Virtual Library

Start Your Search

Yuxiang Ma



Author of

  • +

    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
    • +

      P1.01-96 - Concurrent ALK/EGFR Alterations in Chinese Lung Cancers: Frequency, Clinical Features, and Differential Response to Therapy (ID 14344)

      16:45 - 18:00  |  Author(s): Yuxiang Ma

      • Abstract
      • Slides

      Background

      ALK rearrangement and EGFR alterations are oncogenic driver mutations in lung cancers. Generally considered mutually exclusive, some studies suggested that these two mutations might occur concomitantly. Limited studies have reported the underlying association of molecular features and drug response to EGFR-TKIs in lung cancers with such co-alterations. Here, we performed next-generation sequencing (NGS) analysis in Chinese lung cancer patients, and evaluated distinct features of EML4- vs. non-EML4-ALK fusions in EGFR-mutated cases.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      A retrospective review was performed on genomic profiling data from either tissue or plasma of 419 ALK-rearranged lung cancer patients, sequenced in a CLIA-certified laboratory from 2015 to 2017. Patient characteristics (n=21) and clinical outcomes of patients harboring concurrent EGFR and ALK alterations were collected.

      4c3880bb027f159e801041b1021e88e8 Result

      Among the 419 ALK-rearranged lung cancers, a total of 21 patients (5.01%) were detected harboring concurrent ALK and EGFR (exon 18-20) genomic alterations. The concomitant rate of EGFR in patients harboring EML4-ALK (3.06%, 11/359) was dramatically lower than in non-EML4-ALK patients (16.67%, 10/60, p<0.001). Four EML4-ALK and 1 non-EML4-ALK patients were found to have de novo ALK/EGFR co-mutations whereas 1 EML4-ALK and 3 non-EML4-ALK patients acquired their ALK alterations after EGFR TKI treatment. For dual-positive patients who received past EGFR-TKI with unknown ALK status before the treatment, EML4-ALK/EGFR patients (n=6) commonly had shorter PFS to EGFR-TKI as well as higher relative ALK/EGFR allele frequency compared to non-EML4-ALK/EGFR (n=6; mPFS, 5.45 vs 15 months, p=0.11; mRAF, 1.52 vs 0.41, p=0.01), suggesting that EML4-ALK was more likely to be de novo whereas non-EML4-ALK acquired after EGFR-TKI. In addition, we found that for 9 dual-positive patients who had prior first-generation EGFR-TKI treatment, the clinical efficacy of single TKI use varied greatly, and patients might benefit from combination therapy of ALK+EGFR TKIs.

      8eea62084ca7e541d918e823422bd82e Conclusion

      This study revealed that EML4-ALK/EGFR and non-EML4-ALK/EGFR co-alterations displayed distinct prevalence in Chinese lung cancer patients. Our analyses suggested that non-EML4-ALK might be an acquired gene alteration and function as a resistance mechanism to EGFR-TKI, which might explain the observed discrepancy in prevalence as our sequencing cohort consisted of both previously treated or untreated patients. In addition, we observed that patients with dual ALK/EGFR alterations may benefit from combinatorial TKIs therapy.

      6f8b794f3246b0c1e1780bb4d4d5dc53

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.