Abstract Introduction Pulmonary resection for non-small cell lung cancer can lead to significant declines in lung function, with some patients developing severe postoperative restriction that limits recovery and treatment options. This study aims to identify preoperative and perioperative factors associated with severe pulmonary function decline following lung cancer surgery. Methods We retrospectively analyzed 99 lung cancer patients who underwent lobectomy (n = 63) or sublobar resection (n = 36) between 2022 and 2023. Pulmonary function tests (PFTs), three-dimensional computed tomography (3D-CT), and dynamic chest radiography (DCR) were performed within 30 days before surgery and repeated 6-12 months postoperatively. Severe PFT reduction was defined as 20% decline in both %FVC and %FEV1. DCR data were processed using the KINOSIS workstation to quantify diaphragmatic excursion during forced breathing. Changes in pulmonary function, lung volume, and diaphragmatic motion were evaluated. Results Among the 99 patients, 53 (54%) were female. Surgical approaches included thoracotomy (n = 26), video-assisted thoracoscopic surgery (VATS; n = 30), and robot-assisted thoracic surgery (RATS; n = 43). Most patients had lung adenocarcinoma (n = 87). Pathologic staging included 0 (n = 6), IA (n = 74), IB (n = 13), II (n = 5), and IIIA (n = 1). Mean preoperative %FEV1 and %FVC were 98.3 and 102.9, respectively; postoperative values were 85.7 and 90.7. The median interval between surgery and follow-up PFTs was 8 (6-12) months. Severe PFT reduction occurred in 18 patients (18%), with a significantly higher incidence in the lobectomy group compared to the sublobar resection group (25% vs. 6%, P = 0.015). There was no significant difference in incidence based on surgical approaches. Most patients exhibited postoperative compensatory increases in contralateral lung volume and diaphragmatic motion without changes in ipsilateral motions. In contrast, patients with severe PFT reductions demonstrated impaired compensatory diaphragmatic response and a markedly decrease in ipsilateral motion. Univariable logistic regression identified lobectomy (Odds Ratio (OR): 5.8), left upper lobectomy (OR: 9.7), reduced postoperative ipsilateral diaphragmatic motion (OR: 5.8), and postoperative complication (OR: 7.9) as significant predictors of severe PFT reduction during the follow-up. Multivariable analysis revealed that left upper lobectomy (OR: 5.7) and reduced postoperative ipsilateral diaphragmatic motion (OR: 3.9) were independently associated with severe PFT reduction (Table 1). Conclusions Impaired compensatory diaphragmatic motion assessed by dynamic chest radiography was associated with severe pulmonary function decline after lung cancer surgery. Understanding diaphragmatic dynamics may improve risk stratification, support surgical decision-making, and guide interventions to preserve postoperative function. This abstract is funded by: None
Ito et al. (Fri,) studied this question.