Drug-eluting non-vascular stents for localised drug targeting in obstructive gastrointestinal cancers

Stents are currently the primary choice for the treatment of both vascular and non-vascular occlusions and/or stenosis. Despite the proven history of clinical safety and efficacy, the benefit of traditional vascular or non-vascular stenting is often limited by in-stent restenosis, resulting in failure of existing stent or reintervention by use of another stent. Coronary drug-eluting stents (DESs) significantly reduce restenosis of vascular stents and have revolutionised the percutaneous coronary intervention (PCI) treatment in coronary stenting patients. Following the similar concept of coronary DESs, non-vascular DESs are being investigated to reduce non-vascular restenosis caused by tumour growth, enhance stenting functions, and increase their effectiveness in the treatment of obstructive gastrointestinal (GI) cancers. This article summarises and updates the outcomes of preclinical and clinical studies on non-vascular DESs for localised management of malignant GI obstructions with emphasis on fabrication techniques and regulatory requirements relevant to development and marketing approval.