Outcomes of colon self-expandable metal stents for malignant vs benign indications at a tertiary care center and review of literature

BACKGROUND Endoscopic placement of a self-expandable metal stent(SEMS)is a minimally invasive treatment for use in malignant and benign colonic obstruction.However,their widespread use is still limited with a nationwide analysis showing only 5.4%of patients with colon obstruction undergoing stent placement.This underutilization could be due to perceived increase risk of complications with stent placement.AIM To review long-and short-term clinical success of SEMS use for colonic obstruction at our center.METHODS We retrospectively reviewed all the patients who underwent colonic SEMS placement over aeighteen year period (August 2004 through August 2022) at our academic center. Demographicsincluding age, gender, indication (malignant and benign), technical success, clinical success,complications (perforation, stent migration), mortality, and outcomes were recorded.RESULTSSixty three patients underwent colon SEMS over an 18-year period. Fifty-five cases were formalignant indications, 8 were for benign conditions. The benign strictures included diverticulardisease stricturing (n = 4), fistula closure (n = 2), extrinsic fibroid compression (n = 1), and ischemicstricture (n = 1). Forty-three of the malignant cases were due to intrinsic obstruction from primaryor recurrent colon cancer;12 were from extrinsic compression. Fifty-four strictures occurred on theleft side, 3 occurred on the right and the rest in transverse colon. The total malignant case (n = 55)procedural success rate was 95% vs 100% for benign cases (P = 1.0, NS). Overall complication ratewas significantly higher for benign group: Four complications were observed in the malignantgroup (stent migration, restenosis) vs 2 of 8 (25%) for benign obstruction (1-perforation, 1-stentmigration) (P = 0.02). When stratifying complications of perforation and stent migration there wasno significant difference between the two groups (P = 0.14, NS).CONCLUSIONColon SEMS remains a worthwhile option for colonic obstruction related to malignancy and has ahigh procedural and clinical success rate. Benign indications for SEMS placement appear to havesimilar success to malignant. While there appears to be a higher overall complication rate inbenign cases, our study is limited by sample size. When evaluating for perforation alone theredoes not appear to be any significant difference between the two groups. SEMS placement may bea practical option for indications other that malignant obstruction. Interventional endoscopistsshould be aware and discuss the risk for complications in setting of benign conditions. Indicationsin these cases should be discussed in a multi-disciplinary fashion with colorectal surgery.

Treatment of malignant gastric outlet obstruction with endoscopically placed self-expandable metal stents

Malignant gastroduodenal obstruction can occur in up to 20%of patients with primary pancreatic,gastric or duodenal carcinomas.Presenting symptoms include nausea,vomiting,abdominal distention,pain and decreased oral intake which can lead to dehydration, malnutrition,and poor quality of life.Endoscopic stent placement has become the primary therapeutic modality because it is safe,minimally invasive,and a cost-effective option for palliation.Stents can be successfully deployed in the majority of patients. Stent placement appears to lead to a shorter time to symptomatic improvement,shorter time to resumption of an oral diet,and shorter hospital stays as compared with surgical options.Recurrence of the obstructive symptoms resulting from stent occlusion,due to tumor ingrowth or overgrowth,can be successfully treated with repeat endoscopic stent placement in the majority of the cases.Both endoscopic stenting and surgical bypass are considered palliative treatments and,to date,no improvement in survival with either modality has been demonstrated.A tailored therapeutic approach,taking into consideration patient preferences and involving a multidisciplinary team including the therapeutic endoscopist,surgeon,medical oncologist, radiation therapist,and interventional radiologist, should be considered in all cases.

Efficacy and safety of limited endoscopic sphincterotomy before self-expandable metal stent insertion for malignant biliary obstruction

To evaluate the safety and efficacy of limited endoscopic sphincterotomy (ES) before placement of self-expandable metal stent (SEMS).METHODSThis was a retrospective analysis of 244 consecutive patients with unresectable malignant biliary obstruction, who underwent placement of SEMSs following limited ES from December 2008 to February 2015. The diagnosis of malignant biliary obstruction and assessment of patient eligibility for the study was established by a combination of clinical findings, laboratory investigations, imaging and pathological results. All patients were monitored in the hospital for at least 24 h following endoscopic retrograde cholangio pancreatography (ERCP). The incidence of immediate or early post-ERCP complications such as post-ERCP pancreatitis (PEP) and bleeding related to limited ES were considered as primary outcomes. Also, characteristics and complications according to the cancer type were classified.RESULTSAmong the 244 patients included, the underlying diagnosis was cholangiocarcinoma in 118 patients, pancreatic cancer in 79, and non-pancreatic or non-biliary malignancies in the remaining 47 patients. Early post-ERCP complications occurred in 9 patients (3.7%), with PEP in 7 patients (2.9%; mild, 6; moderate, 1) and mild bleeding in 2 patients (0.8%). There was no significant association between the incidence of post-ERCP complications and the type of malignancy (cholangiocarcinoma vs pancreatic cancer vs others, P = 0.696) or the type of SEMS used (uncovered vs covered, P = 1.000). Patients who had more than one SEMS placed at the first instance were at a significantly higher risk of post-ERCP complications (one SEMS vs two SEMS, P = 0.031). No other factors were predictive of post-ERCP complications.CONCLUSIONLimited ES is feasible and safe, and effectively facilitates the placement of SEMS, without any significant risk of PEP or severe bleeding.

Feasibility and safety of self-expandable metal stent in nonmalignant disease of the lower gastrointestinal tract

In recent years,self-expandable metal stents(SEMSs)have been employed to treat benign gastrointestinal strictures secondary to several conditions:Acute diverticulitis,radiation colitis,inflammatory bowel disease(IBD),and postanastomotic leakages and stenosis.Other applications include endometriosis and fistulas of the lower gastrointestinal tract.Although it may be technically feasible to proceed to stenting in the aforementioned benign diseases of the lower gastrointestinal tract,the outcome has been reported to be poor.In fact,in some settings(such as complicated diverticulitis and postsurgical anastomotic strictures),stenting seems to have a limited evidence-based benefit as a bridge to surgery,while in other settings(such as endometriosis,IBD,radiation colitis,etc.),even society guidelines are not able to guide the endoscopist through decisional algorithms for SEMS placement.The aim of this narrative paper is to review the scientific evidence regarding the use of SEMSs in nonmalignant diseases of the lower gastrointestinal tract,both in adult and pediatric settings.

Evaluation of anti-migration properties of biliary covered self-expandable metal stents

AIM: To assess anti-migration potential of six biliary covered self-expandable metal stents(C-SEMSs) by using a newly designed phantom model. METHODS: In the phantom model, the stent was placed in differently sized holes in a silicone wall and retracted with a retraction robot. Resistance force to migration(RFM) was measured by a force gauge on the stent end. Radial force(RF) was measured with a RF measurement machine. Measured flare structure variables were the outer diameter, height, and taper angle of the flare(ODF, HF, and TAF, respectively). Correlations between RFM and RF or flare variables were analyzed using a linear correlated model.RESULTS: Out of the six stents, five stents were braided, the other was laser-cut. The RF and RFM of each stent were expressed as the average of five replicate measurements. For all six stents, RFM and RF decreased as the hole diameter increased. For all six stents, RFM and RF correlated strongly when the stent had not fully expanded. This correlation was not observed in the five braided stents excluding the laser cut stent. For all six stents, there was a strong correlation between RFM and TAF when the stent fully expanded. For the five braided stents, RFM after full stent expansion correlated strongly with all three stent flare structure variables(ODF, HF, and TAF). The laser-cut C-SEMS had higher RFMs than the braided C-SEMSs regardless of expansion state.CONCLUSION: RF was an important anti-migration property when the C-SEMS did not fully expand. Once fully expanded, stent flare structure variables plays an important role in anti-migration.

Fully covered self-expandable metal stents for treatment of malignant and benign biliary strictures

AIM:To present a series of covered self-expandable metal stents(CSEMS) placed for different indications and to evaluate the effectiveness,complications and extractability of these devices.METHODS:We therefore retrospectively reviewed the courses of patients who received CSEMS due to malignant as well as benign biliary strictures and postsphincterotomy bleeding in our endoscopic unit between January 2010 and October 2011.RESULTS:Twenty-six patients received 28 stents due to different indications(20 stents due to malignant biliary strictures,six stents due to benign biliary strictures and two stents due to post-sphincterotomy bleeding).Biliary obstruction was relieved in all cases,regardless of the underlying cause.Hemostasis could be achieved in the two patients who received the stents for this purpose.Complications occurred in five patients(18%).Two patients(7%) developed cholecystitis,stents dislocated/migrated in other two patients(7%),and in one patient(3.6%) stent occlusion was documented during the study period.Seven stents were extracted endoscopically.Removal of stents was easily possible in all cases in which it was desired using standard forceps.Twelve patients underwent surgery with pylorus preserving duodenopancreatectomy.In all patients stents could be removed during the operation without difficulties.CONCLUSION:Despite the higher costs of these devices,fully covered self-expanding metal stents may be suitable to relief biliary obstruction due to bile duct stenosis,regardless of the underlying cause.CSEMS may also represent an effective treatment strategy of severe post-sphincterotomy bleeding,not controlled by other measures.

Safety and efficacy of a partially covered self-expandable metal stent in benign pyloric obstruction

AIM:To evaluate the safety and efficacy of partially covered self-expandable metallic stents(SEMSs)in benign pyloric obstruction.METHODS:We retrospectively analyzed data from 10consecutive patients with peptic ulcer-related pyloric obstructive symptoms(gastric outlet obstruction scoring system(GOOSS)score of 1)between March 2012and September 2013.The patients were referred to and managed by partially covered SEMS insertion in our tertiary academic center.We assessed the technical success,symptom improvement,and adverse events after stenting.RESULTS:Early symptoms were improved just 3 d after SEMS placement in all 10 patients.The GOOSS score of all patients improved from 1 to 3.There were no serious immediate adverse events.The overall rate of being symptom free was 90%at a median of 11mo of follow-up(range:4-43 mo).Five patients were managed by a rescue SEMS because of failure of previous endoscopic balloon dilatation.Among them,four patients had sustained symptom improvement after the SEMS procedure.During the follow-up period,migration of the SEMS was observed in two patients(20.0%),both of whom had previous endoscopic balloon dilatation before SEMS insertion.CONCLUSION:Despite the small number in this study,partially covered SEMSs showed a favorable and safe outcome in the treatment of na?ve benign pyloric obstruction and in salvage treatment after balloon dilatation failure.

Self-expandable metal stents in patients with postoperative delayed gastric emptying after distal gastrectomy

AIM To investigate the efficacy and safety of endoscopic stent insertion in patients with delayed gastric emptying after gastrectomy.METHODS In this study, we prospectively collected data from patients who underwent stent placement for delayed gastric emptying(DGE) after distal gastrectomy between June 2010 and April 2017, at a tertiary referral academic center. Clinical improvement, complications, and consequences after stent insertion were analyzed.RESULTS Technical success was achieved in all patients(100%). Early symptom improvement was observed in 15 of 20 patients(75%) and clinical success was achieved in all patients. Mean follow-up period was 1178.3 ± 844.1 d and median stent maintenance period was 51 d(range 6-2114 d). During the follow-up period, inserted stents were passed spontaneously per rectum without any complications in 14 of 20 patients(70%). Symptom improvement was maintained after stent placement without the requirement of any additional intervention in 19 of 20 patients(95%).CONCLUSION Endoscopic stent placement provides prompt relief of obstructive symptoms. Thus, it can be considered an effective and safe salvage technique for post-operative DGE.

Use of a novel covered self-expandable metal stent with an anti-migration system for endoscopic ultrasound-guided drainage of a pseudocyst

The development of pseudocysts in patients with chronic pancreatitis has been reported in 23%-60% of cases and drainage is indicated when they become symptomatic. Endoscopic ultrasound-guided drainage with the placement of plastic or metallic stents to create a cystogastric anastomosis has been shown to be a reliable and efficacious maneuver. Metallic stent use appears to be a safe and effective alternative that shortens the length of time of the procedure and maintains a greater diameter in the cystogastric communication. However, important migration rates have been reported. The use of new metallic stents that are specially designed to prevent migration represents a promising development in the treatment of these group of patients that appears to be safe and effective for pseudocyst drainage and could importantly reduce migrationrates, while at the same time having the advantage of a single step procedure and a larger fistula diameter in the endoscopic cystogastric anastomosis.

Resolution of an esophageal leak and posterior gastric wall necrosis with esophageal self-expandable metal stents

The use of weight reduction surgeries has increased over the years with a higher proportion of these surgeries being sleeve gastrectomies,this has been associated with some complications including staple line leaks.We report a 32-year-old male who had undergone a laparoscopic gastric band surgery and subsequently a laparoscopic sleeve gastrectomy,this was complicated by both an staple line leak at the gastroesophageal junction as well as a large(> 4 cm) posterior gastric wall defect due to gastric wall necrosis. We used two co-axially inserted self-expandable stents(SEMS) in the management of this patient,5 stents were used over repeated endoscopy sessions and 20 wk. Both defects had resolved without the need for surgical intervention.This is the first reported case were SEMS are used for both a staple line leak as well as a gastric wall defect.We also review the literature on the use of SEMS in the management of leaks post weight reduction surgeries.

Placement of a fully covered self-expandable metal stent in a young patient with chronic pancreatitis

Plastic stent insertion is a treatment option for pancreatic duct stricture with chronic pancreatitis.However, recurrent stricture is a limitation after removing the plastic stent.Self-expandable metal stents have long diameters and patency.A metal stent has become an established management option for pancreatic duct stricture caused by malignancy but its use in benign stricture is still controversial.We introduce a young patient who had chronic pancreatitis and underwent several plastic stent insertions due to recurrent pancreatic duct stricture.His symptoms improved after using a fully covered self-expandable metal covered stent and there was no recurrence found at follow-up at the outpatient department.

Self-expandable metal stents for achalasia: Thinking out of the box!

Achalasia is a primary motor disorder of the esophagus diagnosed manometrically in the clinical setting of dysphagia to both solids and liquids. Currently established treatment options include pneumatic dilation, laparoscopic Heller myotomy, botulinum toxin injection performed endoscopically, oral agents that relax the lower esophageal sphincter and esophagectomy for refractory, end-stage disease. Despite their effectiveness, a significant proportion of patients eventually relapses and needs retreatment. In this setting, several new techniques are under investigation promising future enrichment of our therapeutic armamentarium for achalasic patients. Among them, peroral endoscopic myotomy and selfexpandable metal stents placed across the gastroesophageal junction represent the most encouraging modalities, as initial studies assessing their efficacy and safety indicate. This review highlights the role of selfexpandable metal stents in the management of patients with achalasia. Their possible position in the therapeutic algorithm of achalasia along with established and novel techniques is also assessed. Finally, the need for large prospective randomized trials is underlined in order to elucidate the numerous relevant issues.

Endoscopic transpapillary gallbladder drainage with replacement of a covered self-expandable metal stent

Endoscopic self-expandable metal stent (SEMS) placement has become a standard palliative therapy for pa- tients with malignant biliary obstruction. Acute cholecystitis after SEMS placement is a serious complication. We report a patient with an acute cholecystitis after covered SEMS placement, who was managed successfully with endoscopic transpapillary gallbladder drainage (ETGBD) and replacement of the covered SEMS. An 85-year-old man with pancreatic cancer suffered from acute cholecystitis after covered SEMS placement. It was impossible to perform percutaneous transhepatic gallbladder drainage. After removal of the covered SEMS with a snare, a 7Fr double pigtail stent was placed between the gallbladder and duodenum, subsequently followed by another covered SEMS insertion into the common bile duct beside the gallbladder stent. The cholecystitis improved immediately after ETGBD. ETGBD with replacement of the covered SEMS thus proved to be effective for treatment of patients with acute cholecystitis after covered SEMS placement.

Endoscopic Ultrasound-Guided Biliary Drainage with a Fully Covered Self-Expandable Metal Stent for Malignant Obstructive Jaundice

Objective: To study the therapeutic effect of Endoscopic ultrasound-guided biliary drainage (EUS-BD) with a nitinol fully covered self-expandable metal stent in patients with malignant obstructive jaundice when endoscopic retrograde cholangiopancreatography (ERCP) fails. Methods: From January 2016 January 2018, all patients with malignant obstructive jaundice during hospitalization underwent EUS-guided biliary drainage with a nitinol fully covered self-expandable metal stent, and the operation success rate, the clinical success rate, complications, length of hospital stay and survival time were observed. Results: Of 36 patients, 34 cases had successful operation;the operation success rate was 94.44% (34/36). The clinical success rate was 88.89% (32/36). Hemobilia occurred in 1, acute cholangitis in 1, and bile peritonitis in 1;improved after conservative treatment, the complication rate is 8.33% (3/36). Hospital stay and survival time was 21.54 ± 4.73 days and 220.54 ± 54.76 days, respectively. Conclusion: EUS-BD with a nitinol fully covered self-expandable metal stent may be a feasible and effective treatment option in patients with malignant biliary obstruction when ERCP fails.

Safety and efficacy of Kaffes intraductal self-expanding metal stents in the management of post-liver transplant anastomotic strictures

BACKGROUND Endoscopic management is the first-line therapy for post-liver-transplant anas-tomotic strictures.Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months,data on safety and duration for metal stents in this setting is scarce.Due to limited access to endoscopic retrograde cholan-giopancreatography(ERCP)during the coronavirus disease 2019 pandemic in our centre,there was a change in practice towards increased usage and length-of-stay of the Kaffes biliary intraductal self-expanding stent in patients with suitable anatomy.This was mainly due to the theoretical benefit of Kaffes stents allowing for longer indwelling periods compared to the traditional plastic stents.METHODS Adult liver transplant recipients aged 18 years and above who underwent ERCP were retrospectively identified during a 10-year period through a database query.Unplanned admissions post-Kaffes stent insertion were identified manually through electronic and scanned medical records.The main outcome was the incidence of complications when stents were left indwelling for 3 months vs 6 months.Stent efficacy was calculated via rates of stricture recurrence between patients that had stenting courses for≤120 d or>120 d.RESULTS During the study period,a total of 66 ERCPs with Kaffes insertion were performed in 54 patients throughout their stenting course.In 33 ERCPs,the stent was removed or exchanged on a 3-month interval.No pancreatitis,perfor-ations or deaths occurred.Minor post-ERCP complications were similar between the 3-month(abdominal pain and intraductal migration)and 6-month(abdominal pain,septic shower and embedded stent)groups-6.1%vs 9.1%respectively,P=0.40.All strictures resolved at the end of the stenting course,but the stenting course was variable from 3 to 22 months.The recurrence rate for stenting courses lasting for up to 120 d was 71.4%and 21.4%for stenting courses of 121 d or over(P=0.03).There were 28 patients that were treated with a single ERCP with Kaffes,21 with removal after 120 d and 7 within 120 d.There was a significant improvement in stricture recurrence when the Kaffes was removed after 120 d when a single ERCP was used for the entire stenting course(71.0%vs 10.0%,P=0.01).CONCLUSION Utilising a single Kaffes intraductal fully-covered metal stent for at least 4 months is safe and efficacious for the management of post-transplant anastomotic strictures.

Endoscopic-ultrasound-guided biliary drainage with placement of electrocautery-enhanced lumen-apposing metal stent for palliation of malignant biliary obstruction:Updated meta-analysis

BACKGROUND Endoscopic ultrasound-guided biliary drainage using electrocautery-enhanced(ECE)delivery of lumen-apposing metal stent(LAMS)is gradually being re-cognized as a viable palliative technique for malignant biliary obstruction after endoscopic retrograde cholangiopancreatography(ERCP)failure.However,most of the studies that have assessed its efficacy and safety were small and hetero-geneous.Prior meta-analyses of six or fewer studies that were published 2 years ago were therefore underpowered to yield convincing evidence.AIM To update the efficacy and safety of ECE-LAMS for treatment of biliary ob-struction after ERCP failure.METHODS We searched PubMed,EMBASE,and Scopus databases from the inception of the ECE technique to May 13,2022.Primary outcome measure was pooled technical success rate,and secondary outcomes were pooled rates of clinical success,re-intervention,and adverse events.Meta-analysis was performed using a random-effects model following Freeman-Tukey double-arcsine transformation in R soft-ware(version 4.1.3).RESULTS Fourteen eligible studies involving 620 participants were ultimately included.The pooled rate of technical success was 96.7%,and clinical success was 91.0%.Adverse events were reported in 17.5%of patients.Overall reinter-vention rate was 7.3%.Subgroup analyses showed results were generally consistent.CONCLUSION ECE-LAMS has favorable success with acceptable adverse events in relieving biliary obstruction when ERCP is impossible.The consistency of results across most subgroups suggested that this is a generalizable approach.

Defining failure of endoluminal biliary drainage in the era of endoscopic ultrasound and lumen apposing metal stents

The role of endoscopy in pathologies of the bile duct and gallbladder has seen notable advancements over the past two decades.With advancements in stent technology,such as the development of lumen-apposing metal stents,and adoption of endoscopic ultrasound and electrosurgical principles in therapeutic endoscopy,what was once considered endoscopic failure has transformed into failure of an approach that could be salvaged by a second-or third-line endoscopic strategy.Incorporation of these advancements in routine patient care will require formal training and multidisciplinary acceptance of established techniques and collaboration for advancement of experimental techniques to generate robust evidence that can be utilized to serve patients to the best of our ability.

Revolutionizing palliative care:Electrocautery-enhanced lumenapposing metal stents in endoscopic-ultrasound-guided biliary drainage for malignant obstructions

Patients with malignant biliary obstruction,following endoscopic retrograde cholangiopancreatography(ERCP)failure could be referred for endoscopicultrasound-guided biliary drainage through electrocautery-enhanced(ECE)lumen-apposing metal stent(LAMS)placement.However,the efficacy and safety of ECE-LAMS in this scenario have remained debatable due to minimal scientific evidence.The current confirmed 91.0%clinical success,96.7%technical success,7.3%reintervention rate,and 17.5%adverse events,following the treatment of malignant biliary obstruction with ECE-LAMS delivery.Finally,ECE-LAMS proved to be a generalizable strategy for managing biliary obstruction for patients who were excluded from ERCP.

Role of endoscopic-ultrasound-guided biliary drainage with electrocautery-enhanced lumen-apposing metal stent for palliation of malignant biliary obstruction

In this editorial,we discuss the article by Peng et al in the recent issue of the World Journal of Gastrointestinal Surgery,focusing on the evolving role of endoscopicultrasound-guided biliary drainage(EUS-BD)with electrocautery lumen apposing metal stent(LAMS)for distal malignant biliary obstruction.Therapeutic endoscopy has rapidly advanced in decompression techniques,with growing evidence of its safety and efficacy surpassing percutaneous and surgical approaches.While endoscopic retrograde cholangiopancreatography(ERCP)has been the gold standard for biliary decompression,its failure rate approaches 10.0%,prompting the exploration of alternatives like EUS-BD.This random-effects meta-analysis demonstrated high technical and clinical success of over 90.0% and an adverse event rate of 17.5%,mainly in the form of stent dysfunction.Outcomes based on stent size were not reported but the majority used 6 mm and 8 mm stents.As the body of literature continues to demonstrate the effectiveness of this technique,the challenges of stent dysfunction need to be addressed in future studies.One strategy that has shown promise is placement of double-pigtail stents,only 18% received the prophylactic intervention in this study.We expect this to improve with time as the technique continues to be refined and standardized.The results above establish EUS-BD with LAMS as a reliable alternative after failed ERCP and considering EUS to ERCP upfront in the same session is an effective strategy.Given the promising results,studies must explore the role of EUS-BD as first-line therapy for biliary decompression.

Unveiling the potential of electrocautery-enhanced lumen-apposing metal stents in endoscopic ultrasound-guided biliary drainage

This editorial delves into Peng et al's article,published in the World Journal of Gastrointestinal Surgery.Peng et al's meta-analysis investigates the effectiveness of electrocautery-enhanced lumen-apposing metal stents(ECE-LAMS)in ultrasound-guided biliary drainage for alleviating malignant biliary obstruction.Examining 14 studies encompassing 620 participants,the research underscores a robust technical success rate of 96.7%,highlighting the efficacy of ECE-LAMS,particularly in challenging cases which have failed endoscopic retrograde cholangio pancreatography.A clinical success rate of 91.0% underscores its impact on symptom alleviation,while a reasonably tolerable adverse event rate of 17.5% is observed.However,the 7.3% re-intervention rate stresses the need for post-procedural monitoring.Subgroup analyses validate consistent outcomes,bolstering the applicability of ECE-LAMS.These findings advocate for the adoption of ECELAMS as an appropriate approach for biliary palliation,urging further exploration in real-world clinical contexts.They offer valuable insights for optimizing interventions targeting malignant biliary obstruction management.