Endoscopic Transluminal Stent Placement for Malignant Afferent Loop Obstruction

Background: Malignant afferent loop obstruction (ALO) is rare condition and is difficult to manage. Endoscopic transluminal treatment has become easier with the advent of balloon-assisted enteroscopes with a large working channels and self-expandable metal stent (SEMS) with a 9 Fr delivery system. Methods: From July 2016 to March 2022, 22 patients with symptomatic malignant ALO who underwent endoscopic transluminal treatment (Initial cohort), of which 18 patients received endoscopic transluminal SEMS placement (SEMS cohort), were retrospectively evaluated. We evaluated outcomes of endoscopic transluminal treatment and long-term outcomes of SEMS placement for malignant ALO. Results: In the Initial cohort, technical and clinical success rates were both 95.5%. The median procedural time was 28.0 min. One case of guidewire-induced micro-perforation occurred as an early complication (4.5%). In the SEMS cohort, and no early complication was observed. Recurrent obstruction occurred in two cases (11.1%) during the follow-up period (median: 102 days). One was managed by additional SEMS placement and the other was treated conservatively. Conclusions: High technical and clinical success was achieved by endoscopic transluminal treatment with short procedural time for malignant ALO. Endoscopic SEMS placement also appears to be safe and effective, and additional SEMS placement can be considered in cases of re-obstruction.