Self-reported race and ethnicity in relation to oral potentially malignant disorders and oral cancer

To investigate the association between self-reported race and ethnicity with oral potentially malignant disorders and oral cancer, considering environmental and genetic influences.

This was a case-control study including clinical information and DNA samples from 792 subjects from the University of Pittsburgh dental clinics. The cases were 264 subjects diagnosed with oral potential malignant disorders or oral squamous cell carcinoma. Controls were matched by sex and age in a 1:2 ratio. χ² tests detected differences between groups regarding ethnicity, race, and covariates. A Post-hoc test with Bonferroni and Holm corrections accounted for multiple comparisons between groups. A standard χ² residual test was used to investigate which ethnicity category contributed most to the association. Multiple logistic regression models were used to obtain the unadjusted and adjusted odds ratios (ORs) and to detect the association between single-nucleotide variants and outcomes, stratified by ethnicity and race.

The risk of having the outcomes was 78% greater in those patients who self-reported as African American (OR, 1.78; P = .002; 95% confidence interval, 1.225-2.592). Minor allele G (rs9879992-GSK3B) increased the risk for the outcomes in patients who self-reported as African American (OR, 1.85; P = .002; 95% confidence interval, 1.236-2.772).

Self-reported race and ethnicity were associated with oral potential malignant disorder/oral cancer. Future studies using ancestry informative markers can confirm these findings.