Post-pneumonectomy-like syndrome as a result of unilateral upper-lung field pulmonary fibrosis after lung cancer surgery: a case report.

Post-pneumonectomy syndrome is a rare complication following pneumonectomy, characterized as significant mediastinal shift and rotation toward the operated side, resulting in stenosis of trachea and bronchi. We report the case of a 60-year-old woman who underwent right lower lobectomy for lung adenocarcinoma in 2017. She subsequently developed unilateral upper-lung field pulmonary fibrosis (upper-PF) in the operated side, radiologically consistent with pleuroparenchymal fibroelastosis, as a late surgical complication. By 2025, the resulting mediastinal right shift due to upper-PF caused the descending aorta to severely compress the left main bronchus, leading to acute hypercapnic respiratory failure. While typically recognized as post-pneumonectomy syndrome, this condition is extremely rare following lobectomy. This case demonstrates that unilateral upper-PF development can induce a post-pneumonectomy-like syndrome, even in patients who have not undergone a pneumonectomy.