However, assessment of PD‐L1 alone does not suffice to predict the clinical outcomes, since it may be affected by the use of different definitions of PD‐L1 positivity, the absence of a standard staining procedure to quantify expression levels, and the limited representativeness of samples resulting from sampling variability and tumor heterogeneity,22 all of which could partly account for the variance among the research results. This evidence concerns the gene CD274 and neoplasm.