Author of

• 25921

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  P1.01 - Advanced NSCLC (Not CME Accredited Session) (ID 933)

  • Event: WCLC 2018
  • Type: Poster Viewing in the Exhibit Hall
  • Track:
  • Presentations: 1
  • Moderators:
  • Coordinates: 9/24/2018, 16:45 - 18:00, Exhibit Hall

  • 26333

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    P1.01-103 - Leukocyte Telomere Length as a Novel Biomarker in Advanced Lung Adenocarcinoma Patients Treated with Gefitinib (ID 11748)

    16:45 - 18:00  |  Author(s): Ji Li
    • Abstract

    Background
    

    Gefitinib is currently one of the mostly used epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) recommended for treating non-small cell lung cancer. However, drug resistance was observed among the majority of patients after initial treatment. The factors that predict treatment prognosis and drug resistance to EGFR-TKIs remain elusive. Leukocyte telomere length has been previously proved to be associated with lung cancer risk. However, it is still unclear whether telomere length can be used as biomarker of EGFR-TKIs therapy. The objective of this study is to exam the association between leukocyte relative telomere length (RTL) and prognosis or drug resistance of advanced lung adenocarcinoma to gefitinib treatment.

    a9ded1e5ce5d75814730bb4caaf49419 Method
    

    In this study, three hundred and sixty-nine patients with stage IIIB or IV lung adenocarcinoma were recruited between January 2009 and June 2013. All patients were treated with gefitinib orally at a daily dose of 250 mg as first-line monotherapy. Leukocyte RTL of each patient was measured using quantitative polymerase chain reaction (qPCR) protocol on an ABI PRISM 7900HT Sequence Detection System (Applied Biosystems) and calculated according to Cawthon’s formula. Differences in patients’ characteristics were calculated by Pearson’s χ² tests or Student’s t test. Cox proportional hazard regression analyses were used to calculate univariate and multivariate hazard ratios (HRs) and their 95% confidence interval (95% CIs). Multivariate analyses were adjusted for sex, age, smoking status and EGFR mutation status, as appropriate. Survival differences were examined using the log-rank test. A P value of less than 0.05 was used as the criterion of statistical significance, and all statistical tests were two-sided.

    4c3880bb027f159e801041b1021e88e8 Result
    

    Among 369 patients, EGFR mutations were positive in 181 patients (49.1%). Compared to long RTL, short leukocyte RTL was significantly associated with poor prognosis in all patients after gefitinib treatment (overall survival: 12.9 months vs. 17.8 months, P=1.2×10^-4; progression free survival: 7.8 months vs. 13.0 months, P=0.043 for log-rank test). Additionally, statistically significant association between short leukocyte RTL and shorten OS still existed among the EGFR mutant patients with gefitinib treatment (HR = 1.65, 95% CI=1.28-2.12; P = 0.006). Besides EGFR mutation status, short RTL also contributed to significantly elevated risk of gefitinib primary resistance (HR = 1.50, 95% CI = 1.05-2.15, P = 0.027).

    8eea62084ca7e541d918e823422bd82e Conclusion
    

    Our results highlight the potential of leukocyte RTL as a novel biomarker in advanced lung adenocarcinoma patients treated with EGFR-TKIs and the possibility of patient-tailored decisions based on leukocyte RTL.

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