Racial and socioeconomic disparities in survival among patients with metastatic non-small cell lung cancer

Immune checkpoint inhibitors have profoundly impacted survival among patients with metastatic non-small cell lung cancer. However, population-based studies evaluating this impact on survival by race and socioeconomic factors are lacking.

We used the Surveillance, Epidemiology, and End Results Program-Medicare database to identify patients with metastatic non-small cell lung cancer diagnosed between 2015 and 2019. The primary study outcomes were the receipt of an immune checkpoint inhibitor and overall survival. χ2 tests and logistic regression were used to identify demographic factors associated with receipt of immune checkpoint inhibitors. The Kaplan-Meier method was used to calculate 2-year overall survival rates, and log-rank tests were used to compare survival by race and ethnicity.

Of 17 134 patients, approximately 39% received an immune checkpoint inhibitor. Those diagnosed with cancer recently (in 2019); who are relatively younger (aged younger than 85 years); non-Hispanic White, non-Hispanic Asian, or Hispanic; living in high socioeconomic status or metropolitan areas; not Medicaid eligible; and with adenocarcinoma histology were more likely to receive immune checkpoint inhibitors. The 2-year overall survival rate from diagnosis was 21% for the overall population. The 2-year overall survival rate from immune checkpoint inhibitor initiation was 30%, among those who received at least 1 cycle and 11% among those who did not receive immune checkpoint inhibitors. The 2-year overall survival rates were higher among non-Hispanic White (22%) and non-Hispanic Asian (23%) patients compared with non-Hispanic Black (15%) and Hispanic (17%) patients. There was no statistically significant racial differences in survival for those who received immune checkpoint inhibitors.

Immune checkpoint inhibitor utilization rates and the resulting outcomes were inferior for certain vulnerable groups, mandating the need for strategies to improve access to care.