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)

  • 17716

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    P2.03b-087 - PD-L1 Expression in Adenosquamous Lung Carcinoma and the Comparison with the Other Common Variants of Non-Small Cell Lung Cancer (ID 3992)

    14:30 - 14:30  |  Author(s): Z. Liang
    • Abstract

    Background:
    Adenosquamous lung carcinoma (ASC) is a hybrid tumor made of adenocarcinoma and squamous cell carcinoma in one tumor. It is a rare disease with poorer prognosis comparing with the other common variants of non-small cell lung cancer (NSCLC). There is a persisting need for identifying more effective targeted therapy methods. Immune check point therapy targeted PD-1 or PD-L1 has achieved promising results in advanced stage NSCLC. PD-L1 expression has been suggested as a potential biomarker to enrich patients who will benefit from these treatments. There is limited data regarding the expression of PD-L1 in lung ASC and its correlation with the driver oncogene changes.
    
    Methods:
    Protein expression of PD-L1 was examined by immunohistochemistry method using the VENTANA PD-L1 (SP263) Rabbit Monoclonal Antibody. Messenger RNA level of PD-L1 was evaluated by in situ hybridization method. EGFR, K-ras, and B-raf mutation were detected by real time PCR method. Tissue microarrays (TMAs) containing formalin fixed paraffin embedded (FFPE) NSCLC cases were used in this study.
    
    Results:
    This study included 51 cases of lung ASC, 133 cases of lung adenocarcinoma (AD), and 83 cases of lung squamous cell carcinoma (SCC), totally. PD-L1 expression rate in lung ASC at the mRNA level and the protein level is highly correlated, which the kappa coefficient of the two examination methods is 0.856 (P=0.000). For the 46 cases of lung ASC, which the glandular and squamous components were analyzed separately, PD-L1 expression were divergent and mainly occurred in the SCC component of lung ASC. PD-L1 expression rate in the SCC component of ASC is similar with the result of lung SCC (39% vs 29%, P=0.327); its expression rate in AD component of ASC is the same with the result of lung AD (13.7% vs 13.5%, P=1.000). There is no association between PD-L1 expression and clinicopathological characteristics in lung ASC, for example, sex, age, smoking status, clinical stage, prognosis, EGFR mutation, K-ras mutation, or B-raf mutation, et al.
    
    Conclusion:
    PD-L1 expression in the two components of lung ASC is divergent and more prone to be expressed in the SCC component. Lung ASC may be not suitable for the PD-L1 targeted therapy because of this divergent expression status.