We found that the high level of REEP6 was not related to OS (Table S1) but related to poor DFS in oral cancer patients having poor cell differentiation (p = 0.035, Figure 1D; crude hazard ratios = 1.80, 95% confidence interval (CI) = 1.04–3.14, p = 0.038, Table 2). This evidence concerns the gene REEP6 and lip and oral cavity carcinoma.