Author of

• 18974

  +

  P3.02 - Biology/Pathology (ID 620)

  • Event: WCLC 2017
  • Type: Poster Session with Presenters Present
  • Track: Biology/Pathology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/18/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)

  • 23959

    +

    P3.02-012 - Liquid Based Cytology (LBC) Specimens Were Useful for EGFR Mutation Test (ID 10305)

    09:30 - 09:30  |  Author(s): K. Yoshida
    • Abstract
    • Slides

    Background:
    Reliable EGFR mutation testing techniques are required to identify eligible patients for EGFR-TKI treatment. Nowadays, surgically resected tissues or biopsy specimens are mainly used for the molecular testing. However, the biopsy samples sometimes have a certain limitation and so the cytology specimens are chosen for EGFR testing instead. Plasma sample has also become an option in EGFR-TKI resistant cases in which often have difficulties to obtain the inadequate tumor yield. In this study, we evaluated the feasibilities of using cytology samples and plasma specimens the EGFR molecular testing.
    
    Method:
    Cytology samples were obtained from biopsy and cells were suspended into liquid-based cytology (LBC) media. Tumor contents in the samples were confirmed with Papanicolaou stained slides. Plasma samples were also collected from patients shortly before the tissue biopsy. EGFR mutations in these samples were analyzed by cobas EGFR Mutation Test v2. Also, EGFR testing result of tissue specimens of the patients corresponded were collected from the medical records measured by cobas EGFR Mutation Test v2 as references.The feasibilities of both cytology and plasma specimen were evaluated comparing the results with the tissue samples.
    
    Result:
    

    EGFR mutation rate of tissue, plasma and LBC

    	Tissue	Plasma	LBC
    EGFR mutation +	18	9	14
    EGFR mutation -	42	51	43
    Invalid	0	0	3
    Total	60	60	60
    Positive rate (%)	30.0	15.0	23.3

    One-hundred seven patients were registered to this study. 60 patients were enrolled to this study. EGFR mutation rates in tissue, cytology, and plasma were 30.0, 23.3 and 15.0 %, respectively. Concordance analysis was performed comparing cytology specimens and plasma specimens to the tissue samples. Overall concordance EGFR mutation status was 85.0 and 81.7%, respectively. A total 7 cytology specimens had discordances and 3 were invalid results. For plasma samples, discordants were found in11 samples but no invalids.
    
    Conclusion:
    Plasma was easy to obtain sample, but rate of detection was low. If a cancer cell is detected enough, LBC is useful for the examination for EGFR. Preservation of sample is easy, and re-useful for the examination, repeatedly.
    
    

    Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.