Abstract 3912
Background
15–40% of NSCLC patients harbor EGFR sensitizing mutations. Tyrosine kinase inhibitors (TKI) provide significant clinical benefit in this population, yet all patients will develop resistance. Liquid biopsy has been demonstrated to reliably identify somatic tumor associated EGFR mutations. Quantitative assessment of mutated EGFR driven tumors could potentially be used to monitor disease progression and assess therapeutic response.
Methods
129 patients (68 F/61 M) with tissue biopsy-proofed EGFR sensitizing mutation-positive lung adenocarcinoma who were treated with EGFR-TKI and had one before TKI treatment and at least three post TKI treatment/follow-up blood samples were included in the study. 71% (92/129) patients were non-smokers. Plasma samples were tested with the cobas® EGFR Mutation Test v2, and the Semi-Quantitative Index (SQI) values for each mutation were reported by the software for the target mutation. The SQI is able to reflect a trend in the plasma EGFR mutation load. Molecular progression (MP) is defined as two consecutive non-zero SQI values or detection of T790M.
Results
The most common EGFR mutations detected in the tissue were L858R (53%) and Exon 19 deletion (Ex19Del) (40%). One patient had both Ex19Del and T790M mutations. Plasma cfDNA analyses detected EGFR mutations in 74% (95/129) of the baseline samples. 64 of the 95 patients had MP. On average, MP was 42 days prior to clinical progression (CP) based on RECIST1.1. The PPV and NPV of using MP to predict CP were 84% and 68%, respectively. Analysis of the serial plasmas collected from patients who progressed while on 1st line TKI showed reappearance of the original EGFR sensitizing mutations with increasing SQI levels before emergence of a T790M mutation. T790M mutation was detected in 21% (27/129) of the patients on TKI treatment.
Conclusions
This study clearly demonstrated that monitoring EGFR mutation levels or changes in blood could be a meaningful approach to predict clinical progression for lung adenocarcinoma patients treated with EGFR-TKI. It warrants further studies to demonstrate the potential clinical utility of serial blood EGFR testing in NSCLC management.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5141 - Mutational profiling of tumor tissue and sequential plasma illustrates emergent clones during treatment in late stage small cell lung cancer (SCLC)
Presenter: Stephanie Yaung
Session: Poster Display session 1
Resources:
Abstract
5189 - Association between serum HGF levels and neutrophil counts in small cell lung cancer and their impact on survival
Presenter: Laura Moliner
Session: Poster Display session 1
Resources:
Abstract
3539 - Prognostic role of RLF/MYCL1 and circPVT1 in SCLC.
Presenter: Clelia Tiziana Storlazzi
Session: Poster Display session 1
Resources:
Abstract
3438 - High-biologically effective dose radiotherapy improve the survival of small cell lung cancer patients with brain metastases: a propensity-matching analysis
Presenter: Qingyang Zhuang
Session: Poster Display session 1
Resources:
Abstract
3232 - Phase 1 open-label study evaluating the safety, pharmacokinetics, and preliminary efficacy of ABBV-181 and rovalpituzumab tesirine (ROVA-T) in patients with small cell lung cancer
Presenter: Emiliano Calvo
Session: Poster Display session 1
Resources:
Abstract
3633 - Activity of the novel Aurora kinase B inhibitor AZD2811 in biomarker-defined models of small cell lung cancer
Presenter: Carminia Maria Della Corte
Session: Poster Display session 1
Resources:
Abstract
3745 - Multi-level proteomics identifies FABP5 as a primary chemoresistance mediator in extensive-stage small cell lung cancer
Presenter: Yamei Chen
Session: Poster Display session 1
Resources:
Abstract
5049 - CLEPSIDRA trial: a pilot, biomarker-guided study to assess safety, tolerability, dose finding and efficacy of iadademstat in combination with platinum-etoposide in patients with relapsed, extensive-stage small cell lung cancer
Presenter: Alejandro Navarro Mendivil
Session: Poster Display session 1
Resources:
Abstract
5997 - Phased Avelumab combined with chemotherapy as first-line treatment for patients with advanced small-cell lung cancer (SCLC): The PAVE study, a Hellenic Cooperative Oncology Group Study
Presenter: Helena Linardou
Session: Poster Display session 1
Resources:
Abstract
4502 - Tobacco use in lung cáncer (LC) patients (p) in Spain
Presenter: Enric Carcereny Costa
Session: Poster Display session 1
Resources:
Abstract