Author of

• 25520

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  Poster Display session (Friday) (ID 65)

  • Event: ELCC 2018
  • Type: Poster Display session
  • Track:
  • Presentations: 1
  • Moderators:
  • Coordinates: 4/13/2018, 12:30 - 13:00, Hall 1

  • 25274

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    48P - Clinical characteristics of Korean lung cancer patients with programmed death-ligand 1 expression (ID 301)

    12:30 - 13:00  |  Presenting Author(s): H. Park
    • Abstract

    Background:
    Programmed death-ligand 1 (PD-L1) is a transmembrane protein binds to the programmed death-1 (PD-1) receptor and anti-PD-1 therapy enables the immune response against tumors. The aim of this study was to assess the clinical and pathologic characteristics of PD-L1 positive lung cancer patients in Korea.
    
    Methods:
    We retrospectively reviewed the clinical data of pathologically proven lung cancer patients, and collected 267 cases of formalin-fixed, paraffin-embedded tissue sample from single institution. PD-L1 expression was detected by immunohistochemical assay using Monoclonal Mouse Anti-PD-L1, Clone 22C3. PD-L1 protein expression is determined by using Tumor Proportion Score (TPS), the percentage of viable tumor cells showing partial or complete membrane staining. The specimen should be considered PD-L1 positive as TPS ≥ 50% of tumor cells. We categorized according to the percentage of TPS; more than 1% or 50%.
    
    Results:
    A total of 267 patients were enrolled and major histologic types were adenocarcinoma (ADC)(69.3%). The majority was smoker (67.4%) and clinical stage IV (60.7%). 31 (11.6%) cases of EGFR mutation and 17 (6.4%) cases of ALK FISH positive were included. The patients who showed TPS ≥ 1% and 50% were 116 (42%) and 58 (21%), respectively. More than 1% of TPS group was older than below (64.83 ± 9.38 vs. 61.73 ± 10.78, p = 0.014). More than 1% of TPS group was consisted of ADC (67.8%) and squamous cell carcinoma(SqC) (29.6%) histology. And more than 50% of TPS group was composed of ADC (72.4%), SqC (22.4%). More than 1% of TPS group was significantly older than less (64.83 ± 9.38 years vs. 61.73 ± 10.78 years, p = 0.014). The rate of poorly differentiated pathology was significantly higher in TPS ≥ 1% group (42(40.8%) vs. 32(25.8%)) and TPS ≥ 50% group (25(53.2%) vs. 49(27.2%)). There was no difference in smoking, EGFR mutation, ALK rearrangement status or biopsy site.
    
    Conclusions:
    In Korean lung cancer patients, PD-L1 positive group defined as TPS ≥ 1% was older than negative group. And major histology was poorly differentiated non-small cell lung cancer in both TPS ≥ 1% and 50% groups.
    
    Clinical trial identification:
    
    
    Legal entity responsible for the study:
    Chonnam National University Hospital, Hwasun
    
    Funding:
    Has not received any funding
    
    Disclosure:
    The author has declared no conflicts of interest.