, microsatellite instability (MSI), circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) (Figure 1).