Palliation in Patients with Malignant Gastric Outlet Obstruction with the Newly Designed WallFlex Duodenal Stent: First Data of a Multicenter, Prospective Trial

Abstract

Background: Self-expandable metal stents (SEMS) are being increasingly used to palliate malignant stenoses of the gastric outlet and proximal small bowel. The reported short-term (30-day) clinical success and complication rates of this new enteral stent made of nitinol (Boston Scientific WallFlex™ Duodenal Stent) were excellent. The purpose of our study was to evaluate technical and clinical success of this device as well as complications in the medium-term follow-up. Methods: To evaluate efficacy of the stent, associated to obstruction relief and the ability to have satisfactory quality of diet, considering satisfactory diet as soft solids or normal diet. Gastric outlet obstruction symptoms were graded according to a well defined scoring system (GOOSS). From 11/16/06 until 11/06/07 54 prospective patients were enrolled into the study in 8 german referral centers. There were 31 female and 23 male patients, median age 72.6 years (48-94). Data were collected from charts and endoscopy procedure reports. The follow-ups where done at 15 days, 1 month, 3 months, 6 months, 9 months by clinical visits or personal interview by phone. Results: Primary stent placement was successful in 51 patients (technical success, 94.4%) and a total of 56 stents were placed. Two patients received a second stent. In 1 patient the stent migrated during the deployment and in another patient the stent did not cover the stricture completely. The short term (within 30 days) clinical success rate was 98% (53/54) with 55% (29/53) patients able to tolerate normal oral intake without obstructive symptoms. Median follow-up was 4.1 months. The mean survival was 71.5 days (range 2-216) and 30 patients died in the follow-up due to tumor progression. No death was stent related. 3-months-follow-up data was available in 16 patients and all were able to eat: 9 were able to take normal diet (56.3%); 6 soft diet (37.5%), and 1 liquid diet (6.2%). Minor complications occurred in 10 patients (5.4%): pain (7), migration (1), stent obstruction (1) and melena (1). Conclusion: Placement of this newly designed self-expandable WallFlex duodenal stent is clinically effective in patients with unresectable gastric outlet or duodenal obstruction. Also in the long run this device appears to be effective and relatively safe.