CDKN2A and metastatic malignant neoplasm in the lymph nodes: Smoking interacted significantly with four factors—stages, UGT2B17-deletion, p16 (+), and the combination of UGT2B17-deletions and p16 (+)—to induce TP53-mutations, but not with age (P = 0.55), gender (P = 0.22), drinking status (P = 0.90), primary tumor sites (P = 0.09), tumor grades (P = 0.30), the number of lymph node metastasis (P = 0.51) or CDKN2A-SCNAs (P = 0.08).