Impact of race on outcomes of advanced stage non-small cell lung cancer in an equal access setting

Abstract

Background: Impact of race in advanced stage non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs) is conflicting. Few studies have significant representation of Black patients, and these studies lack detail on access to care, such as time to treatment initiation (TTI). Our study sought to examine racial disparities in TTI, overall survival (OS), and progression-free survival (PFS) using a population that was almost equally Black and White. Methods: This was an IRB approved retrospective cohort study of stage IV NSCLC patients > 18 years receiving immunotherapy at our center between 2014 and 2021. Associations between demographic characteristics and median values were examined using Chi-square tests. Kaplan-Meier curves and multivariate Cox proportional hazards model determined predictors of OS and PFS. Analyses were done using IBM PSAW (SPSS v.28) with p-value < 0.05 indicating significance. Results: Of 194 patients who met the eligibility criteria, 42.3% were Black (n=82). On Kaplan-Meier analysis, no difference was observed between White and Black patients with respect to median PFS (6.30 versus 7.90 months; log-rank p=0.977) and OS (9.50 versus 11.77 months; log-rank p=0.457). On multivariate analysis, there was no difference in PFS (HR: 0.98; 95% CI: 0.68,1.43; p=0.928) or OS (HR: 1.01; 95% CI: 0.67,1.51; p=0.969) when controlling for race, sex, age at diagnosis, pack years, marital status, insurance type, histology, and Charlson Comorbidity Index (CCI). There was no difference in treatment selection between White and Black patients (p=0.184; chi-square), nor was there a difference in median time to overall treatment initiation (28.00 days versus 22.00 days; p=0.159). A difference was evident for immunotherapy initiation (34.00 versus 27.00 days; p=0.042) between White and Black patients respectively. Conclusion: Although race was expected to permeate patient outcomes, OS and PFS did not differ between Black and White patients. The significantly shorter time to immunotherapy treatment for Black patients is an unexpected finding. In our study, we highlighted that equitable access reduces disparities, bridges gaps in care, and improves patient outcomes, regardless of race. Further studies with equitable representation of diverse racial groups are warranted to better understand how race impacts cancer outcomes.