Disparities in systemic treatment use in advanced-stage non-small cell lung cancer by source of health insurance

Background: Management of advanced stage non-small cell lung cancer (NSCLC) has changed significantly over the past two decades with the development of numerous systemic treatments, including targeted therapies. However, a high proportion of advanced-stage patients are untreated. The role that health insurance plays in receipt of systemic treatments is unclear. Methods: Using California Cancer Registry data (2012-2014), we developed multivariable Poisson regression models to assess the independent effect of health insurance type on systemic treatment utilization among stage IV NSCLC patients. Systemic treatment information was manually abstracted from treatment text fields. Results: A total of 17,310 patients were evaluated. Patients with Medicaid/other public insurance were significantly less likely to receive any systemic treatments (risk ratio (RR)=0.78, 95% CI=0.75-0.82), bevacizumab combinations (RR=0.57, 95% CI=0.45-0.71), or tyrosine kinase inhibitors (RR=0.70, 95% CI=0.60-0.82) compared to the privately insured. Patients with Medicare or dual Medicare-Medicaid insurance were not significantly different from the privately insured in their likelihood of receiving systemic treatments. Conclusions: Substantial disparities in the use of systemic treatments for stage IV NSCLC exist by source of health insurance in California. Patients with Medicaid/other public insurance were significantly less likely to receive systemic treatments compared to their privately insured counterparts. Impact: Source of health insurance influences care received. Further research is warranted to better understand barriers to treatment that patients with Medicaid face.