Efficacy of multi-hole self-expandable metal stent compared to fully covered and uncovered self-expandable metal stents in patients with unresectable malignant distal biliary obstruction: a propensity analysis.

Abstract

Self-expandable metal stent (SEMS) insertion is the standard palliative treatment for unresectable malignant extrahepatic biliary obstruction (MBO). Drawbacks of conventional fully covered SEMS (FCSEMS) and uncovered SEMS (USEMS) include stent migration and tumor ingrowth, respectively. This study aimed to compare stent patency in MBO with the newly design multi-hole SEMS (MHSEMS), which has multiple small side holes in the stent membrane, with conventional FCSEMS and UCSEMS. This retrospective study using a propensity score matching design and stent patency times of 40 patients with MHSEMS was compared to 40 and 34 patients with FCSEMS and UCSEMS during the same period, respectively. Secondary outcomes were procedure-related adverse events, clinical success rate, time to recurrent biliary obstruction (RBO), and etiology of RBO. RBO was compared using Kaplan-Meier analysis. Baseline characteristics after matching were comparable among the 3 groups. RBO rates were 21%, 37%, and 55% for MHSEMS, FCSEMS, and UCSEMS, respectively (p = 0.014), at a mean time of 479, 353, and 306days, respectively (MHSEMS vs UCSEMS, p = 0.002). Rate of tumor ingrowth was highest in the UCSEMS group (42.4% vs 13.2% in MHSEMS; p = 0.005 and vs 0% in FCSEMS; p < 0.001). Stent migration rate was highest in the FCSEMS group at 15.8% vs 2.6% in MHSEMS (p = 0.047) and 0% in UCSEMS (p = 0.005). MHSEMS provided the longest stent patency time with lowest RBO rate compared to conventional SEMS by showing a lower stent migration rate than FCSEMS and a lower tumor ingrowth rate than UCSEMS.