Author of

• 17629

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  P2.03b - Poster Session with Presenters Present (ID 465)

  • Event: WCLC 2016
  • Type: Poster Presenters Present
  • Track: Advanced NSCLC
  • Presentations: 1
  • Moderators:
  • Coordinates: 12/06/2016, 14:30 - 15:45, Hall B (Poster Area)

  • 17656

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    P2.03b-027 - Circulating Free DNA (cfDNA) Analysis from Patients with Advanced Lung Adenocarcinoma (ID 5827)

    14:30 - 14:30  |  Author(s): C.S. Moura
    • Abstract

    Background:
    Circulating tumour free DNA (cfDNA) is a noninvasive assessment that can be used as an alternative method for gene mutations detection in lung cancer patients and for real time therapeutic monitoring. Detection and quantification of such mutations is difficult and next generation sequencing (NGS) is a promising technology. Concordance between tumour tissue DNA (tDNA) and plasma cfDNA need to be studied and changes in cfDNA correlated with clinical evolution.
    
    Methods:
    Ion Ampliseq Colon and Lung panel was used for tissue biopsies and the new Oncomine Lung cfDNA assay for cfDNA samples. All amplified products were used to prepare libraries and sequenced using the Ion PGM or S5xl system. Selected results were confirmed with the QuantStudio 3D Digital PCR. Plasma cfDNA collected at the diagnosis and during disease´s evolution of patients with advanced adenocarcinoma was analysed. cfDNA mutations were compared with tDNA.
    
    Results:
    56 patients were included. In the tumour samples 24 activating EGFR mutations, 16 KRAS, 3 BRAF-V600E, 3 TP53, 1 STK11 and 1 PIK3CA were identified. 16 patients were classified as “wild type” (WT). Tumour derived genetic alterations could be identified in cfDNA with allelic frequencies as low as 0.01%. Among the 48 alterations detected on tDNA, 39 (81.3%) were found in cfDNA. Plasma detection failed in 6 EGFR and 3 KRAS. In 3 EGFR patients, concurrent alterations not identified in the tumour were detected: 1 combination with EGFR p.Glu746_Ala750del; 2 with T790M and 1 with ALK p.I1171N. A KRAS mutation was identified in 1 WT patient. cfDNA longitudinal variations are being studied and will be updated.
    
    Conclusion:
    Profiling cfDNA with Ion NSG technology is feasible, allowing the detection of molecular alterations associated with targeted therapy or valuable for disease´s monitoring. cfDNA has a good correlation with tumour DNA alterations, representing a true “liquid biopsy”. The application of NGS to tumour and plasma samples hold a large spectrum of clinical potentialities.