Failure to use PD-L1 as a marker of response to immune CPIs may be related to the following reasons: the method for detecting and measuring the expression of PD-L1, the identification of a cut-off level for positivity, the predictive value of PD-L1 based on the type of cell expression (tumor, lymphocyte, dendritic cell, macrophage), the impact of tumor heterogeneity on the predictive value of PD-L1 and the evaluation of the PD-L1 expression on the primary tumor versus the recurrence. This evidence concerns the gene CD274 and neoplasm.