Table 1.

Current and promising prognostic biomarkers in non-small cell lung cancer (NSCLC) treatment.

Prognostic Biomarker	Current State of Development
PD-L1 expression	FDA-approved and fully implemented in clinical practice
Tumor mutational burden	Under investigation
Differential agretopicity index	Under investigation
STK11 mutations	Under investigation
High levels of tumor infiltrating lymphocytes (CD4+, CD8+, CD8+/CD4+ ratio)	Under investigation
Kynurenine/tryptophan ratios	Under investigation
Quinolinic acid concentrations	Under investigation
Gut microbiome	Under investigation