BACKGROUND: A high incidence of migration with covered metal stents has been reported in malignant gastric outlet obstruction (GOO). A newly modified, partially covered, triple-layer nitinol stent was developed that has a longer uncovered portion (5-15 mm) to prevent stent migration.OBJECTIVE: To estimate the efficacy and safety of the modified covered, triple-layer metal stent.DESIGN: Multicenter, prospective cohort study.SETTING: Three tertiary referral centers.PATIENTS: Fifty consecutive patients (26 with pancreatic carcinoma, 14 with gastric carcinoma, 9 with cholangiocarcinoma, 1 with a metastatic node) who presented with symptomatic unresectable malignant GOO between April 2007 and March 2010.INTERVENTIONS: Endoscopic placement of the modified covered, triple-layer metal stent.MAIN OUTCOME MEASUREMENTS: The primary endpoint was to improve the GOO scoring system (GOOSS) score. Secondary endpoints were success rate, patency, and complications.RESULTS: The median GOOSS score improved significantly (P < .0001) after stenting (from 0 to 3). The technical and clinical success rates were 100% and 90%, respectively. Stent occlusion by tumor overgrowth or ingrowth at the uncovered portion developed in 5 patients (10%). Asymptomatic stent migration occurred in 3 patients (6%) receiving chemotherapy at 95, 230, and 553 days after stent placement, but these patients tolerated solid food 68, 260, and 142 days after stent migration, respectively. Other complications occurred in 1 patient with insufficient expansion, cholangitis, and pancreatitis. No procedure-related deaths occurred.LIMITATIONS: A single-arm study in tertiary-care centers.CONCLUSIONS: The modified covered, triple-layer metal stent was effective and safe for managing malignant GOO and can prevent tumor ingrowth and stent migration. (CLINICAL TRIAL REGISTRATION NUMBER: UMIN000004566.).
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