The results of the interaction analysis with lymph node metastasis showed that PLAU expression was a significant factor affecting all‐cause mortality only in the population with lymph node metastasis (HR = 2.908 [95%CI: 1.864, 4.536], p < 0.001), and the interaction term was also significant (p = 0.004 [PLAU × Lymph node metastasis]). Here, PLAU is linked to metastatic malignant neoplasm in the lymph nodes.