S0911 Self-Expanding Metal Stents for Palliation of Malignant Gastric Outlet Obstruction: Does Cover Material Matter? A Meta-Analysis

Abstract

INTRODUCTION: Knowledge regarding the optimal cover material for fully or partially covered self-expanding metal stents (CSEMS) deployed for palliation of malignant gastric outlet obstruction (MGOO) is lacking. METHODS: A comprehensive literature search was performed of Medline (Ovid) and Embase from inception-July 2019. All studies were screened by two authors to identify studies reporting the safety and efficacy of CSEMS for palliation of MGOO with information on CSEMS cover material. A logistic-normal random-effects model was applied while pooling data to account for effect sizes close or equal to zero and one. Pooled data was reported as proportions with 95% confidence interval (CI). RESULTS: Screening of 3553 articles yielded 13 studies (5 on silicone CSEMS, 8 on Polytetrafluoroethylene (PTFE)-CSEMS) enrolling 646 patients (484 with PTFE-CSEMS, 162 with silicone CSEMS). Technical success rate was 99% (95–100%) and 100% (98%–100%) for silicone CSEMS and PTFE-CSEMS. Clinical success of PTFE-CSEMS was 94% (86–97%) which was higher than the clinical success of silicone CSEMS (90%; 82–94%). The pooled adverse event rate for silicone CSEMS and PTFE-CSEMS was 26% (20–32%) and 62% (32–85%), respectively. Stent migration occurred in 17% (11–24%) and 23% (10–36%) of PTFE-CSEMS and silicone CSEMS. Stent collapse/fracture rate was 4% (0–8%) and 5% (1–9%) for PTFE-CSEMS and silicone CSEMS. Tumor ingrowth occurred in 2% (0–4%) and 31% (24–39%) of PTFE-CSEMS and silicone CSEMS. Tumor overgrowth occurred in 4% (1–7%) and 5% (0–9%) of PTFE-CSEMS and silicone CSEMS. Luminal perforation rate was 2% (1–4%) and 1% (0–4%) with PTFE-CSEMS and Silicone CSEMS. Post-procedural bleeding rate was 2% (0–5%) and 1% (0–4%) with PTFE-CSEMS and Silicone CSEMS. Endoscopic reintervention rate was 24% (10–37%) and 29% (0–59%) with PTFE-CSEMS and silicone CSEMS. Surgical intervention rate was 2% (0–5%) and 1% (0–4%) for PTFE-CSEMS and silicone CSEMS. CONCLUSION: A trend towards higher rate of adverse events, particularly stent migration and tumor ingrowth was observed with Silicone CSEMS use upon indirect comparison with PTFE-CSEMS; this may translate into a higher reintervention rate. Further well-designed studies are needed to validate and build upon our findings. The standard of care for MGOO in the US remains uncovered SEMS; we anticipate our findings can aide investigators as well as policy makers when considering expanded access to CSEMS in the US.Table and Figure 1.: Safety and Efficacy Outcomes of Covered Self-Expanding Metal Stent Insertion for the Palliation of Malignant Gastric Outlet Obstruction Stratified by Cover Type