CT-based emphysema score is associated with prolonged air leak after lung resection: a retrospective cohort study

Background: Prolonged air leak (PAL) is a common complication after lung resection for non-small cell lung cancer (NSCLC). This retrospective cohort study investigates the association between computed tomography (CT)-based emphysema score and PAL in patients undergoing lung resection for NSCLC. Methods: Patients who underwent lung resection for pathological stage I–IIIA NSCLC at a single institution [2010–2021] were identified. Exclusion criteria included neoadjuvant therapy, missing preoperative chest CT, pneumonectomy, or bilobectomy. Chest CT-based emphysema score was defined as the percentage of emphysematous lung [density <−950 Hounsfield units (HU)] in the ipsilateral lung. PALs were defined as those lasting more than 5 days. Univariable and multivariable logistic regression analyses were conducted. Results: Among 550 patients, 58% (321/550) were female and 77% (425/550) were White. Approximately 67% (366/550) underwent a lobectomy, of which 67% (246/366) were upper lobe resections. Additionally, 79% (432/550) of patients underwent minimally-invasive surgery and 9% (48/550) developed a PAL. On multivariable analysis, after adjusting for age, gender, body mass index (BMI), surgical approach, lobe operated upon, procedure performed, pack-years and tumor size, percentage of emphysema [odds ratio (OR) =1.04; 95% confidence interval (CI): 1.01–1.07; P=0.02], lobectomy (OR =2.59; 95% CI: 1.04–6.41; P=0.040) and history of cardiothoracic surgery (OR =3.50; 95% CI: 1.53–8.03; P=0.003) were associated with PAL. We identified 16% as the optimal emphysema score cut-point for predicting PAL, with sensitivity of 38%, specificity of 76%, and accuracy of 73%. Conclusions: CT-based emphysema score is associated with PAL following lung cancer resection and may help guide intraoperative planning and patient counseling.