Influence of EGFR mutation status and PD-L1 expression in stage III unresectable non-small cell lung cancer treated with chemoradiation and consolidation durvalumab.

BACKGROUND: Consolidation durvalumab after concurrent chemoradiation is the standard of care for unresectable stage III non-small cell lung cancer (NSCLC) based on the PACIFIC trial. However, there have been reports in the literature suggesting the efficacy of the treatment differs in patients whose tumors harbor epidermal growth factor receptor (EGFR) mutations and in those with low programed death ligand-1 (PD-L1) expression. This study describes the survival outcomes for patients with unresectable stage III NSCLC treated with chemoradiation followed by durvalumab with a specific focus on EGFR mutation status and PD-L1 expression. METHODS: This retrospective observational study was conducted across six sites in Greater Sydney, Australia. It included all patients diagnosed with unresectable stage III NSCLC treated with chemoradiation and who received at least one cycle of durvalumab between January 2018 and September 2021. Patients were stratified according to EGFR mutation status and PD-L1 tumor proportion score (TPS) of 1%. RESULTS: Of the 145 patients included in the analysis, 15/145 (10%) patients harbored an EGFR mutation and 61/145 (42%) patients had PD-L1 TPS of <1%. At a median follow-up of 15.1 months from the start of durvalumab, median progression-free survival (PFS) in EGFR mutant versus wild-type patients was 7.5 and 33.9 months, respectively (hazard ratio [HR]: 2.7; 95% confidence intervals [95% CI] 1.2-5.7; p = .01). Overall survival (OS) was not different between EGFR mutant and wild-type patients. There was no statistically significant difference in PFS (HR .7, 95% CI .4-1.7, p = .43) or OS (HR .5, 95% CI .4-4.7, p = .16) between patients with PD-L1 TPS of <1% versus PD-L1 TPS of ≥1%. CONCLUSIONS: Our data adds to the growing evidence that suggests consolidation durvalumab after definitive chemoradiation may not be as efficacious in patients with EGFR-mutant tumors compared with EGFR wild-type NSCLC.

Elevated neutrophil-to-lymphocyte ratio (NLR) is associated with poorer progression-free survival in unresectable stage III NSCLC treated with consolidation durvalumab.

Sustained elevation in neutrophil-to-lymphocyte ratio (NLR) after initial chemoradiotherapy (CRT) has been shown to correlate with worse prognosis in a number of solid organ malignancies. Here, we conducted a retrospective observational cohort study involving six sites across Sydney, Australia, including all patients with unresectable stage III NSCLC treated with CRT and consolidation durvalumab between January 2018 and September 2021. Patients had NLR collected prior to CRT and prior to cycle one of durvalumab. We used an NLR value of 3 to stratify patients into high and low groups. Patients with sustained NLR were defined as those with values ≥3 at both timepoints. A total of 145 patients were included in the study. The median age of patients was 66 years with median follow-up of 15.1 months. The median PFS was 17.6 months in the pre-CRT NLR high cohort and not reached (NR) in the pre-CRT NLR low cohort (HR 1.99; p = 0.01). The median OS was 35.5 months in the high pre-CRT NLR cohort compared with 42.0 months in the low pre-CRT NLR cohort (HR 2.62; 95% CI: 1.23-5.56, p < 0.01). Median PFS for sustained NLR elevation was 17.1 months versus NR (HR 1.5; p < 0.01). Pre-CRT NLR and sustained NLR remained independently prognostic for PFS on multivariate analysis (p = 0.04, p = 0.01) respectively. Pre-CRT NLR and sustained NLR is associated with worse PFS outcomes in unresectable stage III NSCLC treated with CRT and durvalumab. Pre-CRT NLR is also associated with worse OS.

The Multiple Potential Biomarkers for Predicting Immunotherapy Response-Finding the Needle in the Haystack.

Immune checkpoint inhibitors (ICIs) are being increasingly utilised in a variety of advanced malignancies. Despite promising outcomes in certain patients, the majority will not derive benefit and are at risk of potentially serious immune-related adverse events (irAEs). The development of predictive biomarkers is therefore critical to personalise treatments and improve outcomes. A number of biomarkers have shown promising results, including from tumour (programmed cell death ligand 1 (PD-L1), tumour mutational burden (TMB), stimulator of interferon genes (STING) and apoptosis-associated speck-like protein containing a CARD (ASC)), from blood (peripheral blood mononuclear cells (PBMCs), circulating tumour DNA (ctDNA), exosomes, cytokines and metal chelators) and finally the microbiome.