Non-superiority of lumen-apposing metal stents over plastic stents for drainage of walled-off necrosis in a randomised trial

Abstract

ObjectiveAlthough lumen-apposing metal stents (LAMS) are increasingly used for drainage of walled-off necrosis (WON), their advantage over plastic stents is unclear. We compared efficacy of LAMS and plastic stents for WON drainage.DesignPatients with WON were randomised to endoscopic ultrasound-guided drainage using LAMS or plastic stents. Primary outcome was comparing total number of procedures to achieve treatment success defined as symptom relief in conjunction with WON resolution on CT at 6 months. Secondary outcomes were treatment success, procedure duration, clinical/stent-related adverse events, readmissions, length of hospital stay (LOS) and costs.Results60 patients underwent LAMS (n=31) or plastic stent (n=29) placement. There was no significant difference in total number of procedures performed (median 2 (range 2–7) LAMS vs 3 (range 2–7) plastic, p=0.192), treatment success, clinical adverse events, readmissions, LOS and overall treatment costs between cohorts. Although procedure duration was shorter (15 vs 40 min, p<0.001), stent-related adverse events (32.3% vs 6.9%, p=0.01) and procedure costs (US$12 155 vs US$6609, p<0.001) were higher with LAMS. Significant stent-related adverse events were observed ≥3 weeks postintervention in LAMS cohort. Interim audit resulted in protocol amendment where CT scan was obtained at 3 weeks postintervention followed by LAMS removal if WON had resolved. After protocol amendment, there was no significant difference in adverse events between cohorts.ConclusionExcept for procedure duration, there was no significant difference in treatment outcomes between LAMS and plastic stents. To minimise adverse events with LAMS, patients should undergo follow-up imaging and stent removal at 3 weeks if WON has resolved.Trial registration numberNCT02685865.

Comparison of three different stents for endoscopic ultrasound‐guided drainage of pancreatic fluid collection: A large retrospective study

“…Although it is not statistically significant, bleeding in PS group seemed to be self‐limited because all the four severe bleeding (required embolization, surgery, or death) occurred in metal stent (LAMS and FCSEMS) group. It was consistent with previous reports and attracted increasing attention . Bang et al .…”

“…Although LMAS was widely perceived superior to FCSEMS and PS, our study and some other latest studies revealed that efficacy and safety of LAMS might not be substantially improved, as suggested by the treatment outcomes compared with PS and FCSEMS . One possible reason was that metal stents with larger diameter allow the bidirectional movement of contents between the gastrointestinal tract and the cavity.…”

EUS-guided treatment of WON using lumen-apposing metal stents: protocol standardisation based on the occurrence of natural healing processes

“…Moreover, Stecher et al 5 described an increased risk of bleeding even with another type of LAMS, the NAGI stent. Finally, Zhu and colleagues6 observed AEs similar to those of Bang et al ,1 such as delayed bleeding, buried stent syndrome and biliary stricture in 50% of the patients after LAMS placement.…”

“…In the second case, once biliary stricture develops, simple removal of the stent can resolve this AE completely. As nicely shown by Bang et al ,1 most of these AEs can be prevented by anticipating stent removal at 3 weeks, differently from what is usually done for PS.…”

“…We read with great interest the paper by Bang et al ,1 which reported the results of a randomised controlled trial comparing endoscopic ultrasound (EUS)-guided placement of lumen-apposing metal stents (LAMS) (Hot Axios) versus plastic stents (PS) for the treatment of patients with walled-off pancreatic necrosis (WON). During the first phase of the study, a very high number of adverse events (AEs) (32.2%) occurred in the LAMS arm, including two patients with a buried stent, three with bleeding pseudoaneurysms that required coil embolisation and other three with stent-induced biliary stricture.…”