A Pilot Study of a Novel through-the-Scope Self-Expandable Metallic Airway Stents Delivery System in Malignant Central Airway Obstruction

Objective. Self-expandable metallic (SEM) airway stents are an important approach to malignant central airway obstruction (CAO). SEM airway stent insertions are usually performed under fluoroscopic guidance over a guide wire placed through a flexible bronchoscope often resulting in a longer procedure time and exposure to radiation. In this pilot study, we designed a novel delivery system of the through-the-scope (TTS) SEM airway stent insertion and observed its feasibility. Methods. From Jan 2015 to Sept 2016, 25 consecutive patients with inoperable malignant CAO were enrolled requiring airway stent implantation. All patients were followed up to death or at least 6 months. Results. 36 TTS stents were inserted into 25 patients using a flexible bronchoscope under general anesthesia or local anesthesia. All stents were successfully deployed directly through the working channel (2.8 mm diameter) of the flexible bronchoscope in 91.7% (33/36) of the subjects. The mMRC score and stenosis grade improved significantly after stent implantation. The common stent-related complications were secretion retention (25%, 9/36), development of granulation tissue (13.9%, 5/36), tumor in-growth (13.9%, 5/36), and hemoptysis (8.3%, 3/36). The 6-month overall survival (OS) was 44% (11/25). Conclusion. The novel TTS stent release system was an effective and safe approach in malignant central airway obstruction.