CD274 and non-small cell lung carcinoma: et al. reported positive PD-L1 expression in 27% of cases16 and Konrad P. et al. reported a rate of 32.5%.17 Most of the existing literature contradicts our findings, reporting positive PD-L1 expression in approximately 50%-70% of cases.18-20 PD-L1 protein expression varies significantly across clinical studies on NSCLC.