CD274 and non-small cell lung carcinoma: In our study, we showed the effect of pembrolizumab treatment as monotherapy in the first-line treatment of advanced or metastatic NSCL with PD-L1 TPS ≥50%, where the primary objective of the study was to illustrate disparities and therapeutic response between metastatic squamous and non-squamous NSCLC, according to the number and location of metastases and according to PD-L1 TPS positivity.