The role of PD-L1 expression as a predictive biomarker in advanced non-small-cell lung cancer: a network meta-analysis

Background: Tumor programmed death ligand one (PD-L1) expression has been studied in several trials in non-small-cell lung cancer. Methods: We assessed the potential role of PD-L1 expression according to Cochrane Collaboration's Guidelines. Results: 13 studies with 1979 patients were included. Among 915 PD-L1 negative patients this rate was 13% (RR 2.08; 95% CI: 1.49-2.91; p < 0.01). The response rate has increased concurrent to the PD-L1 expression (Pearson's correlation, r = 0.43). PD-L1 expression was also related to better 24-weeks progression-free rate (RR 0.79; 95% CI: 0.71-0.89) and a trend toward better 1-year overall survival rate (RR 0.96; 95% CI: 0.87-1.06). Conclusion: Taking this data in account, PD-L1 overexpression could not be currently considered a robust biomarker to tailor the immune checkpoint inhibitors treatment.