Covered vs. uncovered self-expandable metal stents for palliation of malignant afferent loop obstruction: a multicenter study

Abstract

Background and aims Endoscopic stent placement is a palliative therapy for malignant digestive tract obstruction. However, its use for malignant afferent loop obstruction (mALO) has not been adequately investigated. Methods From March 2009 to December 2020, 137 patients with mALO who underwent endoscopic stent placement at three tertiary care centers were retrospectively enrolled. The primary aim of this study was to compare stent dysfunction (SD) between the covered self-expandable metal stent (CSEMS) and uncovered self-expandable metal stent (UCSEMS) groups, with subgroup analysis among patients with extrinsic and intrinsic tumors separately. Results Twenty-three patients developed SD in the CSEMS group and 29 patients in the UCSEMS group (log-rank p = .974). The primary contributors to SD included a higher risk of stent migration in the CSEMS group and stent ingrowth in the UCSEMS group (p = .003; p < .001). Among patients with extrinsic tumors, the CSEMS group showed a significantly higher probability of overall SD (p = .008) and stent migration (p = .001) with a shorter time to SD (log-rank p = .006) than the UCSEMS group. Among patients with intrinsic tumors, the CSEMS group showed a significantly lower incidence of overall SD (p < .001) and stent ingrowth (p < .001) with a longer time to SD (log-rank p = .011) than the UCSEMS group. Conclusions Our results showed no significant difference in SD between the CSEMS and UCSEMS groups for palliation of mALO. Furthermore, subgroup analysis suggested using CSEMSs for patients with intrinsic tumors, and UCSEMSs for those with extrinsic tumors.