Prognostic Significance of NSCLC and Response to EGFR-TKIs of EGFR-Mutated NSCLC Based on PD-L1 Expression.

BACKGROUND/AIM: Recent clinical trials have shown that immune checkpoint blockades that target either PD-1 or PD-L1 yield remarkable responses in a subgroup of patients with non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

We retrospectively examined, by immunohistochemical analysis, 211 NSCLC samples. Using 32 independent samples, we also evaluated PD-L1 expression in NSCLC patients with EGFR gene mutations treated by EGFR-TKIs.

RESULTS

Overall survival of PD-L1-positive stages I-III NSCLC and stage I NSCLC and stages I-III squamous cell carcinoma (SQ) were significantly shorter than those of PD-L1-negative NSCLC (p<0.01 and p=0.02 and p=0.01, respectively). In stage I NSCLC and stages I-III SQ, PD-L1 expression was found to be independent predictor of death after multivariate analysis. Response to EGFR-TKIs was not significantly different between PD-L1-positive and PD-L1-negative NSCLC patients with EGFR mutations.

CONCLUSION

PD-L1 expression was a significant independent predictor of poor outcome in NSCLC patients.