Multivariable logistic regression analysis revealed that prior lung disease (odds ratio, [OR]: 1.63; 95% CI, 1.02-3.31, P = .037), impaired pulmonary function after treatment (OR: 2.78; 95% CI, 1.38-5.24, P < .001), lymph node metastasis (OR: 3.05; 95% CI, 1.65-6.21, P < .001), and elevated preoperative interleukin-6 levels (OR: 1.58; 95% CI, 1.36-1.83, P < .001) were high risk factors for postoperative pulmonary complications. Here, IL6 is linked to metastatic malignant neoplasm in the lymph nodes.