Lobe-Specific Variability in Postoperative Pulmonary Function in Lung Cancer Patients: A Longitudinal Analysis and Comparison With Traditional Predictive Models

Background and Objective: Lobectomy is the primary treatment for early-stage non-small cell lung cancer. However, pulmonary function declines postoperatively, presenting a significant challenge. This study investigated pulmonary function following lobectomy and compared these changes with predicted lung function based on the traditional segmental method, focusing on resected lobe-specific variability. Methods: This prospective cohort study included 419 patients who underwent lobectomies for NSCLC. Pulmonary function tests measuring forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), and diffusion capacity for carbon monoxide (DLCO) were conducted preoperatively and at 1, 3, 6, and 12 months postoperatively. We compared the observed pulmonary function values to the predicted postoperative (PPO) values based on the traditional segmental method and analysed lobe-specific differences using mixed-effects models. Results: Left upper and right lower lobectomies demonstrated observed pulmonary function values similar to their PPOs as early as 2 weeks postoperatively. However, the other lobes declined significantly, with an approximately 25% reduction in FVC, FEV1, and DLCO, regardless of the number of segments in the lobe. Three months postoperatively, observed pulmonary function values exceeded PPO values across all lobes. Surgical approach (open vs. video-assisted thoracoscopic surgery), right upper lobectomy in the reference to right lower lobectomy, and postoperative decreased physical activity were significant factors related to the non-recovery of lung function to their PPOs at 6 months after surgery. Conclusion: Postoperative pulmonary function recovery varied significantly by resected lobe, with most lobes showing better recovery than predicted postoperative values. Accurate outcome prediction requires accounting for lobe-specific characteristics and compensatory mechanisms. (Figure presented.).