Social determinants as pathways in disparities in oral cavity cancer stage at diagnosis: a registry-based analysis...

Racial and ethnic differences in oral cavity cancer (OCC) stage at diagnosis are substantial, but the reasons remain unclear. We assessed insurance status and social neighborhood factors as potential pathways.

Using the Texas Cancer Registry, we identified adults diagnosed with OCC between 2010 and 2020. We examined the crude and multivariable associations of race and ethnicity, insurance status, and social neighborhood factors with stage at diagnosis. We investigated the mediating effects of insurance status and neighborhood-level social factors on racial and ethnic differences in stage at diagnosis using four-way decomposition with modified Poisson regression and robust standard errors.

Among the 6,488 patients, 49.6% were diagnosed at a late stage. Compared to non-Hispanic White patients, non-Hispanic Black, Hispanic, and non-Hispanic Asian Americans, Native Hawaiians, and Pacific Islanders had 51% (Prevalence Ratio [PR]: 1.51; 95% confidence interval [95% CI]: 1.40, 1.63), 29% (PR: 1.29; 95% CI 1.22-1.37), and 17% (PR: 1.17; 95% CI 1.05-1.32) higher risks of being diagnosed at a late stage, respectively. For non-Hispanic Black patients, being uninsured, living in a vulnerable neighborhood, and living in a deprived neighborhood explained roughly 20%, 31%, and 15% of the disparity in late stage diagnosis, respectively. These pathways accounted for similar proportions of the disparity in stage at diagnosis among Hispanic patients.

Insurance status and neighborhood-level social factors may partially account for the differences in OCC stage at diagnosis between racial and ethnic groups. Identifying these pathways may help clarify and reduce these disparities.