Surgical Interval as a Risk Factor for Postoperative Complications After Repeated Lung Cancer Resection: A Retrospective Cohort Study.

BACKGROUND: With improved survival after initial surgery, repeated pulmonary resections are increasingly performed. However, the clinical effect of the interval between operations remains unclear. METHODS: This study retrospectively analyzed data from patients who underwent only contralateral repeated pulmonary resection for lung cancer at a single institution between 2002 and 2024, assessing 30-day postoperative complications. Surgical interval was categorized as ≤3 months and >3 months. Multivariable logistic regression was employed to identify risk factors for morbidity. RESULTS: The final cohort comprised 246 contralateral second resections in 123 patients. The mean surgical interval was 40.2 months (median, 27 months). Approximately 40% of second resections occurred within 12 months of the first, half of which were within 3 months. Postoperative complications developed in 25 (20.3%; n = 25/123) patients who were frequently male, had a lower body mass index, and more commonly underwent anatomic resection. Multivariable analysis revealed age (odds ratio [OR], 1.15; 95% CI, 1.04-1.28), male sex (OR, 0.09; 95% CI, 0.02-0.40), anatomic resection (OR, 11.0; 95% CI, 2.08-58.3), and ≤3-month surgical interval (OR, 3.36; 95% CI, 1.01-11.3) as independently associated with postoperative complications. The overall morbidity rate was significantly higher in patients with a ≤3-month interval compared with longer intervals (36.0% [n = 9/25] vs 16.3% [n = 16/98]; P = .029). CONCLUSIONS: Contralateral repeated pulmonary resection is feasible, but a ≤3-month surgical interval is associated with greater postoperative morbidity. The surgical interval should be considered an important factor in operative planning.