Despite the lack of a significant correlation between intratumoral PD-L1 expression and survival, PD-1/PD-L1 interactions in the tumor as measured by immune-Förster resonance energy transfer (iFRET) is more predictive of survival in metastatic melanoma and NSCLC patients receiving ICB, in line with findings in draining LNs (89, 100). This evidence concerns the gene CD274 and non-small cell lung carcinoma.