The positive rate of MST4 expression was also significantly higher among patients experiencing lymph node metastasis (96.2% n=63/65) compared with patients negative for lymph node metastasis (81.6% n=31/38) (P=0.012), indicating that MST4 may play an important role in breast cancer metastasis. The gene discussed is STK26; the disease is metastatic malignant neoplasm in the lymph nodes.