Interestingly, our current founding showed that higher expression of CCR9 could be linked with tumor size in lung adenocarcinoma; the positive expression rate of CCR9 (58/68, 85.3 %) in tumor tissue with lymph node metastasis was greater than that without lymph node metastasis (47/76, 61.8 %). The gene discussed is CCR9; the disease is metastatic malignant neoplasm in the lymph nodes.