OBJECTIVES : Racial minorities in the United States have inferior cancer outcomes. For patients with cancer, next generation sequencing (NGS) informs treatment decisions; while NGS use is increasing, it is unclear whether uptake disparities exist. This study investigated changes in racial inequity in NGS testing of cancer patients following the 2014-onwards Medicaid coverage expansion ushered by the Patient Protection and Affordable Care Act (ACA) passage, comparing states with (36/50) and without expanded coverage status.

METHODS : Real-world patients with one of 10 cancer types and ≥2 documented visits from 1/1/2011 or 1/1/2013, depending on disease type, through 12/31/2017 in the Flatiron Health EHR-derived database were included in this exploratory retrospective study. Racial inequity was defined as the absolute percent difference in diagnosis-indexed NGS testing rates for black or African-American and white patients diagnosed in the time period. We compared the absolute percent difference in the pre-period (2011-2013) to the post-period (2014-2016) and to 2017 stratified by state Medicaid expansion status. Analyses were not adjusted for other covariates and potential confounders.

RESULTS : We identified a cohort of 6,220 patients with abstraction-confirmed NGS testing (total N=49,915). Racial inequity in NGS testing use was observed in the pre-period (N=1,232) in Medicaid expansion and non-expansion states (-3.7% and -2.6% respectively). In the post-period (N=3,659), inequity dropped in expansion states (-1.6%) and grew in non-expansion states (-3.1%). Racial inequity in non-expansion states peaked in 2017 (16.9% vs 11.4%; Diff=-5.5%; N=637) while the racial inequity gap closed in expansion states in 2017 (17.6% vs 18.6%; Diff=1.0%; N=692).

CONCLUSIONS : This hypothesis-generating study suggests Medicaid expansion may be associated with a reduction in racial inequity of NGS testing in cancer patients. Further research is needed to determine drivers and significance of NGS testing disparities.