Polyurethane-covered wallstents to recanalize wallstents obstructed by tumor ingrowth from malignant common bile duct obstruction

Four patients with malignant obstruction of the common bile duct had been treated with uncovered Wallstents and suffered from a reobstruction after 2-13 months (mean 5.3 months). Repeat cholangiography revealed severe stenosis of the stent lumen caused by tumor ingrowth through the mesh. A Wallstent with a self-made polyurethane-cover was inserted through the uncovered stent in these patients. The four patients were followed for 3-13 months (mean 6.3 months) until death. There was good drainage with no evidence of recurrent obstruction in all patients. We conclude that a covered Wallstent may extend patency of stented bile ducts, preventing tumor ingrowth in patients with neoplastic obstruction. Further observations are needed.