Abstract B007: Racial differences in survival among veterans and nonveteran populations with stage I non-small cell lung cancer

Abstract

Abstract Purpose: Racial disparities in survival persist in patients with early-stage non-small cell lung cancer (NSCLC). Possible contributors to these disparities are stage at diagnosis, comorbidities, and socioeconomic factors. The goal of this study is to compare differences in survival between black and white patients from veteran and non-veteran populations, while accounting for treatment. Methods: Black and white men aged ≥65 years diagnosed with stage I NSCLC from 2001-2009 were identified in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database and Veterans Affairs (VA) cancer registry. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for differences between black and white patients in postoperative mortality among surgery patients, 5-year overall survival (OS), and lung cancer specific survival (LCSS). Results: There were 8,744 and 7,895 patients in the SEER and VA cohorts, respectively. Overall, black patients were less likely to be treated than white patients (74% vs 85% in SEER, p<0.0001; 69% vs 77% in VA, p<0.0001), and among treated patients, to receive surgery only (47% vs 62% in SEER, p<0.0001; 55% vs 62%, p=0.0007 in VA). OS was worse for black compared to white patients after adjustment for demographic and clinical factors (HR: 1.17, 95% CI: 1.06-1.30 in SEER; HR: 1.08, 95% CI: 1.00-1.16 in VA). However, there was no difference in OS when also adjusting for treatment (HR: 0.99, 95% CI: 0.89-1.09 in SEER; HR: 0.97, 95% CI: 0.91-1.05 in VA). For LCSS, the HRs for black vs. white patients were 1.21 (95% CI 1.07-1.37) in SEER and 1.06 (95% CI 0.96-1.17) in VA, when adjusting for demographic and clinical factors. LCSS HRs were not statistically significant in either cohort when also adjusting for treatment (HR: 0.99, 95% CI: 0.87-1.12 in SEER; HR: 0.93, 95% CI: 0.85-1.02 in VA). Similar results were obtained when analyses were restricted to patients receiving treatment, accounting for treatment modality. Among patients receiving surgery only, adjusted OS was similar across races (HR: 1.11, 95% CI: 0.91-1.36 in SEER; HR: 1.08, 95% CI: 0.95-1.23 in VA). There was no significant difference in postoperative 30-day survival in black vs. white patients (HR: 1.57, 95% CI: 0.99-2.49 in SEER; HR: 1.10, 95% CI: 0.71-1.70 in VA), nor in postoperative 90 day survival (HR: 1.28, 95% CI: 0.87-1.89 in SEER; HR: 0.90, 95% CI: 0.63-1.29 in VA). Conclusion: Among older stage I NSCLC patients, no significant racial differences in overall or lung cancer survival were detected in VA or SEER cohorts when accounting for treatment, despite observing racial differences in receipt of treatment in both populations. This suggests that survival disparities are significantly reduced when black and white patients receive similar treatment, even in populations covered by different health care systems. Effort to facilitate stage appropriate treatment in minority patients should be initiated. Citation Format: Naomi D. Alpert, Christina D. Williams, Thomas Redding, A. Jasmine Bullard, Raja Flores, Emanuela Taioli. Racial differences in survival among veterans and nonveteran populations with stage I non-small cell lung cancer [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr B007.