Fibrotic airway stenosis following radiotherapy in patients with adenoid cystic carcinoma

Background and objective Radiotherapy is usually administered to the central airway in patients with unresectable adenoid cystic carcinoma (ACC). The purpose of this study was to describe the outcomes of endobronchial intervention in patients with airway stenosis following radiotherapy for ACC. Moreover, we investigated the incidence and contributing factors for airway stenosis following radiotherapy for ACC. Methods Forty-seven patients with ACC, who underwent radiotherapy of the tracheobronchial tree from January 1995 to December 2011, were reviewed retrospectively. Fibrotic airway stenoses were diagnosed using three-dimensional computed tomography, flexible bronchoscopy or both. Results Eleven (23%) of the 47 patients with ACC suffered fibrotic airway stenosis following radiotherapy and received bronchoscopic intervention. The median interval from radiotherapy to diagnosis of fibrotic airway stenosis was 7 months. Low forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity and brachytherapy were verified as factors contributing to radiotherapy-induced airway stenosis. Bronchoscopic intervention provided both symptomatic relief and improvement of lung function, and no procedure-related death or major complication was observed. Insertion of a straight silicone stent was required in 10 patients (91%), and 4 (36%) eventually received Y-shaped silicone stents. The stents, once implanted, could not be removed in any of the patients; stents were well-tolerated for a prolonged period in all patients. Conclusions Fibrotic airway stenosis following radiotherapy in patients with ACC is often found. Bronchoscopic intervention, including silicone airway stenting, was a safe and useful method for treating radiotherapy-induced fibrotic airway stenosis in patients with ACC.