Editorial commentAirway stenting for benign tracheal stenosis: what is really behind the choice of the stent?

The study, from Charokopos et al. [1], regarding metallic stenting in benign tracheal stenosis rises some comments. It is always important to recall that airway stenting is indicated as palliation, irrespective of the underlying etiology. Palliation means that it should be considered only after all medical or surgical options have been exhausted. Thus, stenting can be considered as a primary treatment in some cases either as a bridge towards other managements or with a curative intent. ‘A stent is a foreign body and nobody is perfect,’ so after placement, one should expect and manage stent-related complications even several times in some patients. In malignancy, the word ‘palliation’ is particularly relevant, as most of the indications rely on palliative care and, the patients unfortunately die before stent-related complications. However, in benign indications, the choice of the stent is essential. Traditionally, airway stents are divided into two categories, the silicone stents, with the Dumon stent being the gold standard, and the self-expandable metallic stents (SEMS) with the Ultraflex® (Boston Scietntific, Galway, Ireland) as the reference. Both types of stents have their complications. Migration is the main complication for silicone stents, while re-stenosis and rupture are problematic for SEMS. In benign tracheal stenosis, recent articles on SEMS-related complications [2,3] prompted the Food and Drug Administration (FDA), in 2005, to publish recommendations on their use (http://www.fda.gov/cdrh/safety/072905-tracheal.html). It was stated that one should use metallic tracheal stents in patients with benign airway disorders only after thoroughly exploring all other treatment options (such as tracheal surgical procedures or placement of silicone stents). Using metallic tracheal stents as a bridge to other therapies is not recommended, because removal of the metallic stent can result in serious complications. If a metallic tracheal stent is the only option for a patient, insertion should be done by a physician trained or experienced in metallic tracheal stent procedures. If removal is necessary, the procedure should be performed by a physician trained or experienced in removing metallic tracheal stents [4]. So, why some authors continue to prefer SEMS than silicone stenting? Silicone stents are cheaper, easier to remove, do not worsen the primary stenosis and, have shown, in a recent article [5] focusing on benign tracheal stenoses, that, after 18 months of placement, no recurrence in about 70% of cases, 1 year after removal. What is really behind the choice of an SEMS? The main answer relies upon the skills in rigid bronchoscopy. SEMS placement does not need rigid bronchoscopy, while silicone stent placement does. Most of the experts and international guidelines insist on the necessary skills in rigid bronchoscopy for physicians willing to practice interventional bronchoscopy. Stent placement and removal using rigid bronchoscopy is safer and quicker, irrespective of the type of stent. The new all covered SEMS are right now under evaluation in benign indications. Their theoretical advantage is based on the absence of metallic wire directly in contact with the mucosa, avoiding restenosis and allowing easier removal. This could be the future for SEMS but has to be demonstrated.