In our recent study, immunohistochemical staining of p16 (Figure 10) and p53 (Figure 11) revealed positive nuclei in the columnar cells of Warthin’s tumor, suggesting that Warthin’s tumor is neoplastic, although whether Warthin’s tumor is a true neoplasm that occurs as a clonal growth or a non-neoplastic developmental malformation is still a matter of debate. This evidence concerns the gene CDKN2A and Warthin tumor.