Author of

• 12441

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  P3.06 - Poster Session 3 - Prognostic and Predictive Biomarkers (ID 178)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Biology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/30/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 12449

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    P3.06-008 - Prognostic and Predictive Value of KRAS Mutations in Advanced Non-Small Cell Lung Cancer (ID 1089)

    09:30 - 09:30  |  Author(s): D.W. Hwang
    • Abstract

    Background
    Clinical implications of KRAS mutations in advanced non-small cell lung cancer remain unclear.

    Methods
    Kras mutation status was identified by direct sequencing test in 844 specimens that were diagnosed of NSCLC at Samsung Medical Center from 2006 to 2011. This study included stage IV NSCLC patients who were treated with systemic chemotherapy. We retrospectively evaluated the prognostic and predictive value of KRAS mutations in patients with advanced NSCLC.

    Results
    Among 484 patients with available results for both KRAS and EGFR mutations, 39 (8%) had KRAS and 182 (38%) EGFR mutations, with two cases having both mutations. The median overall survivals for patients with KRAS mutations, EGFR mutations, or both wild types were 7.7, 38.0, and 15.0 months, respectively (P < 0.001). The KRAS mutation was an independent poor prognostic factor in the multivariate analysis (hazard ratio=2.6, 95% CI: 1.8–3.7). Response rates and progression-free survival (PFS) for the pemetrexed-based regimen in the KRAS mutation group were 14% and 2.1 months, inferior to those (28% and 3.9 months) in the KRAS wild type group.

    Conclusion
    KRAS mutation tended to be associated with inferior treatment outcomes after gemcitabine-based chemotherapy, while there was no difference regarding taxane-based regimen. Although the clinical outcomes to EGFR tyrosine kinase inhibitors (TKIs) seemed to be better in patients with KRAS wild type than those with KRAS mutations, there was no statistical difference in response rates and PFS according to KRAS mutation status when EGFR mutation status was considered. Two patients with both KRAS and EGFR mutations showed partial response to EGFR TKIs. Although G12D mutation appeared more frequently in never smokers, there was no difference in clinical outcomes according to KRAS genotypes. These results suggested KRAS mutations have an independent prognostic value but a limited predictive role for EGFR TKIs or cytotoxic chemotherapy in advanced NSCLC.