Stents in the management of malignant airway obstruction.

Surgical resection is feasible in only 20% of patients with lung cancer: less than 30% of these patients survive > 5 yrs and almost 95% of them require palliative treatment. During the course of disease, 30% of lung cancers cause obstruction of the trachea and main bronchi with subsequent respiratory distress, bleeding and infection. Similar problems arise through secondary pulmonary malignancies. There are several types of central airway obstruction; this influences the modality used for their treatment. The three basic types of stenosis are endoluminal, extraluminal and a combination of both. A mainly endoluminal stenosis can be treated with various resection techniques, such as laser, electrocautery or cryotherapy; for an extraluminal compression the only option is placement of stents, which results in efficient palliation and may prolong survival. Various stent models have been developed for the treatment of inoperable airway stenoses. They consist mainly of two types: metal and silicone devices, or combinations of both (hybrid models). The choice of a specific stent depends on the nature of the airway obstruction, the endoscopist's preference and the overall costs of the procedure. The best treatment results are usually obtained using a combination of stent placement followed by tumour-specific treatment such as irradiation or chemotherapy.