[en] 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.

[en] Purpose: To compare the effectiveness of various means of stenting in patients with biliary obstruction caused by pancreatic cancer in a retrospective analysis. Methods: Sixty-two patients with biliary obstruction due to unresectable pancreatic cancer underwent biliary stenting. On the basis of the findings obtained by percutaneous transhepatic cholangiography(10 patients) and endoscopic retrograde cholangiography (52 patients),the site of obstruction was distal to the hilar confluence,predominantly especially in the middle to lower third of the common bile duct. Polyurethane-covered Wallstents (9 mm in diameter) we reinserted in 13 patients, while uncovered Wallstents (10 mm in diameter)were used in 10 patients and plastic stents (10 Fr and 12 Fr) were used in 39 patients. Results: Stenting was successful in 34 patients (87.2%) treated with plastic stents and in 22 patients(95.7%) treated with Wallstents. Effective biliary drainage was achieved in 32 out of 34 patients (94.1%) treated with plastic stents and in 21 out of 22 patients (95.5%) treated with Wallstents. The cumulative patency rate was significantly higher for the uncovered and covered Wallstents compared to plastic stents, but was not significantly higher for covered than for uncovered Wallstents. Stentocclusion occurred in 23 patients (70%; all by clogging) from the plastic stent group, in two patients (22%; by tumor ingrowth) from the uncovered Wallstent group, and in one patient (9%; by clogging) from the covered Wallstent group. The survival rate showed no significant difference among the three stent groups. Conclusion: The Wallstent is effective for long-term palliation in patients with obstruction caused by pancreatic cancer invading the middle to lower part of the common bile duct. The covered Wallstent can prevent tumor ingrowth, a problem with the uncovered Wallstent. However, it may be necessary to take measures to prevent the migration or clogging of covered Wallstents

[en] A 71-year-old man developed pyloric stenosis caused by gastric cancer. Vomiting and nausea resolved after the insertion of an uncovered Ultraflex stent (length 10 cm, inner diameter 18u23 mm) through a 7-cm-long stenosis, and the patient was able to eat a soft diet. After 6 weeks, stent occlusion occurred due to tumor ingrowth and accumulation of food residue. Endoscopic observation showed a very narrow residual lumen. A covered Ultraflex stent (length 10 cm, inner diameter 18u23 mm) was inserted through the first stent and expanded to its maximum diameter over the next 2 days. The patient's vomiting and nausea improved rapidly. He died 6 months after the second stenting procedure, from metastatic tumor spread, having remained free of nausea and vomiting. In this case, a covered metallic stent prevented tumor ingrowth and maintained gastrointestinal patency