CD274 and neoplasm: However, only a few of them have been validated in a randomized setting and implemented in clinical practice, such as programmed cell death 1 ligand 1(PD-L1) expression, tumor mutation burden (TMB), and microsatellite instability.1,2 The predictive value of these biomarkers is not consistent across different types of cancer, indicating that other biological factors determining the efficacy of ICI remain undiscovered.