Objective: The United States Patient Protection and Affordable Care Act allocated funds for states to expand Medicaid coverage. However, several states declined expansion. We aim to determine whether Medicaid expansion is associated with healthcare coverage, cancer stage at diagnosis, treatment, and survival among patients with rhinologic cancer. Rhinologic cancer was defined to include cancer of the nasal cavity, paranasal sinus, nasopharynx, or olfactory nerve.Study design: Cohort study. Methods: Patients diagnosed with primary rhinologic malignancies between 2007 to 2016 were extracted from the National Cancer Institute Surveillance, Epidemiology, End Results (SEER) registry. Patients were grouped by diagnosis before and after 2014 (when Medicaid expansion became effective) and whether their state had expanded Medicaid. Multivariable logistic regression controlling for age, sex, race, ethnicity, and income/education was utilized to examine associations between Medicaid expansion/insurance status and stage at diagnosis, treatment, and survival. Overall and disease-specific survival were examined using Kaplan-Meier analysis.Results: Analysis included 10,164 patients. The proportion of uninsured patients decreased after 2014 (2.4%) compared to before 2014 (4.8%, P < .001). After 2014, patients in nonexpanded states were more likely to be diagnosed with advanced stage disease compared to patients in expanded states (N = 2,364; OR = 1.27, 95% CI 1.01-1.60). Being uninsured in any state was associated with advanced stage disease at diagnosis (OR = 1.75, 95% CI 1.41-2.22) and increased risk of disease-specific death (HR = 1.54, 95% CI 1.32-1.82). Survival measures were not associated with diagnosis before versus after 2014 or Medicaid expansion.Conclusions: Patients lacking insurance or residing in nonexpanded states may be more likely to present with advanced stage rhinologic cancer. Longitudinal studies should validate these findings.