Disparities in the prevalence of EGFR mutations and ALK rearrangements by racial-ethnic group in South Florida with a focus on Hispanic patients, 2011-2019.
Authors: Pinheiro Paulo S. , Liu Qinran , Medina Heidy , Cranford Hannah M. , Herna Stuart Joseph , Rodriguez Estelamari , Lopes Gilberto 
Published: July 2024

e20528 Background: We examined the prevalence and survival outcomes of EGFR+, ALK+, and receipt of Tyrosine Kinase Inhibitors (TKIs), among all 1,654 patients diagnosed with de novo advanced non-small-cell lung cancer (NSCLC) during 2011-2019 in 2 predominantly Hispanic healthcare institutions in South Florida: Sylvester Cancer Center and University of Miami Hospital. Methods: Tumor registry data was linked with genomic databases. Electronic medical records were further reviewed. We employed Cox regression to assess survival outcomes among patients with documented EGFR+ and ALK+ results. Results: There were 748 Hispanics, 697 Non-Hispanic (NH)-Whites, 173 NH-Blacks, 32 Asians, and 4 other race patients in our study. The overall prevalence for EGFR+ and ALK+ was 11.1% and 1.3%, respectively. During the study period, as many as 16.7% and 4.1% of all patients received either EGFR- or ALK-targeting TKIs, respectively. EGFR+ prevalence varied among racial groups, with 11.3% in NH-Whites, 9.8% in NH-Blacks, 10.7% in Hispanics, and 25.0% in Asians. Among Florida Hispanics, there were significant variations in EGFR+ results from 7.0-8.1% in Caribbean Hispanics (Cuba, Puerto Rico, Dominican Republic) to 14.0% among Mexican and Central Americans, and 22.9% among South Americans (p < 0.05). Among all 184 patients with EGFR+ results, 43.5% exhibited a deletion 19 mutation, 26.1% had an L838R mutation, 17.4% had an unspecified targetable mutation, and 13.0% had rarer mutation types. Notably, the proportion of never-smokers varied significantly by studied group: 13.8% among NH-Whites, 36.4% among South Americans, 41.9% Mexicans and Central Americans, and 62.5% among Asians (p < 0.05). Much of the inter-racial and intra-ethnic variation in EGFR+ prevalence could be attributed to smoking status, with more similar proportions observed when comparing never-smokers and ever-smokers separately. The ALK+ prevalence ranged from 0.9% in NH-Whites, 1.3% among Hispanics, 2.3% among NH-Blacks, to 6.3% in Asians. Both EGFR+ and ALK+ were more prevalent among non-smokers and women. Still, smokers accounted for approximately half of all targetable mutations for both EGFR+ (90 never-smokers; 94 smokers) and ALK+ (12 never-smokers; 10 smokers). After adjusting for age group, sex, smoking status, and race-ethnicity, both EGFR+ and ALK+ NSCLC subtypes exhibited a lower risk of death over time compared to EGFR-/ALK- cases (EGFR+ aHR 0.68 95%CI 0.56-0.81; ALK+ aHR: 0.41 95%CI 0.23-0.73). Conclusions: Smoking status significantly impacts the documented varying prevalence of EGFR+ and ALK+ by race-ethnicity. TKIs were extensively used in 2011-2019 even without evidence of targetable mutations. Current/history of smoking should not prevent the study of EGFR+/ALK+ mutations/rearrangements. Patients with targetable mutations experienced significantly improved survival outcomes.