Furthermore, we observed that overexpressed CDK4 was positively associated with tumor clinical stage (I-II vs. III-IV) (p = 0.047), but not correlated with patient's age, sex, smoking, lymph node metastasis (N classification), tumor size (T classification), and distant metastasis (M classification) in NPC (Table 2). This evidence concerns the gene CDK4 and metastatic malignant neoplasm in the lymph nodes.