Abstract C021: Racial and socioeconomic disparities in molecular diagnostics for NSCLC patients
Authors: Tuminello Stephanie , Turner Wiley , Untalan Matthew , Flores Raja , Taioli Emaneula 
Published: September 2024

Background: Targeted therapies have substantially changed the landscape of non-small cell lung cancer (NSCLC) outcomes. These drugs work by inhibiting specific molecular pathways, such as the epidermal growth factor receptor (EGFR) tyrosine kinase, the anaplastic lymphoma kinase (ALK), KRAS, and BRAF oncogenic pathways. Approximately 30% of NSCLC patients will have tumors with eligible targetable mutations, but a molecular test must be conducted to assess eligibility to these treatments. Disparities in molecular testing could be partially responsible for the disproportionate utilization of targeted therapy across race and socioeconomic status (SES). Methods: Surveillance, Epidemiology and End Results (SEER)-Medicare linked data was queried for NSCLC patients diagnosed from 2013 (the first year that standard guidelines for molecular testing in lung cancer were available) to 2016. Patients were limited to age over 66 years at diagnosis with continuous Part A and B coverage and no Part C coverage, for 1 year prior and 90 days post-diagnosis. The primary outcome was receipt of a molecular test based on claims data. Race, defined as white, Black or other, was the primary predictor variable. Demographic and clinical characteristics of those receiving vs not receiving a molecular test were compared using χ2 tests for categorical variables and t-tests for continuous variables. We also performed multivariable logistic regression to assess the association of molecular testing with race adjusting for sex, age, marital status, Charlson comorbidity index, histology, tumor site, stage, and census-level poverty indicator. Results: There were 28,511 NSCLC patients, of which 9,639 (33.8%) received some type of molecular testing. Black patients were significantly less likely than white patients to have received a molecular test (p&lt;0.0001). Only 23.9% of Black patients underwent any molecular testing, compared to 34.6% of white patients. Patients living in census tracts with at least 10% of residents living in poverty were also less likely to receive a molecular test (p&lt;0.0001). Patients who were female (p&lt;0.0001), married (p&lt;0.0001), with fewer comorbidities (p&lt;0.0001), adenocarcinoma histology (p&lt;0.0001), tumors located in the lower lobe (p&lt;0.0001), diagnosed at a later stage (p=0.0001) were more likely to have molecular testing. After adjustment, Black patients (ORadj [odds ratio]: 0.65; 95% CI [confidence interval]: 0.59-0.72) and those living in areas with greater poverty (ORadj: 0.87; 95% CI: 0.82-0.91) were statistically significantly less likely to have received molecular testing. Conclusions: Disparities exist in comprehensive molecular diagnostics, and could explain, at least in part, the high mortality observed among Black NSCLC patients. Addressing barriers to molecular testing could increase uptake of targeted therapy treatment, decreasing disparities and improving patient outcomes.

Citation Format: Stephanie Tuminello, Wiley Turner, Matthew Untalan, Raja Flores, Emaneula Taioli. Racial and socioeconomic disparities in molecular diagnostics for NSCLC patients [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 C021.