Clinical utility of plasma-based digital next-generation sequencing in patients with advance-stage lung adenocarcinomas with insufficient tumor samples for tissue genotyping

[Background] Approximately 30% of tumor biopsies from patients with advanced-stage lung adenocarcinomas yield insufficient tissue for successful molecular subtyping. We have analyzed the clinical utility of next-generation sequencing (NGS) of cell-free circulating tumor DNA (ctDNA) in patients with inadequate tumor samples for tissue genotyping. [Patients and methods] We conducted the study in a multi-institutional prospective cohort of clinically unselected patients with advanced-stage lung adenocarcinomas with insufficient tissue for EGFR, ALK or ROS1 genotyping across 12 Spanish institutions (n = 93). ctDNA NGS was carried out by Guardant Health (Guardant360, Redwood City, CA), using a h…

165P Baseline circulating myeloid-derived suppressor cells correlate with neutrophil-to-lymphocyte ratio and overall survival in advanced non-small cell lung cancer patients treated with immune checkpoint inhibitors

Clinical utility of plasma-based digital next-generation sequencing in oncogene-driven non-small-cell lung cancer patients with tyrosine kinase inhibitor resistance

[Objectives] Resistance to tyrosine-kinase inhibitors (TKIs) is a clinical challenge in patients with oncogene-driven non-small-cell lung cancers (NSCLC). We have analyzed the utility of next-generation sequencing (NGS) of cell-free circulating tumor DNA (ctDNA) to impact the clinical care of patients with TKI resistance.

Comprehensive cross-platform comparison of methodologies for noninvasive EGFR mutation testing: Results of the RING observational trial.

e21518 Background: Several platforms for non-invasive EGFR testing are currently used in the clinical setting, with sensitivities ranging from 30 to 100%. Comparison studies in prospective cohorts remain limited and reports evaluating mutant allelic fractions (MAFs) are particularly scarce. The RING observational trial (ClinicalTrials.gov identifier NCT03363139) was designed to comprehensively analyze the concordance between methodologies for EGFR mutation detection in blood. Methods: Seventy-two EGFR mutant NSCLC patients were enrolled in the trial. Plasma samples were prospectively collected at progression to first line Tyrosine Kinase Inhibitor and tested for EGFR mutations by 7 methodo…

Genome-wide profiling of non-smoking-related lung cancer cells reveals common RB1 rearrangements associated with histopathologic transformation in EGFR-mutant tumors.

The etiology and the molecular basis of lung adenocarcinomas (LuADs) in nonsmokers are currently unknown. Furthermore, the scarcity of available primary cultures continues to hamper our biological understanding of non-smoking-related lung adenocarcinomas (NSK-LuADs). We established patient-derived cancer cell (PDC) cultures from metastatic NSK-LuADs, including two pairs of matched EGFR-mutant PDCs before and after resistance to tyrosine kinase inhibitors (TKIs), and then performed whole-exome and RNA sequencing to delineate their genomic architecture. For validation, we analyzed independent cohorts of primary LuADs. In addition to known non-smoker-associated alterations (e.g. RET, ALK, EGFR…

Baseline circulating myeloid-derived suppressor cells subpopulations, neutrophils/lymphocytes ratio, and response to PD-1/PD-L1 inhibitor in non-small cell lung cancer patients.

e15042 Background: Inhibitors of immune checkpoint PD-1/PD-L1 (ICI) have become a care standard in non-small cell lung cancer (NSCLC). Despite promising results, some patients cannot take advantage of immunotherapy effects. Nowadays, neither predictive nor prognostic circulating biomarkers have been found in order to select patients or to predict response to ICI. Myeloid-derived suppressor cells (MDSC) are potent immunity suppressors and may represent both a potential prognostic and a predictive biomarker. We aimed to assess the role of pretreatment circulating MDSC subpopulations on ICI outcomes in NSCLC patients. Methods: 86 NSCLC patients treated with ICI and 10 healthy donors in 3 cent…