NSCLC patients with lymph node metastases had higher serum IL-10 levels than NSCLC patients without lymph node metastases (18.03 (10.56–24.22) pg/ml vs. 15.92 (11.32–22.17) pg/ml; respectively, P < 0.05). Here, IL10 is linked to metastatic malignant neoplasm in the lymph nodes.