The freedom of choice

Abstract

Endoscopic stent placement is the current standard treatment for benign biliary strictures (BBS). There are two main treatment options: either the implantation of multiple plastic stents (MPS) or the implantation of selfexpandable metal stents (SEMS) (1,2). Which of the two stent implantation strategies is the better choice remains a matter of interest. Other therapies such as balloon dilatation and bouginage that are still frequently used in clinical practice provide a modest additional benefit. The most common causes of BBS include stenosis due to chronic pancreatitis (CP) or postoperative after orthotopic liver transplantation (OLT) or cholecystectomy (CCY) (3). The combination of endoscopic dilatation with sequential placement of MPS over a 1-year period shows high efficacy in resolving BBS after OLT (80-90%) as well as in patients with CP (44-92%) (1,4). However, the procedure is demanding and an average number of 4-5 endoscopic retrograde cholangiopancreatography (ERCP) is needed and causes an increased rate of complications (5). Recent studies moved the use of fully covered self-expandable metal stents (FCSEMS) into focus. FCSEMS have a low occlusion rate and a larger diameter compared to PS, which may turn out to be beneficial in the long-term treatment of BBS (6,7). However, comparative studies demonstrating a longer patency of SEMS compared to MPS are not available. In a prospective nonrandomized clinical trial the effectiveness and safety of FCSEMS for the treatment of BBS has been shown (8). Randomized clinical studies comparing FCSEMS with MPS in BBS have not been conducted before. Coté et al. present an open-label, multi-centre, randomized clinical trial comparing FCSEMS with MPS in BBS (9). The study was conducted to reveal a non-inferiority of FCSEMS versus MPS.One hundred and twelve patients (73 OLT patients, 35 CP patients, 4 CCY patients) with a symptomatic stricture of the common bile duct, located at least 2 cm below the hepatic confluence were randomized either to receive FCSEMS or MPS. Strictures had to be-in contrast to previous studies-less than 75% of the diameter of the unaffected bile duct with a minimum size of 6 mm and a maximum length of 8 mm. Diameter of FCSEMS was in addition adapted to the size of the surrounding bile duct to lower the migration rate. Successful stricture resolution was determined after a 12-month stent therapy and defined as a residual diameter of the stricture more than 75% of the duct above and below the stricture. With a resolution rate of 92.6% in the FCSEMS group against 85.4% in the MPS group (rate difference 7.2%; 95% CI, −3.0% to ∞; P<0.001), the noninferiority was proven. Furthermore, the number of ERCPs (2.14 vs. 3.24; P<0.001) and the time to resolve the stricture (181 vs. 225 days; P=0.006) was significant lower in the FCSEMS group compared to MPS group. Subgroup analysis confirmed these observations in patients after OLT and with CP without reaching statistical significance. However, the study was not adequately powered for this subgroup analys...