Endoscopic Placement of Self-Expandable Metal Stents for Malignant Colonic Obstruction: Long-Term Outcomes and Complication Factors

Abstract

Purpose: Self-expandable metal stents (SEMS) can be used to relieve colonic obstruction with palliative or preoperative intent. We set out to investigate the long-term outcome and complication rates of stent-based therapy for malignant colonic obstruction in a large cohort. Methods: Retrospective review of all patients who underwent SEMS placement for malignant colorectal obstruction at a single institution from 1999 to 2008. Data collected included patient demographics, stricture location, stentinduced complications, time to adverse events, and need for reintervention. Results: Of 233 patients, 168 underwent SEMS placement for palliative intent and 65 SEMS were placed as a “bridge to surgery.” The technical and immediate clinical success rates were 96% and 99% in the palliative group and less in preoperative patients (95 and 98%). 41 palliative patients had complications (24.4%) including perforation (15), occlusion (15), migration (8), erosion/ulcer (3). The median patient survival time was 87 days (mean, 152 days). Median duration of stent patency was 90 days (mean, 145 days). 108 of 122 (88.5%) patients had sustained relief of obstruction from implantation until death. The long-term clinical success rate at 6 months was 77.2%. Stents placed with preoperative intent had a mean in situ time of 25.4 days (median, 5 days). Fifteen of the 65 preoperative patients had complications (23.1%) prior to operation; 94% proceeded to elective colectomy with a median time to surgery of 6 days and 60% did not receive a stoma. SEMS remained patent until surgery in 73.8%. The overall endoscopic and surgical reintervention rate of this case series was 18.5% and 16.7%, respectively. No further intervention was required for all remaining patients at a mean follow-up of 129 days (median, 34 days). Univariate analysis identified male gender, complete obstruction, stent diameter ≤ 22-mm, stricture dilation prior to SEMS insertion, and operator experience as significant risk factors (p < 0.05) for complication. Intraluminal lesions (27 vs 19%), palliative bevacizumab (anti-VEGF antibody) (35 vs 23%), and placement in the distal colon (27 vs 13%) were also associated with higher complication rates of SEMS palliation. Conclusion: Endoscopic placement of colorectal SEMS is relatively safe and effective for relief of malignant colorectal obstruction but placement carries a complication rate of nearly 25%. Patient characteristics (gender, degree of occlusion, stricture location, subsequent chemotherapy) and technical variables (stent type, stricture dilation, operator experience) appear to affect outcome of SEMS therapy. Disclosure: Dr Baron: Consultant: ConMed Speaker's Bureau; Dr Small: None Dr Coelho-Prabhu: None.