R-Score: A New Parameter to Assess the Quality of Variants’ Calls Assessed by NGS Using Liquid Biopsies
Next-generation sequencing (NGS) has enabled a deeper knowledge of the molecular landscape in non-small cell lung cancer (NSCLC), identifying a growing number of targetable molecular alterations in key genes. However, NGS profiling of liquid biopsies risk for false positive and false negative calls and parameters assessing the quality of NGS calls remains lacking. In this study, we have evaluated the positive percent agreement (PPA) between NGS and digital PCR calls when assessing EGFR mutation status using 85 plasma samples from 82 EGFR-positive NSCLC patients. According to our data, variant allele fraction (VAF) was significantly lower in discordant calls and the median of the absolute va…
NGS‐based liquid biopsy profiling identifies mechanisms of resistance to ALK inhibitors: a step toward personalized NSCLC treatment
Despite impressive and durable responses, nonsmall cell lung cancer (NSCLC) patients treated with anaplastic lymphoma kinase (ALK) inhibitors (ALK‐Is) ultimately progress due to development of resistance. Here, we have evaluated the clinical utility of circulating tumor DNA (ctDNA) profiling by next‐generation sequencing (NGS) upon disease progression. We collected 26 plasma and two cerebrospinal fluid samples from 24 advanced ALK‐positive NSCLC patients at disease progression to an ALK‐I. These samples were analyzed by NGS and digital PCR. A tool to retrieve variants at the ALK locus was developed (VALK tool). We identified at least one resistance mutation in the ALK locus in ten (38.5%) p…
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…
Clinical and molecular characteristics of the patients in the liquid biopsy study in mEGFR-NSCLC in a Spanish population (OPH-1).
e21515 Background: The liquid biopsy (LB) is an important tool in the diagnostic and follow up of the patients with non-small cell lung cancer (NSCLC) and can provide big information about the mutational variability of the disease during of the treatment. Methods: We conducted a multicenter study with 200 patients with EGFR-mutated NSCLC, treated with first-line TKI therapy. We analyse the ctDNA by dPCR pre-treatment, at 8 weeks, at 7 months and at the progression of the disease (PD). Results: A total of 200 patients (60% women / 40% men) were included. The median of age was 68-year. The never smokers were 56% and 34% ex-smokers. 92% of the cases were adenocarcinomas. According to the stag…
Comprehensive cross-platform comparison of methods for non-invasive EGFR mutation testing : results of the RING observational trial
Plasma samples from 72 EGFR‐mutant advanced NSCLC patients, collected upon progression to first‐line TKI, were analyzed by seven methodologies (two NGS‐based methods, three high‐sensitivity PCR‐based platforms, and two FDA‐approved methods). Our study demonstrates a good to excellent agreement between methodologies and supports the use of liquid biopsies for therapy decision‐making.
ctDNA levels before treatment predict survival in non-small cell lung cancer patients treated with a tyrosine kinase inhibitor.
9542 Background: Currently there is an intense debate concerning therapeutic strategies in EGFR positive NSCLC patients with advance disease. Osimertinib is superior to standard EGFR Tyrosine Kinase Inhibitors (TKIs) as first line treatment. However, it is yet unclear whether this option is superior to sequential treatment of a 1st or 2nd generation TKI followed by osimertinib. In order to clarify this issue it is important to identify which patients are at high risk of progression disease. Methods: This is a prospective, multicentre, cross-sectional study promoted by Spanish Lung Cancer Group. 698 plasma samples from 196 advanced NSCLC patients with tumors harboring an EGFR activating mut…