Author of

• 10923

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  P1.18 - Poster Session 1 - Pathology (ID 175)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Pathology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/28/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 10930

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    P1.18-007 - Multiplex testing of driver mutations in Non-Small Cell Lung Cancer (NSCLCs) of African-American (AA) patients (ID 1312)

    09:30 - 09:30  |  Author(s): M. Cote
    • Abstract

    Background
    Recently driver genetic alterations have been identified in NSCLC that can be targeted for therapeutic interventions. Previous reports have suggested that rates of certain mutations may vary according to ethnic background. We conducted multiplex testing of NSCLCs of AA and white patients to assess variability in the mutation rates by race.

    Methods
    We identified tumor tissues of 139 AA and 340 white NSCLC patients collected as part of three different institutional review board approved studies. Using the Sequenom MassArray system and a multiplexed panel, we analyzed tumor DNA for 214 oncogenic mutations in 26 genes previously identified in NSCLC. Estimated risk (Odds Ratios (OR)) of any mutation and specific gene mutations among AA patients compared to white patients were calculated after adjusting for age, sex, smoking status and histology (adenocarcinoma versus non-adenocarcinoma). Information on smoking status was unavailable on 45 patients and was not included in calculations of ORs for some genes (OR[b]).

    Results
    The median age at diagnosis was 60 vs 66 years in AA vs white patients; 42% of AA patients and 65% of white patients were males; 67% of AA patients and 49% of white patients had adenocarcinoma; 67% of AA patients and 85% of white patients had stage I/II NSCLC and 10% of AA patients and 6% of white patients were never smokers. 43% of the AA patients and 46% of white patients had at least one mutation detected (OR=0.8; 0.5-1.2). 19% of AA patients and 8% of white patients had more than 1 mutation detected (OR 2.1; 1.1-4.1) (Table 1). AA patients were more likely to harbor mutations in STK11 (LKB1) (OR=7.5; 3.1-18.2) and NOTCH1 (OR[b]=8.4; 2.2-31.7), and they were less likely to have MET mutations (OR[b]=0.2; 0.1-1.1) then white patients. While not statistically significant, AA had lower prevalence of Kras mutations (OR[b]=0.5, 0.2-1.0) and p53 mutations (OR= 0.7; 0.4-1.4). Table 1

    Outcome	OR for African American Race	95% CI	P
    Any driver mutation[a]	0.8	0.5-1.2	0.203
    >1 driver mutation[a]	2.1	1.1-4.1	0.036
    STK11 Mutation[a]	7.5	3.1-18.2	<.001
    P53 Mutation[a]	0.7	0.4-1.4	0.359
    Kras Mutation[b]	0.5	0.2-1.0	0.041
    NOTCH1 Mutation[b]	8.4	2.2-31.7	0.002
    MET mutation[b]	0.2	0.1-1.1	0.065
    [a]Adjusted for age, sex, ever/never smoking and adeno/non-adeno
    [b]Adjusted for age, sex, and adeno/non-adeno

    Conclusion
    Our analysis of NSCLCs shows that AAs were more likely to have multiple genetic mutations than whites and the mutation profile differs by race.