[Evaluation of Response to Immune Checkpoint Inhibitor Monotherapy or Combination with Chemotherapy for Patients with Advanced Non-small Cell Lung Cancer and High PD-L1 Expression].

BACKGROUND

Immunotherapy represented by immune checkpoint inhibitors (ICIs) has been widely used in the treatment of lung cancer. There are controversies in clinical practice for patients with advanced non-small cell lung cancer (NSCLC) and high programmed cell death-ligand 1 (PD-L1) expression receiving ICIs monotherapy or combination chemotherapy.

METHODS

This study retrospectively analyzed the clinical data of 49 patients with advanced NSCLC and high PD-L1 expression. Immunohistochemistry was performed with 22C3 antibody, and the expression level of PD-L1 was evaluated according to tumor proportion score (TPS). Objective response rate (ORR) and progression free survival (PFS) were compared by groups of different clinical characteristics.

RESULTS

ORR of monotherapy and combination therapy group was 47.1% (8/17) and 43.8% (14/32), respectively, without statistical difference (P=0.825). The median PFS of monotherapy and combination therapy group was 8.0 months and 6.8 months, respectively, without statistical difference (P=0.502). Statistical analysis of predictors of immunotherapy for the patients showed first-line immunotherapy had better ORR than subsequent immunotherapy (12/19, 63.2% vs 10/30, 33.3%, P=0.041), however no difference in PFS. And there were no differences in ORR or PFS among groups of age, gender, smoking status, performance status (PS), pathological type, tumor size and tumor-node-metastasis (TNM) stage.

CONCLUSIONS

The therapeutic effect is similar between ICIs monotherapy and combination chemotherapy for patients with advanced NSCLC and high PD-L1 expression. ORR of first-line immunotherapy was better in patients with advanced NSCLC and high PD-L1 expression. The optimal treatment for this population remains further prospective clinical studies.