Statistical analysis

The chi-squared test, Fisher exact test, Student t test, analysis of variance (ANOVA), Mann–Whitney U test, or Kruskal–Wallis one-way ANOVA was used to evaluate the correlation of C6orf141 expression with different oral tissues or clinicopathological parameters. Clinicopathological outcome is usually defined as the time from initial diagnosis or surgery to a specific event of interest. Disease-specific survival (DSS) was measured from the time of the initial resection of the primary tumor to the date of the cancer-specific death or last follow-up. Cumulative survival curves were estimated using the Kaplan–Meier method, and comparisons between the survival curves were conducted using the log-rank test. A Cox proportional hazards model was used to determine independent predictors of survival using factors that were deemed significant in the univariate analysis as covariates. A P value of <0.05 was considered statistically significant.