Fully covered self-expandable metal stents in biliary strictures caused by chronic pancreatitis not responding to plastic stenting: a prospective study with 2 years of follow-up

Management of Benign Biliary Stricture in Chronic Pancreatitis

Endoscopic therapy is the first line of management for chronic pancreatitis (CP)-related benign biliary strictures. Multiple plastic stents (MPS) exchanged at regular intervals and temporary placement of fully covered self-expanding metal stents (FCSEMS) are preferred modalities of endotherapy. FCSEMS placement is non-inferior to MPS and requires fewer sessions of endoscopic retrograde cholangiopancreatography than MPS placement. The presence of head calcifications, severe CP, and length of stricture are predictors of failure or recurrence after endotherapy. Failure of endotherapy should be considered after 1 year when surgery should be considered.

Lerch M, Mayerle J. Clinical Practice Guideline—Acute and Chronic Pancreatitis

BACKGROUND

Acute pancreatitis (AP) is among the commonest non-malignant admission diagnoses in gastroenterology. Its incidence in Germany lies between 13 and 43 per 100 000 inhabitants and is increasing. In 2017, 24 per 100 000 inhabitants were hospitalized for chronic pancreatitis.

METHODS

From October 2018 to January 2019, we systematically searched the literature for original articles, meta-analyses, and evidence-based guidelines that were published in German or English between 1960 and 2018.

RESULTS

30-50% of cases of acute pancreatitis are caused by gallstone disease, and another 30-50% are due to alcohol abuse. The diagnosis is made when at least two of the following three criteria are met: typical abdominal pain, elevation of serum lipase, and characteristic imaging findings. If those criteria are ambiguous, transabdominal sonography is indicated. The early initiation of food intake lowers the rate of infected pancreatic necrosis, organ failure, or death (odds ratio 0.44; 95% confidence interval [0.2; 0.96]). In AP, Ringer's lactate solution should be preferred for fluid resuscitation, at 200-250 mL/hr for 24 hours. Severe pain should be treated with opiates.

CONCLUSION

The current German clinical practice guideline reflects the developments in the diagnosis and treatment of pancreatitis that have taken place over the past few years. The long-term care and monitoring of patients with complication-free pancreatitis is the responsibility of primary care physicians and gastroenterologists.

Fully covered metal biliary stents: A review of the literature

Fully covered self-expandable metal stents (FCSEMS) represent the latest advancement of metal biliary stents used to endoscopically treat a variety of obstructive biliary pathology. A large stent diameter and synthetic covering over the tubular mesh prolong stent patency and reduce risk for tissue hyperplasia and tumor ingrowth. Additionally, FCSEMS can be easily removed. All these features address issues faced by plastic and uncovered metal stents. The purpose of this paper is to comprehensively review the application of FCSEMS in benign and malignant biliary strictures, biliary leak, and post-sphincterotomy bleeding.

Current advances in the management of chronic pancreatitis

Chronic pancreatitis is characterized by irreversible destruction of pancreatic parenchyma and its ductal system resulting from longstanding inflammation, leading to fibrosis and scarring due to genetic, environmental, and other risk factors. The diagnosis of chronic pancreatitis is made based on a combination of clinical features and characteristic findings on computed tomography or magnetic resonance imaging. Abdominal pain is the most common symptom of chronic pancreatitis. The main aim of treatment is to relieve symptoms, prevent disease progression, and manage complications related to chronic pancreatitis. Patients who do not respond to medical treatment or not a candidate for surgical treatment are usually managed with endoscopic therapies. Endoscopic therapies help with symptoms such as abdominal pain and jaundice by decompression of pancreatic and biliary ducts. This review summarizes the risk factors, pathophysiology, diagnostic evaluation, endoscopic treatment of chronic pancreatitis, and complications. We have also reviewed recent advances in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-guided therapies for pancreatic duct obstruction due to stones, strictures, pancreatic divisum, and biliary strictures.

Incidence and Significance of Biliary Stricture in Chronic Pancreatitis Patients Undergoing Extracorporeal Shock Wave Lithotripsy for Obstructing Pancreatic Duct Stones

Background/Aims

This study assessed the significance of biliary stricture in symptomatic chronic pancreatitis patients requiring extracorporeal shock wave lithotripsy (ESWL) and endoscopic retrograde cholangiopancreatography (ERCP) to remove obstructing pancreatic calculi.

Methods

A total of 97 patients underwent ESWL followed by ERCP to remove pancreatic calculi between October 2014 and October 2017 at Virginia Mason Medical Center. Significant biliary stricture (SBS) was defined as a stricture with upstream dilation on computed tomography scan or magnetic resonance cholangiopancreatography scans accompanied by cholestasis and/or cholangitis. SBS was initially managed by either a plastic stent or fully covered self-expandable metallic stent (fcSEMS). If the stricture did not resolve, the stent was replaced with either multiple plastic stents or another fcSEMS. Data were collected by retrospectively reviewing the medical records.

Results

Biliary strictures were noted in approximately one-third of patients (34/97, 35%) undergoing ESWL for pancreatic calculi. Approximately one-third of the biliary strictures (11/34, 32%) were SBS. Pseudocysts were more frequently found in those with SBS (36% vs 8%, p=0.02), and all pseudocysts in the SBS group were located in the pancreatic head. The initial stricture resolution rates with fcSEMSs and plastic prostheses were 75% and 29%, respectively. The overall success rate for stricture resolution was 73% (8/11), and the recurrence rate after initial stricture resolution was 25% (2/8).

Conclusions

Although periductal fibrosis is the main mechanism underlying biliary stricture development in chronic pancreatitis, inflammation induced by obstructing pancreatic calculi, including pseudocysts, is an important contributing factor to SBS formation during the acute phase.

A Network Meta-analysis of Surgery for Chronic Pancreatitis: Impact on Pain and Quality of Life

BACKGROUND

The surgical operation associated with improved pain and quality of life (QoL) in patients with chronic pancreatitis (CP) is unknown.

METHOD

The Scopus, EMBASE, Medline and Cochrane databases were systematically searched until May 2019, and all randomised trials (RCTs) comparing surgical operations for CP pain were included in a network meta-analysis (NMA).

RESULTS

Four surgical operations for treating CP were directly compared in eight RCTs including 597 patients. Patients were mainly male (79%, 474/597) with alcoholic CP (85%, 382/452). Surgical operations included were pancreatoduodenectomy (224, 38%), Berne procedure (168, 28%), Beger procedure (133, 22%) and Frey procedure (72, 12%). The NMA revealed that the Beger procedure ranked best for pain relief, whilst the Frey procedure ranked best for postoperative QoL, postoperative pancreatic fistula rate and postoperative exocrine insufficiency rate during a median follow-up of 26 months (reported range 6-58 months). Overall the Frey procedure ranked best for the combination of primary outcome measures based on surface under cumulative ranking curve scores.

CONCLUSIONS

Overall the Frey procedure may perform the best for both pain relief and postoperative QoL in patients with CP. Further trials are warranted in defining the role of surgery in relation to endotherapy.

The use of a 532-nm laser fitted with a balloon and a cylindrical light diffuser to treat benign biliary stricture: a pilot study

Endoscopic management of benign biliary stricture (BBS) remains challenging. Stenting is currently used for BBS management, but refractory BBS remains problematic. The aim of this study was to assess the safety and feasibility of a dilation balloon-equipped cylindrical light diffuser for BBS in a large animal model. A total of seven mini-pigs were used in the current study. Laser settings were chosen based on the findings of a previous animal study. Five animals were used in a preliminary study to establish process conditions. BBSs were created in the common bile ducts of the other two animals by intraductal radiofrequency ablation (RFA) via endoscopic retrograde cholangiography (ERC). At 4 weeks post-RFA, laser ablation was performed using a customized balloon-equipped cylindrical diffuser at 10 W for 10 s while maintaining balloon inflation for 10 s at 5 atm. A follow-up ERC was performed at 4 weeks post-laser ablation and the animals were sacrificed for histologic evaluation. BBS was observed in all animals by ERC at 4 weeks post-RFA. The mean bile duct stricture diameter in the two animals as determined by ERC was 0.8 mm. Laser ablations were performed without technical difficulty and no adverse event was encountered. At 4 weeks post-laser ablation, mean biliary stricture diameter had dilated to 1.6 mm on cholangiographic finding. On histologic examination, inflammatory cell infiltration in lamina propria and dense collagen deposition were observed, but there was no evidence of bile duct perforation. The devised balloon-equipped cylindrical laser light diffuser appears to be safe and feasible for the treatment of BBS. However, further studies and modifications are required before it can be applied clinically as a monotherapy.

Risk Factors and Nomogram for Common Bile Duct Stricture in Chronic Pancreatitis: A Cohort of 2153 Patients

GOALS

To identify the risk factors and develop nomograms for common bile duct (CBD) stricture in chronic pancreatitis (CP) patients.

BACKGROUND

CBD stricture is a common complication in CP and has a variable clinical presentation ranging from asymptomatic to overt jaundice and cholangitis.

STUDY

Patients with CP admitted to Changhai Hospital (Shanghai, China) from January 2000 to December 2013 were enrolled. Cumulative rates of CBD stricture after onset and diagnosis of CP were calculated. Patients were randomly assigned, in a 2:1 ratio, to the training and validation cohort. On the basis of the training cohort, risk factors for CBD stricture and symptomatic CBD stricture were identified through Cox proportional hazards regression model, and nomograms was developed, respectively. Internal and external validations were performed based on the training and validation cohort, respectively.

RESULTS

With a total of 2153 patients, the median duration of follow-up was 7.0 years. CBD strictures were detected in 340 (15.8%) patients, whereas 159 of them were symptomatic. Male gender, age at onset of CP, smoking, body mass index, and morphology of main pancreatic duct were identified risk factors for CBD stricture development. Age at onset of CP, body mass index, and type of pain were identified risk factors for symptomatic CBD stricture development. Both nomograms achieved good concordance indexes with well-fitted calibration curves.

CONCLUSIONS

The nomogram achieved an individualized prediction of symptomatic CBD stricture development in CP patients. It may help the early diagnosis and intervention of symptomatic CBD stricture and reduce the rates of severe adverse events.

Benign biliary strictures: prevalence, impact, and management strategies

Benign biliary strictures (BBSs) may form from chronic inflammatory pancreaticobiliary pathologies, postoperative bile-duct injury, or at biliary anastomoses following liver transplantation. Treatment aims to relieve symptoms of biliary obstruction, maintain long-term drainage, and preserve liver function. Endoscopic therapy, including stricture dilatation and stenting, is effective in most cases and the first-line treatment of BBS. Radiological and surgical therapies are reserved for patients whose strictures are refractory to endoscopic interventions. Response to treatment is dependent upon the technique and accessories used, as well as stricture etiology. In this review, we discuss the various BBS etiologies and their management strategies.

[Endoscopic and surgical treatment of chronic pancreatitis]

With an increasing number of hospital admissions, an average of 16-to 20 days in hospital per year, 34% of patients constantly taking pain medication, 57% in need of enzyme supplementation, and 29% with diabetes mellitus, chronic pancreatitis is a debilitating disease of high socio-economic relevance. In total, 33% of all patients suffering from chronic pancreatitis can no longer practice their original profession. The number of unemployed chronic pancreatitis patients due to prolonged stays in hospital or continued alcohol abuse is known to be as high as 40%. Continued alcohol abuse with a hazard ratio (HR) of 1.6, smoking with a HR of 1.4, and the presence of liver cirrhosis with a HR of 2.5 negatively affects the prognosis of chronic pancreatitis. In a patient cohort burdened with high co-morbidity, endoscopic therapy can provide short-term relief of symptoms. Endotherapy is the first line of management in chronic pancreatitis with symptomatic pancreatobiliary ductal obstruction. Further studies are required in certain key areas such as the use of fully covered self-expanding metallic stents for pancreatic ductal and biliary strictures. Long-term success rates can mainly be achieved by surgical procedures, which can be performed with acceptable morbidity in pancreatic centers. The current review focuses on the advantages and disadvantages of endoscopic and surgical treatment of chronic pancreatitis.

Single brand, fully-covered, self-expandable metal stent for the treatment of benign biliary disease: when should stents be removed?

The two most relevant endoscopic treatable benign biliary diseases (BBD) are benign biliary strictures (BBSs) and biliary leaks (BLs), often associated with high morbidity. The most common endoscopic treatment for biliary strictures involves placement of multiple plastic stents (PSs), with or without balloon dilation, followed by planned exchange of the stents. Thus, there continues to be high interest in pursuing alternative endoscopic approaches that may achieve better results with fewer interventions. In this setting, the use of a fully-covered, self-expandable metal stent (FCSEMS) is an attractive alternative to single or multiple PSs for the treatment of BBDs. A single metal stent can remain in place for a longer period of time before removal; however, the maximum time the stent can be remain in place is still not well defined. The aim of this review is to determine the removal time of the TaeWoong® FCSEMS, placed for BBD. According to our data analysis, considering the absence of loss of the covering of the FCSEMS and of any adverse events during and after stent removal, leaving the TaeWoong medical FCSEMS in situ for an 8 months' period seems to be acceptable for benign biliary diseases. Further studies need to evaluate their removability at 1 year.

Evidence-Based Surgical Treatments for Chronic Pancreatitis

BACKGROUND

If conservative treatment of chronic pancreatitis is unsuccessful, surgery is an option. The choice of the most suitable surgical method can be difficult, as the indications, advantages, and disadvantages of the available methods have not yet been fully documented with scientific evidence.

METHODS

In April 2015, we carried out a temporally unlimited systematic search for publications on surgery for chronic pancreatitis. The target parameters were morbidity, mortality, pain, endocrine and exocrine insuffi - ciency, weight gain, quality of life, length of hospital stay, and duration of urgery. Differences between surgical methods were studied with network meta-analysis, and duodenum-preserving operations were compared with partial duodenopancreatectomy with standard meta-analysis.

RESULTS

Among the 326 articles initially identified, 8 randomized controlled trials on a total of 423 patients were included in the meta-analysis. The trials were markedly heterogeneous in some respects. There was no significant difference among surgical methods with respect to perioperative morbidity, pain, endocrine and exocrine insufficiency, or quality of life. Duodenumpreserving procedures, compared to duodenopancreatectomy, were associated with a long-term weight gain that was 3 kg higher (p <0.001; three trials), a mean length of hospital stay that was 3 days shorter (p = 0.009; six trials), and a duration of surgery that was 2 hours shorter (p <0.001; five trials).

CONCLUSION

Duodenum-preserving surgery for chronic pancreatitis is superior to partial duodenopancreatectomy in multiple respects. Only limited recommendations can be given, however, on the basis of present data. The question of the best surgical method for the individual patient, in view of the clinical manifestations, anatomy, and diagnostic criteria, remains open.

Clinical outcome of endoscopic covered metal stenting for resolution of benign biliary stricture: Systematic review and meta-analysis

BACKGROUND AND AIM

Management of benign biliary stricture is challenging. Endoscopic therapy has evolved as the first-line treatment for various benign biliary strictures. However, covered self-expandable metal stents (CSEMS) have not been approved by the United States Food and Drug Administration for the treatment of benign biliary stricture. With this goal, we conducted the present systemic review and meta-analysis to evaluate the efficacy and safety of endoscopic stenting with CSEMS in the treatment of benign biliary stricture.

METHODS

Systematic review and meta-analysis by searching PubMed, MEDLINE and Embase databases.

RESULTS

In total, 37 studies (1677 patients) fulfilled the inclusion criteria. Pooled stricture resolutions were achieved in 83% of cases. Median stent dwelling time was 4.4 months, with median endoscopic retrograde cholangiopancreatography sessions of 2.0. Stricture recurrence at 4-year follow up was 11% (95% CI, 8-14%). Pooled complication rate was 23% (95% CI, 20-26%).

CONCLUSIONS

Placement of CSEMS is effective in the treatment of benign biliary stricture with relatively short stenting duration and low long-term stricture recurrence rate. However, more prospectively randomized studies are required to confirm the results.

Effective treatment of benign biliary strictures with a removable, fully covered, self-expandable metal stent: A prospective, multicenter European study

BACKGROUND

Temporary placement of removable, fully covered, self-expandable metal stents (fcSEMS) for treatment of benign biliary strictures (BBS) has been reported to be effective. However, the optimal extraction time point remains unclear and stent migration has been a major concern.

OBJECTIVE

The objective of this study was to evaluate the efficacy and safety of this treatment modality using an fcSEMS with a special antimigration design and prolonged stent indwell time.

METHODS

We performed a prospective, single-arm study at six tertiary care centers in Europe. Patients with BBS underwent endoscopic or percutaneous implantation of an fcSEMS (GORE® VIABIL® Biliary Endoprosthesis, W.L. Gore & Associates, Flagstaff, AZ, USA). The devices were scheduled to be removed nine months later, and patients were to return for follow-up for an additional 15 months.

RESULTS

Forty-three patients were enrolled in the study. Stricture etiology was chronic pancreatitis in the majority of patients (57.5%). All fcSEMS were placed successfully, either endoscopically (76.7%) or percutaneously (23.3%). Stent migration was observed in two patients (5.2%). Primary patency of the SEMS prior to removal was 73.0%. All attempted stent removals were successful. At removal, stricture was resolved or significantly improved without need for further therapy in 78.9% of patients. Stricture recurrence during a follow-up of two years post-implant was observed in two patients.

CONCLUSIONS

Temporary placement of the fcSEMS is a feasible, safe and effective treatment for BBS. The design of the device used in this study accounts for very low migration rates and facilitates easy stent retrieval, even after it has been in place for up to 11 months.

Temporary placement of fully covered self-expandable metal stents for the treatment of benign biliary strictures

BACKGROUND

Endoscopic treatment of benign biliary strictures (BBS) can be challenging.

OBJECTIVE

To evaluate the efficacy of fully covered self-expandable metal stents (FCSEMS) in BBS.

METHODS

Ninety-two consecutive patients with BBS (chronic pancreatitis (n = 42), anastomotic after liver transplantation (n = 36), and post biliary surgical procedure (n = 14)) were included. FCSEMS were placed across strictures for 6 months before endoscopic extraction. Early success rate was defined as the absence of biliary stricture or as a minimal residual anomaly on post-stent removal endoscopic retrograde cholangiopancreatography (ERCP). Secondary outcomes were the final success and stricture recurrence rates as well as procedure-related morbidity.

RESULTS

Stenting was successful in all patients. Stenting associated complications were minor and occurred in 22 (23.9%) patients. Migration occurred in 23 (25%) patients. Stent extraction was successful in all but two patients with proximal stent migration. ERCP after the 6 months stenting showed an early success in 84.9% patients (chronic pancreatitis patients: 94.7%, liver transplant: 87.9%, post-surgical: 61.5%) (p = 0.01). Final success was observed in 57/73 (78.1%) patients with a median follow-up of 12 ± 3.56 months. Recurrence of biliary stricture occurred in 16/73 (21.9%) patients.

CONCLUSIONS

FCSEMS placement is efficient for patients with BBS, in particular for chronic pancreatitis patients. Stent extraction after 6 months indwelling, although generally feasible, may fail in a few cases.

Endoscopic management of benign biliary strictures

Endoscopic management of biliary obstruction has evolved tremendously since the introduction of flexible fiberoptic endoscopes over 50 years ago. For the last several decades, endoscopic retrograde cholangiopancreatography (ERCP) has become established as the mainstay for definitively diagnosing and relieving biliary obstruction. In addition, and more recently, endoscopic ultrasonography (EUS) has gained increasing favor as an auxiliary diagnostic and therapeutic modality in facilitating decompression of the biliary tree. Here, we provide a review of the current and continually evolving role of gastrointestinal endoscopy, including both ERCP and EUS, in the management of biliary obstruction with a focus on benign biliary strictures.

Outcome of stenting in biliary and pancreatic benign and malignant diseases: A comprehensive review

Endoscopic stenting has become a widely method for the management of various malignant and benign pancreatico-biliary disorders. Biliary and pancreatic stents are devices made of plastic or metal used primarily to establish patency of an obstructed bile or pancreatic duct and may also be used to treat biliary or pancreatic leaks, pancreatic fluid collections and to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis. In this review, relevant literature search and expert opinions have been used to evaluate the outcome of stenting in biliary and pancreatic benign and malignant diseases.

No Distal Migration in Unfixed Versus Fixed Cell Structure Covered Self-Expanding Metal Stents for Treatment of Benign Biliary Disease

BACKGROUND

Fully covered self-expandable metal stents (FCSEMS) are increasingly used for treatment of benign common bile duct (CBD) stricture or leakage, but dislodgement of FCSEMS is frequent.

AIMS

To compare dislocation rate and clinical outcome of a standard fixed cell structure FCSEMS (S-FCSEMS) to a novel FCSEMS with an unfixed cell structure (N-FCSEMS).

METHODS

We performed a retrospective analysis of all patients with FCSEMS insertion for benign biliary disease at our Hospital from 03/2008 to 03/2014. Both stent types N-FCSEMS and S-FCSEMS were applied as available unrelated to the indication.

RESULTS

Twenty-nine patients (S-FCSEMS: 18, N-FCSEMS: 11) were included. Stent placement was technically successful in 28/29 (96.6 %) patients; stent removal was successful in 26/27 (96.2 %). Two patients with N-FCSEMS were excluded due to unsuccessful placement and withdrawal of consent for stent removal, respectively. Stent migration into the duodenum (distal migration) was observed in 9/18 (50 %) in the S-FCSEMS group compared to 0/9 in the N-FCSEMS (p < 0.005). FCSEMS migration into the CBD (proximal migration) was found in 2/18 (11 %, S-FCSEMS) versus 2/9 (22 %, N-FCSEMS, p = 0.514). A foreshortening of the N-FCSEMS occurred in 3/9 patients (33 %) compared to 0/18 S-FCSEMS (p = 0.08). Clinical resolution of the treated CBD-disease was observed in 5/9 (56 %, N-FCSEMS) versus 12/18 (67 %, S-FCSEMS) at the time of stent removal (p = 0.604) and in 0/9 and 10/18 (56 %) cases during follow-up, respectively (p < 0.005).

CONCLUSION

An unfixed cell structure of FCSEMS seems to prevent distal migration, but proximal migration still occurs and foreshortening of the N-FCSEMS constrains clinical outcome.

Endoscopic management of benign biliary strictures

Benign biliary strictures are a common indication for endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic management has evolved over the last 2 decades as the current standard of care. The most common etiologies of strictures encountered are following surgery and those related to chronic pancreatitis. High-quality cross-sectional imaging provides a road map for endoscopic management. Currently, sequential placement of multiple plastic biliary stents represents the preferred approach. There is an increasing role for the treatment of these strictures using covered metal stents, but due to conflicting reports of efficacies as well as cost and complications, this approach should only be entertained following careful consideration. Optimal management of strictures is best achieved using a team approach with the surgeon and interventional radiologist playing an important role.

An Update to Hepatobiliary Stents

Endoscopic stent placement is a common primary management therapy for benign and malignant biliary strictures. However, continuous use of stents is limited by occlusion and migration. Stent technology has evolved significantly over the past two decades to reduce these problems. The purpose of this article is to review current guidelines in managing malignant and benign biliary obstructions, current endoscopic techniques for stent placement, and emerging stent technology. What began as a simple plastic stent technology has evolved significantly to include uncovered, partially covered, and fully covered self-expanding metal stents (SEMS) as well as magnetic, bioabsorbable, drug-eluting, and antireflux stents.(1).

Novel biliary self-expanding metal stents: indications and applications

Endoscopic insertion of a self-expanding metal stent (SEMS) through a malignant common bile duct stricture is the first line of palliation for malignant jaundice. Patency of these stents remains a major concern. SEMS dysfunction can result from tumor ingrowth, overgrowth and/or clogging. Initial SEMS modifications involved covering the central part of the stent in order to reduce ingrowth and ultimately increase patency. Fully covered stents became available shortly after reports of their use in human patients. The potential removability and radial strength of SEMS have led to evaluation of their use in new indications including benign biliary strictures, post sphincterotomy bleeding and perforation. Other aspects of development include the addition of features such as anti-reflux valves, drug elution and spontaneous biodegradability. These aspects and their clinical implications are reviewed and discussed.

Endoscopic therapy for chronic pancreatitis

PURPOSE OF REVIEW

To summarize recent data on techniques, efficacy and complications of endoscopic management of chronic pancreatitis.

RECENT FINDINGS

Extracorporeal shock wave lithotripsy with or without endoscopic retrograde cholangiopancreatography is the first-line treatment for large painful obstructive pancreatic duct calculi. Use of preextracorporeal shock wave lithotripsy secretin could result in better stone clearance. The first-line treatment for dominant pancreatic duct strictures is placement of a single 10-Fr polyethylene stent with planned exchanges every 3 months until 1 year. Other endoscopic approaches that have shown good efficacy include placement of simultaneous multiple plastic stents and fully covered self-expanding metallic stents. Endoscopic options to treat chronic pancreatitis-associated benign biliary strictures include single and simultaneous multiple plastic stenting and fully covered self-expanding metallic stents. The European Society of Gastrointestinal Endoscopy recommends multiple plastic stenting for such strictures, although fully covered self-expanding metallic stents should be currently used under research settings. Endoscopic ultrasonography-guided cholangiopancreatography and pancreatobiliary drainage is an evolving option for chronic pancreatitis-related ductal obstruction after failed endoscopic retrograde cholangiopancreatography. Recent data have supported the safety and efficacy of endotherapy for chronic pancreatitis in children.

SUMMARY

Endotherapy is the first line of management in chronic pancreatitis with symptomatic pancreatobiliary ductal obstruction. Further studies are required in certain key areas such as use of fully covered self-expanding metallic stents for pancreatic ductal and biliary strictures and endoscopic ultrasonography-guided pancreatobiliary drainage after failed endoscopic retrograde cholangiopancreatography.

Covered self-expanding metal stents may be preferable to plastic stents in the treatment of chronic pancreatitis-related biliary strictures: a systematic review comparing 2 methods of stent therapy in benign biliary strictures

BACKGROUND

Covered self-expanding metal stents (CSEMS) are being increasingly used in the endoscopic treatment of benign biliary strictures (BBS). There is no solid evidence yet to support their routine use.

GOALS

To evaluate feasibility, success rate, and complications of CSEMS compared with multiple plastic stents (PS) in BBS in a systematic review.

STUDY

A systematic search of electronic databases (Medline, Scopus, and Embase) for studies published from 2000 to 2012 combined to hand-search of reference lists resulted 4977 articles. Out of 99 potentially relevant studies selected for full-text review, 12 CSEMS (376 patients) and 13 PS studies (570 patients) met the final inclusion criteria. A systematic review comparing the 2 methods was made using proportion meta-analysis.

RESULTS

A tendency to successful use of CSEMS in strictures related to chronic pancreatitis (CP) was shown: clinical success of 77% and 33% [95% confidence interval (CI), 61%-94% vs. 4%-63%, P=0.06] was achieved with CSEMS and PS at 12 months follow-up, respectively. There were no differences in the success rates of other etiologies except CP or in the early complications. In CSEMS, incidence of late adverse events was lower in CP-related strictures (3% vs. 67%, 95% CI, 0%-13% vs. 17%-99%, P=0.02). The median number of endoscopic retrograde cholangiopancreatographies was lower with CSEMSs: 1.5 versus 3.9 (P=0.002).

CONCLUSIONS

Improved clinical success with fewer endoscopic sessions and corresponding complication rate may be achieved with CSEMS treatment compared with PS in BBS secondary to CP. In other BBS etiologies, this systematic review remains inconclusive.

Successful management of benign biliary strictures with fully covered self-expanding metal stents

BACKGROUND & AIMS

Fully covered self-expanding metal stents (FCSEMS) are gaining acceptance for the treatment of benign biliary strictures. We performed a large prospective multinational study to study the ability to remove these stents after extended indwell and the frequency and durability of stricture resolution.

METHODS

In a nonrandomized study at 13 centers in 11 countries, 187 patients with benign biliary strictures received FCSEMS. Removal was scheduled at 10-12 months for patients with chronic pancreatitis or cholecystectomy and at 4-6 months for patients who received liver transplants. The primary outcome measure was removal success, defined as either scheduled endoscopic removal of the stent with no removal-related serious adverse events or spontaneous stent passage without the need for immediate restenting.

RESULTS

Endoscopic removal of FCSEMS was not performed for 10 patients because of death (from unrelated causes), withdrawal of consent, or switch to palliative treatment. For the remaining 177 patients, removal success was accomplished in 74.6% (95% confidence interval [CI], 67.5%-80.8%). Removal success was more frequent in the chronic pancreatitis group (80.5%) than in the liver transplantation (63.4%) or cholecystectomy (61.1%) groups (P = .017). FCSEMS were removed by endoscopy from all patients in whom this procedure was attempted. Stricture resolution without restenting upon FCSEMS removal occurred in 76.3% of patients (95% CI, 69.3%-82.3%). The rate of resolution was lower in patients with FCSEMS migration (odds ratio, 0.22; 95% CI, 0.11-0.46). Over a median follow-up period of 20.3 months (interquartile range, 12.9-24.3 mo), the rate of stricture recurrence was 14.8% (95% CI, 8.2%-20.9%). Stent- or removal-related serious adverse events, most often cholangitis, occurred in 27.3% of patients. There was no stent- or removal-related mortality.

CONCLUSIONS

In a large prospective multinational study, removal success of FCSEMS after extended indwell and stricture resolution were achieved for approximately 75% of patients. ClincialTrials.gov number, NCT01014390.

Endoscopic management of benign biliary strictures

The majority of recent studies of benign biliary strictures (BBSs) have reported on treatment of stenotic injuries following cholecystectomy, orthotopic liver transplantation, living donor liver transplantation, chronic pancreatitis, and different inflammatory conditions such as common bile-duct-related strictures. Information about previous surgical procedures is very important for making a BBS diagnosis. Diagnostic tools for indeterminate strictures have increased to include (1) highly specialized cytological techniques such as fluorescence in situ hybridization, (2) cholangioscopy, and (3) endoscopic ultrasound with fine needle aspiration (FNA) and intraductal ultrasound. Magnetic resonance cholangiopancreatography before endoscopic retrograde cholangiopancreatography (ERCP) usually provides an adequate map to plan the endoscopic therapy. After traversing the stricture with a guidewire and, occasionally, performing balloon dilatation, plastic stents continue to be the basic endotherapy, trying to insert the maximum possible number, with an exchange every 3 months during a 12-month period. Progressive stenting requires a median number of five ERCPs; therefore, it is technically demanding and burdensome but has an average of 80% long-term durable stricture dilation. For not-hilar BBS, fully covered self-expanding metal stents (FCSEMSs) are emerging as a promising therapy needing fewer of the endoscopist's technical skills and reducing ERCP procedures and, probably, costs. To equal a 10-mm diameter provided by a single FCSEMS, about three plastic stents placed side-by-side are needed. Manufacturers are working to improve FCSEMS designs to reduce migration rate and to allow an easy extraction after several months in place. Many studies have tried to show reproducible protocols for the duration of FCSEMS therapy and the results in different types of BBSs.

Endoscopic management of complications of chronic pancreatitis

Pseudocysts and biliary obstructions will affect approximately one third of patients with chronic pancreatitis (CP). For CP-related, uncomplicated, pancreatic pseudocysts (PPC), endoscopy is the first-choice therapeutic option. Recent advances have focused on endosonography-guided PPC transmural drainage, which tends to replace the conventional, duodenoscope-based coma immediately approach. Ancillary material is being tested to facilitate the endosonography-guided procedure. In this review, the most adequate techniques depending on PPC characteristics are presented along with supporting evidence. For CP-related biliary obstructions, endoscopy and surgery are valid therapeutic options. Patient co-morbidities (e.g., portal cavernoma) and expected patient compliance to repeat endoscopic procedures are important factors when selecting the most adapted option. Malignancy should be reasonably ruled out before embarking on the endoscopic treatment of presumed CP-related biliary strictures. In endoscopy, the gold standard technique consists of placing simultaneous, multiple, side-by-side, plastic stents for a one-year period. Fully covered self-expandable metal stents are challenging this method and have provided 50% mid-term success.

ERCP for biliary strictures associated with chronic pancreatitis

Chronic pancreatitis (CP)-related common bile duct (CBD) strictures are more difficult to treat endoscopically compared with benign biliary strictures because of their nature, particularly in patients with calcific CP. Before any attempt at treatment, malignancy must be excluded. Single plastic stents can be used for immediate symptom relief and as "bridge to surgery and/or bridge to decision," but are not suitable for definitive treatment of CP-related CBD strictures because of long-term poor results. Temporary simultaneous placement of multiple plastic stents has a high technical success rate and provides good long-term results.

Future developments in biliary stenting

Biliary stenting has evolved dramatically over the past 30 years. Advancements in stent design have led to prolonged patency and improved efficacy. However, biliary stenting is still affected by occlusion, migration, anatomical difficulties, and the need for repeat procedures. Multiple novel plastic biliary stent designs have recently been introduced with the primary goals of reduced migration and improved ease of placement. Self-expandable bioabsorbable stents are currently being investigated in animal models. Although not US Food and Drug Administration approved for benign disease, fully covered self-expandable metal stents are increasingly being used in a variety of benign biliary conditions. In malignant disease, developments are being made to improve ease of placement and stent patency for both hilar and distal biliary strictures. The purpose of this review is to describe recent developments and future directions of biliary stenting.

Effectiveness and safety of endoscopic treatment of benign biliary strictures using a new fully covered self expandable metal stent

Background. In patients with benign biliary strictures, the use of fully covered self-expandable metal stents (SEMS) has been proposed as an alternative to plastic stenting, but high quality prospective data are sparse. This study was performed to evaluate the long-term effectiveness and safety of a new fully covered SEMS for benign biliary strictures. Methods. All consecutive patients with benign biliary strictures were treated with placement of a fully covered SEMS (WallFlex) for 6 months. Short- and long-term stricture resolution, adverse events, and ease of stent removal were recorded. Results. 23 patients were enrolled. Stricture etiology was chronic pancreatitis (14), postorthotopic liver transplant (4), idiopathic (4), and biliary stones (1). All ERCPs were technically successful. All stents were successfully removed. Short-term stricture resolution was seen in 22/23 (96%) patients. Long-term success was 15/18 (83.3%). All 3 failures were patients with biliary strictures in the setting of chronic calcific pancreatitis. Conclusions. The use of the new SEMS for the treatment of benign biliary strictures led to short-term stricture resolution in the vast majority of patients. Over a long-term followup the success rate appears favorable compared to historical results achieved with multiple plastic stenting, particularly in patients with chronic pancreatitis. The study was registered with ClinicalTrials.gov (NCT01238900).

Comment on ESGE clinical guideline for biliary stenting

The European Society of Gastrointestinal Endoscopy (ESGE) guidelines for biliary stenting published in 2012 are summarised and discussed.