Abstract A106: Disparities in the presence of driver mutations and response to tyrosine kinase inhibitors in young patients with lung cancer

Abstract Background: A concerning number of young patients (<50 years old) have been diagnosed with advanced lung cancer in recent years, likely due to driver mutations. This study examined disparities in the presence of driver mutations and response to tyrosine kinase inhibitors (TKI) in young patients with lung adenocarcinoma. Methods: This retrospective study included 98 patients (18-50 years old) with lung adenocarcinoma treated at the University of Miami Sylvester Comprehensive Cancer Center (2004-2023). Data from 81 patients with genetic information were analyzed. Patient demographics, clinical characteristics, and outcomes were collected. Chi- square and Kaplan-Meier methods were used, and p-values < 0.05 were considered significant. Results: Among the 17 patients without biomarker testing, 88% were white, 64.7% female and 59% Hispanic. The mean age at diagnosis for the 81 patients with genetic data was 41. Most were never smokers (56%), female (67%), white (83%), and Hispanic (52%) with stage IV disease (64%). At data cutoff in June 2023, 43 (53%) patients were alive, with a mOS of 27 months. Of the 81 patients, 58 (71.6%) had at least one driver mutation. The most common mutations were EGFR (31%), ALK (27%), and ROS1 (6%). No differences in mutation expression were found by gender, race, or ethnicity. Among patients with an actionable mutation, there were no significant differences in treatment with a TKI by race (p=0.337), gender (p=0.347), or ethnicity (p=0.940). However, 50% of eligible Black patients were not treated with a TKI compared to 26% of white patients. TKI as first-line treatment did not significantly vary by race (p=0.551), gender (p=0.883), or ethnicity (p=0.062), but 53% of white patients received a TKI as first-line therapy compared to 33% of Black patients. At data cutoff, there were no differences in the number of patients still taking a TKI based on gender (p=0.616), race (p=0.665), or ethnicity (p=0.465), although 46% of Hispanic patients were still on treatment compared to 35% of non-Hispanic patients. PFS on a TKI was similar for race (p=0.352) and gender (p=0.258), however Hispanic patients with an actionable mutation had a significantly longer PFS on a TKI than non-Hispanic patients (p=0.019), but not after controlling for age (p=0.116). Conclusion: This study is among the first to analyze disparities in driver mutations and response to targeted therapy in young patients with lung adenocarcinoma. No significant differences were found in TKI treatment, TKI as first-line therapy, or current TKI use by gender, race, or ethnicity. Notable trends included a greater percentage of eligible Black patients not receiving TKIs and fewer Black patients receiving TKIs as first-line therapy, although the sample of Black patients was small. Hispanic patients had a significantly longer PFS on TKIs than non-Hispanics, but not after controlling for age. Further research is needed to evaluate these trends, particularly with a larger cohort of Black patients. Citation Format: Kyle Edwards, Brandon Rose, Gilberto Lopes, Estelamari Rodriguez, Coral Olazagasti. Disparities in the presence of driver mutations and response to tyrosine kinase inhibitors in young patients with lung cancer [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A106.