Author of

• 20156

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  P1.07 - Immunology and Immunotherapy (ID 693)

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

  • 22684

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    P1.07-016 - Comparison of PD-L1 Immunohistochemical Staining between EBUS-TBNA and Resected Non-Small Cell Lung Cancer Specimens (ID 8964)

    09:30 - 09:30  |  Author(s): D.R. Nelson
    • Abstract

    Background:
    PD-L1 can be detected by immunohistochemical (IHC) analysis and has emerged as a biomarker that predicts which patients are more likely to respond to anti-PD-L1/PD-1 immunotherapies in non-small cell lung cancer (NSCLC)(1, 2). To date, there is no evidence to support or refute PD-L1 IHC staining on endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) samples. Our study aimed to establish the sensitivity, specificity, positive predictive value, and negative predictive value of PD-L1 IHC staining reliability on EBUS-TBNA samples, when compared to resected tumor specimens.
    
    Method:
    A retrospective review was performed on all patients who underwent an EBUS-TBNA of either a lymph node(s) or the tumor itself, who subsequently had surgical resection of their tumor between July 2006 through September 2016. Patients who had a concordant NSCLC EBUS-TBNA diagnosis with their resected tumor were included. Patients with small cell lung cancer were excluded. All EBUS-TBNA samples were obtained using Olympus EBUS bronchoscopes and a 22-gauge ViziShot needle (Olympus Medical Systems Corp., Tokyo, Japan). The Dako PD-L1 IHC 22C3 (Agilent Pathology Solutions) assay was used. A positive PD-L1 stain was defined as ≥1% of tumor cell positivity. EBUS-TBNA aspirates were compared with the surgically resected specimen to calculate the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).
    
    Result:
    We performed 5448 EBUS-TBNA procedures for lung cancer. Seventy patients were included in our analysis. To date, 23 cases have been stained and reviewed (Table). The sensitivity and specificity was 71% and 100%, respectively. The PPV and NPV were 100% and 69%, respectively. We expect to complete our analysis of all patients prior to the IASLC World Conference.

    Comparison of PD-L1 IHC stain between EBUS-TBNA samples and resected tumor specimen.

    	Resected tumor PD-L1 positive	Resected tumor PD-L1 negative
    EBUS-TBNA PD-L1 positive	10	0
    EBUS-TBNA PD-L1 negative	4	9

    
    
    Conclusion:
    Positive PD-L1 IHC staining on EBUS-TBNA aspirates appears to have a strong correlation with resected tumor specimen. When EBUS-TBNA aspirates are negative for PD-L1 staining, additional tumor specimens are required to confirm the PD-L1 status.