Association of the Affordable Care Act's Medicaid expansion with the diagnosis and treatment of clinically localized melanoma: A National Cancer Database study

Background: The Affordable Care Act's Medicaid expansion is associated with earlier diagnosis and improved care among lower socioeconomic status populations with cancer, but its impact on melanoma is undefined.Objective: To determine the association of Medicaid expansion with stage of diagnosis and use of sentinel lymph node biopsy in nonelderly adult patients with newly diagnosed clinically localized melanoma.Methods: Quasi-experimental, difference-in-differences retrospective cohort analysis using data from the National Cancer Database from 2010 to 2017. Patients from expansion versus nonexpansion states and diagnosed before (2010-2013) versus after (2014-2017) expansion were identified.Results: Of 83,322 patients, 46.6% were female, and the median age was 55 years (interquartile range, 4960). After risk adjustment, Medicaid expansion was associated with a decrease in the diagnosis of T1b stage or higher melanoma (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.88-0.98; P = .011) and decrease in uninsured status (OR, 0.61; 95% CI, 0.52-0.72; P < .001) but was not associated with a difference in sentinel lymph node biopsy performance when indicated (OR, 1.06; 95% CI, 0.95-1.20; P = .29).Limitations: Retrospective study using a national database.Conclusion: In this study of patients with clinically localized melanoma, Medicaid expansion was associated with a decrease in the diagnosis of later T-stage tumors.