Author of

• 25952

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  P2.15 - Treatment in the Real World - Support, Survivorship, Systems Research (Not CME Accredited Session) (ID 964)

  • Event: WCLC 2018
  • Type: Poster Viewing in the Exhibit Hall
  • Track:
  • Presentations: 1
  • Moderators:
  • Coordinates: 9/25/2018, 16:45 - 18:00, Exhibit Hall

  • 27255

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    P2.15-33 - Evaluation of Liquid Biopsies for Molecular Profiling in Patients (pts) with Advanced NSCLC: What Happens After Panel Testing by NGS? (ID 13011)

    16:45 - 18:00  |  Author(s): Jing Zhao
    • Abstract

    Background
    

    Molecular profiling is limited by tumor heterogeneity and access to sufficient tissue for comprehensive analysis. Circulating tumor DNA (ctDNA) is promising as a minimally-invasive liquid biopsy for testing gene alterations and monitoring personalised treatment strategies. Because of its high expense, translation of the sensitive and accurate next generation sequencing (NGS) into routine cancer care has been slow.

    a9ded1e5ce5d75814730bb4caaf49419 Method
    

    We retrospectively reviewed 60 advanced NSCLC pts who were performed gene test prior to treatment using tissue by ARMS. Blood collections (10ml K2-EDTA) were performed after disease progression and analysed by NGS using a 10-gene panel (EGFR, KRAS, BRAF, HER2, PIK3CA, ALK, ROS1, RET, MET and TP53). We evaluated the significance of the outcome of panel testing by NGS in guiding the subsequent treatment in clinical practice.

    4c3880bb027f159e801041b1021e88e8 Result
    

    Among 60 NSCLC pts, 39 were male, 28 were never-smokers, and 56 were adenocarcinoma. ctDNA profiling detected alterations in 50 pts (83%). TP53 (53%), EGFR (48%) and KRAS (15%) were the most common abnormalities detected. Additionally, MET (8%), ALK (3%), HER2 (3%) and PIK3CA (2%) mutations were detected, respectively. Sensitizing mutations were detected in 22 pts (37%) prior to treatment using tissue by the method of ARMS, including 20 EGFR mutations and 2 ALK fusions, and all pts received tyrosine kinase inhibitor (TKI) as first-line therapy. Among 20 EGFR mutant pts, T790M mutation was detected in 9 pts (45%), KRAS mutation was detected in 4 pts (20%), and TP53 mutation was detected in 12 pts (60%), while MET amplification was found in 1 pt (5%). 1 KRAS mutation and 1 TP53 mutation were detected in 2 ALK –TKI resistant pts, respectively. 28 pts (47%) reported as tissue negative had a positive liquid biopsy, including 4 MET 14 exon skipping mutations, 2 EGFR 19 DEL, 4 EGFR L858R and 1 EGFR L861Q, and 2 EGFR T790M mutations. The mutation abundance is all below 1%, except 2 EGFR 19 DEL and 4 L858R. Ten pts received TKIs; 2 got parcial responses, 5 stable diseases and 3 progressive disease.

    8eea62084ca7e541d918e823422bd82e Conclusion
    

    ctDNA can be used as a ‘liquid biopsy’ for molecular profiling of NSCLC pts, and NGS, as a highly sensitive method to detect mutations with low mutation abundance, can provide more chances to pts to receive precise treatment.

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