Resection of 4 or more pulmonary segments increases the risk of non-cancer-related mortality.

Objectives: This study retrospectively analysed the effect of the number of resected pulmonary segments on surgical outcomes of patients with non-small-cell lung cancer undergoing anatomical pulmonary resection.

Methods: We examined patients who underwent lobectomy or segmentectomy for non-small-cell lung cancer between January 2016 and June 2021. We compared the surgical outcomes between the ≤3 segment group (group A) and the ≥4 segment group (group B). Lung functions were evaluated by comparing the preoperative and 6-month postoperative periods. Comprehensive preoperative status, including osteoporosis, sarcopenia and lung function, was incorporated into the propensity score matching analysis.

Results: Propensity score matching for 420 patients yielded 310 for evaluation (1:1 matching), with a median follow-up of 57.6 months. Fifty-four patients (17.5%) died (17 from lung cancer and 37 from other diseases), and 50 patients (16.1%) experienced cancer recurrence. The 2 groups had no significant differences in surgical outcomes, including operation time, blood loss and postoperative complications. However, group B showed the worst reduction in vital capacity and forced expiratory volume in 1 s (all P < 0.05). Additionally, there were no significant differences in cancer recurrence or lung cancer mortality between the groups, although group B was significantly associated with increased deaths from other causes (P = 0.007, Gray's test; adjusted subdistribution hazard ratio 2.392; 95% confidence interval 1.170-5.167). Subgroup analyses revealed adverse effect modification in male patients regarding non-cancer-related deaths (P-value for interaction = 0.044).

Conclusions: The ≥4 segment group exhibited poorer postoperative pulmonary function and more deaths from other causes, indicating the need for careful postoperative management.