Use of studded Polyflex stents in patients with neoplastic obstructions of the central airways

The Polyflex is a commercially available silastic airway stent with proven efficacy. Due to a smooth outer surface its anchorage in the airway wall is superficial which may lead to stent migration.

To study the performance of an newer version of the Polyflex stent with a studded outer surface, which should improve anchorage.

In a 5-centre international study the new stent was prospectively tested in symptomatic patients with neoplastic central airway stenosis of more that 50% of normal diameter. Insertion technique, efficacy of stent placement and stent-related complications were recorded before, 1 month and 3 months post stent placement.

Under general anaesthesia and rigid bronchoscopy 27 stents were inserted in 26 patients, mean age: 62 years (range: 37-83), 16 men. Diagnoses were 18 bronchogenic carcinoma, 4 oesophageal carcinoma, 2 metastases, 1 tracheal carcinoma, and 1 schwannoma. The stents were inserted in the following locations: 10 right main bronchus, 8 left main bronchus, 7 trachea, and 2 tracheo-bronchial. There was significant improvement in all functional parameters assessed from before (A), to 1 month (B) and 3 months (C) after stent placement. The measured values (mean +/- SD) were for the WHO scale: A: 2.7 (0.8), B: 1.5 (0.9), C: 1.6 (1.0); for the Karnofsky scale: A: 44 (19), B: 72 (18), C: 71 (21); for the Dyspnoea Index: A: 3.3 (0.7), B: 1.5 (0.8), C: 1.9 (1.2); for FEV(1): A: 1.2 (0.5), B: 1.9 (0.6), C: 1.5 (0.5), and for FVC: A: 2.1 (0.7), B: 2.8 (0.7), C: 2.5 (1.0). Stent-related complications were 4 reversible stent obstructions by secretions, 1 migration. The observation period was mean 4.3 months (range 2 days to 23 months).

The studded Polyflex showed excellent efficacy, was very well tolerated, and had a very low migration rate. It presents an improvement over the older smooth model and can be considered a true alternative to the most widely used silastic stent, the Dumon stent.