Background: In non-small-cell lung cancers (NSCLC) with programmed death-ligand 1 (PD-L1) expression on ≥ 50% of tumor cells, first-line treatment with the PD-1 inhibitor pembrolizumab improves survival compared with platinum-doublet chemotherapy. The expression level of PD-L1 is the most accurate and well-analyzed predictive biomarker of benefit from pembrolizumab, but not all patients respond. It is therefore necessary to identify new biomarkers that select the patients who benefit from this type of treatment.
Patients and methods: In this single center retrospective study, we analyzed the impact of PD-L1 expression levels, Lung Immune Prognostic Index (LIPI), Derived neutrophil to lymphocyte ratio (dNLR) and Platelet-to-Lymphocyte Ratio (PLR) on the clinical outcomes in patients who received commercial pembrolizumab as first-line treatment of NSCLC with a PD-L1 expression of ≥ 50% and negative for genomic alterations in the EGFR, ROS1 and ALK genes.
Results: Among 17 patients included in this analysis, the ORR was 41.2% [95% CI 29.3%-53.1%], the mPFS was 12 months (95% CI 6.98–17.01), and the mOS was 18 months (95%CI, 7.58-28.41). Patients with dNLR ≥ 3 showed significantly shorter mean PFS of 6.5 months as compared to those with dNLR <3 of 20.61 months (HR 0.40, 95% CI 0.18-0.88; p=0.022) and shorter mean OS of 8.96 months versus 27.60 months (HR 0.26, 95% CI 0.09-0.77; p=0,015). Patients with poor LIPI showed also significantly shorter mean PFS of 2.25 months as compared to those with good-intermediate LIPI of 15.71 months (HR 0.07, 95% CI 0.01-0.73; p=0.026) and shorter mean OS of 3.25 months vs 21.87 months (HR 0.13, 95% CI 0.02-0.83; p=0.03).
Conclusions: Among patients with NSCLC and PD-L1 expression of ≥ 50% treated with first-line pembrolizumab, clinical outcomes are significantly improved in NSCLCs with a dNLR <3 and good-intermediate LIPI. These findings are similar to other published studies.
Biomarkers, Pembrolizumab, PD-L1 ≥ 50%, Lung immune prognostic index (LIPI), Derived neutrophil to lymphocyte ratio (dNLR), Platelet-to-lymphocyte ratio (PLR) and non-small cell lung cancer (NSCLC)