The recurrence of disease was statistically significantly associated with a number of clinicopathological variables including tumor stage (P < 0.001), histologic types (p = 0.008), SKP2 expression level (p < 0.001), serum squamous cell carcinoma (SCC) antigen level (p = 0.015) and carcinoembryonic antigen (CEA) level (p = 0.01) before treatment (Table 1). This evidence concerns the gene CEACAM5 and squamous cell carcinoma.