LAUSR

ceived for transgastric or transduodenal endoscopic drainage of symptomatic pancreatic pseudocysts and walled-off necrosis (WON). Their inner diameter is large enough to allow direct endoscopic necrosectomy, and their wide flanges on both ends provide an effective anchorage with lower rates of migration. “Hot LAMS” systems are enhanced with an electrocautery tip that allows fast and easy stent delivery, and limits the use of ancillary tools and fluoroscopy. Many off-label indications for LAMSs have emerged, notably for endoscopic ultrasound (EUS)-guided biliary drainage, when endoscopic retrograde cholangiopancreatography fails or is not feasible [1]. Although the US Food and Drug Administration has approved a 60-day maximum stent indwell time, longer and sometimes permanent stent placements are performed, especially in patients with malignant disease. Overall, the decision to retrieve a LAMS and the timing of this should be part of a global strategy. A first prospective cohort of LAMS procedures for pancreatic fluid collections (PFCs) reported easy, successful and uneventful stent removal after a median (range) indwell time of 32 (2– 178) days in all 47 patients for whom retrieval was indicated [2]. Concerns about the timing of LAMS retrieval were raised in 2017, when Bang et al. warned of an excessive rate of severe adverse events (SAEs) in the interim audit of a monocentric trial comparing LAMSs to plastic stents for WON drainage. Among 12 patients randomized to the LAMS group, three had presented with severe bleeding due to pseudoaneurysms (at weeks 3– 5 post-placement) and two were found to have buried stents at the endoscopy that was scheduled for their removal (at weeks 5 and 6) [3]. The authors hypothesized that LAMS immobility favors mucosal overgrowth and friction with surrounding neovessels, whereas, conversely, double-pigtail plastic stents are mobile and gravitate towards the digestive lumen as the PFC resolves. Consequently, the 2018 ESGE guidelines [4] strongly recommended – with low quality evidence – LAMS retrieval within 4 weeks post-PFC drainage. Of note, after the amendment of the randomized trial by Bang et al. where a CT scan was performed at 3 weeks to assess WON resolution before subsequent stent retrieval, AE rates were similar in the LAMS and plastic stent groups (6.5% vs. 6.9%) [5]. Since then, data regarding AEs related to LAMS removal following drainage for PFCs have accumulated [6], and two recent high quality studies have brought new insights on the matter. In 2022, an 18-center, 5-year retrospective study was conducted in the UK and Ireland, collecting data from 1018 patients with “hot LAMS” PFC drainage (539WONs, 479 pancreatic pseudocysts). LAMS removal was attempted after a median time of 7 weeks, and beyond week 4 in 687 patients (80.2%). How trivial is lumen-apposing metal stent retrieval?