CD44 and neoplasm: Clinicopathological variables such as gender, smoking history, age, pathological stage, tumor type, differentiation, and ALDH or CD44 single marker expression were included in Cox regression multivariate analysis for recurrence-free survival (RFS), and results showed the male gender (HR 2.89, 95% CI 1.48-5.63, p = 0.002) and advanced pathological stage (HR 1.96, 95% CI 1.50-2.56, p < 0.001) were independent prognostic factors associated with shorter RFS.