Modified fully covered self-expandable metal stents with antimigration features for benign pancreatic-duct strictures in advanced chronic pancreatitis, with a focus on the safety profile and reducing migration

Endoscopic Retrograde Cholangiopancreatography: Pancreatic Endoscopy

The evolution of pancreatic endoscopic retrograde cholangiopancreatography (ERCP) has transformed from a diagnostic tool to now a primarily therapeutic modality. Mainly utilized within the spectrum of pancreatitis, pancreatic ERCP can help resolve pancreatic duct (PD) leaks, disruptions, and pancreatic fluid collections. In chronic pancreatitis, ERCP is effective for the treatment of PD strictures and stones with the improvement of pancreatoscopy greatly facilitating targeted therapy. Pancreatoscopy also allows for accurate mapping of main duct intraductal papillary mucinous neoplasms, which can help guide surgical resection.

Current status and future perspectives for endoscopic treatment of local complications in chronic pancreatitis

Chronic pancreatitis is a progressive disease characterized by irregular fibrosis, cellular infiltration, and parenchymal loss within the pancreas. Chronic pancreatitis treatment includes lifestyle modifications based on disease etiology, dietary adjustments appropriate for each stage and condition, drug therapy, endoscopic treatments, and surgical treatments. Although surgical treatments of symptomatic chronic pancreatitis provide good pain relief, endoscopic therapies are recommended as the first-line treatment because they are minimally invasive. In recent years, endoscopic therapy has emerged as an alternative treatment method to surgery for managing local complications in patients with chronic pancreatitis. For pancreatic stone removal, a combination of extracorporeal shock wave lithotripsy and endoscopic extraction is used. For refractory pancreatic duct stones, intracorporeal fragmentation techniques, such as pancreatoscopy-guided electrohydraulic lithotripsy and laser lithotripsy, offer additional options. Interventional endoscopic ultrasound has become the primary treatment modality for pancreatic pseudocysts, except in the absence of disconnected pancreatic duct syndrome. This review focuses on the current status of endoscopic therapies for common local complications of chronic pancreatitis, including updated information in the past few years.

Fully Covered Self-expandable Metallic Stents for Refractory Benign Pancreatic Duct Strictures: A Systematic Review and Meta-analysis

BACKGROUND

Endoscopic treatment of refractory pancreatic duct (PD) strictures includes the placement of multiple plastic stents. Recent studies have shown the benefit of fully covered self-expandable metal stents (FCSEMS). This systematic review analyzes the efficacy and safety of FCSEMS in PD strictures.

METHODS

A comprehensive search of all suitable studies was conducted using the databases of MEDLINE, EMBASE, and Scopus from inception to November 2022. The outcomes assessed were efficacy and safety of FCSEMS in PD strictures. Using a random-effects inverse-variance model, the pooled proportions were calculated.

RESULTS

A total of 22 studies with 439 patients were included in the analysis. The pooled stricture resolution rate was 91.6% (95% CI: 87.4-95.7), while the pooled pain resolution rate was 84.9% (95% CI: 77.7-92.1). The pooled incidences of stent-related adverse events, including acute pancreatitis, pain requiring stent removal, and de novo stricture, were 3.9% (95% CI: 1.2-6.7), 0.8% (95% CI: 0.0-2.1), and 3.3% (95% CI: 0.7-5.8). The pooled incidence of stent migration, stricture recurrence, and the need for restenting were 12.9% (95% CI: 6.7-19.1), 9.3% (95% CI: 4.7-13.8), and 12.3% (95% CI: 6.9-17.8), respectively.

CONCLUSIONS

FCSEMSs can be considered in carefully selected patients with benign PD strictures with high resolution rate and acceptable adverse event rate. De-novo structure formation appears to be a significant problem. Further studies may help to decide the role of FCSEMS in the algorithm.

Endoscopic Retrograde Cholangiopancreatography for Management of Chronic Pancreatitis

Management of symptomatic chronic pancreatitis (CP) has shifted its approach from surgical procedures to minimally invasive endoscopic procedures. Increased experience and advanced technology have led to the use of endoscopic retrograde cholangiopancreatography (ERCP) as a therapeutic tool to provide pain relief and treat CP complications including pancreatic stones, strictures, and distal biliary strictures, pseudocysts, and pancreatic duct fistulas. In this article the authors will discuss the use of ERCP for the management of CP, its complications, recent advancements, and techniques from the most up to date literature available.

Advances in the Management of Pain in Chronic Pancreatitis

PURPOSE OF REVIEW

The data on recent advances in managing chronic pancreatitis (CP) pain is limited. This review highlights the role of endotherapy and the advances in the overall management of pain in CP.

RECENT FINDINGS

Of late, pancreatic biodegradable stents have been used in endotherapy with appreciable success. These include slow, medium, and fast degrading stents, which optimize the overall management of CP and could prevent the need for multiple procedures. Endoscopic ultrasound-guided celiac plexus block is reserved in selected patients to treat debilitating pain. Total pancreatectomy with islet autotransplantation in small duct disease has shown promising results. The indications for treating pain in CP with endoscopy and surgery need to be better defined. The complexity of pain control due to the incomplete understanding of pathomorphology makes the management of CP challenging. The current treatment methods are still evolving. Therapy aims to reduce pain, optimize recovery, maintain quality of life, and meet postoperative needs. Initial management includes lifestyle modification, nutrition optimization, risk factor reduction with abstinence from alcohol, cessation of tobacco and smoking. Supportive medical management involves the judicial use of analgesics, neuromodulators, antioxidants, pancreatic enzyme replacement for insufficiency, and diabetes management. Patients with intractable pain are ideal for therapeutic intervention. Being less invasive with an acceptable complication rate makes endotherapy the preferred first-line treatment. If found to be cost-effective, biodegradable stents can reduce the overall cost. Unfortunately, if patients remain symptomatic, surgery is preferred in case of failure or recurrence. For optimal results, appropriate patient selection is vital to maximizing outcomes.

Self-expanding metallic stent for refractory pancreatic duct stricture in chronic pancreatitis: A prospective follow-up study

BACKGROUND AND AIMS

In chronic pancreatitis, fully covered self-expanding metal stents (FCSEMS) are used to treat refractory pancreatic duct strictures. However, the FCSEMS design, effectiveness, safety, optimal stent indwelling time and patient selection remain unclear. This study aimed at evaluating technical success, clinical success and adverse events with FCSEMS in patients with symptomatic pancreatic duct stricture.

METHODS

The prospective study was conducted between May 2017 and May 2021 at a tertiary care center for chronic pancreatitis with refractory pancreatic duct stricture using controlled radial expansion (CRE) endoscopic retrograde cholangiopancreatography (ERCP) with FCSEMS (Niti-S, Bumpy stent, Taewoong Medical, Gimpo-Si, South Korea).

RESULTS

During the study period, a total of 11 patients underwent ERCP with FCSEMS for refractory pancreatic duct stricture. The mean age (± standard deviation, [SD]) was 32.36 ± 10.98 years and nine patients (81%) were male. Technical and clinical success rates were 100% and 90.9%, respectively. All patients had a history of prior pancreatic endotherapy. The median (inter quartile range, [IQR]) stent indwell time was seven (6-10) months. The median visual analogue scale (VAS) pain score pre and post-FCSEMS was 8 (5-8) and 1 (0-2), respectively (p-value 0.003). Median (IQR) follow-up after stent removal was 48 (40-60) months. One patient (9%) developed de novo main pancreatic duct (MPD) stricture, which was asymptomatic. None of the patients had cholangitis, pancreatitis, perforation, proximal migration or stent fracture.

CONCLUSION

The FCSEMS treatment appears to be safe, feasible and possibly an effective option for patients who have not responded to endoscopic plastic stenting.

Best Practices in Pancreatico-biliary Stenting and EUS-guided Drainage

Indications for endoscopic placement of endoluminal and transluminal stents have greatly expanded over time. Endoscopic stent placement is now a well-established approach for the treatment of benign and malignant biliary and pancreatic diseases (ie, obstructive jaundice, intra-abdominal fluid collections, chronic pancreatitis etc.). Ongoing refinement of technical approaches and development of novel stents is increasing the applicability and success of pancreatico-biliary stenting. In this review, we discuss the important developments in the field of pancreatico-biliary stenting, with a specific focus on endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-associated developments.

Endoscopic luminal stenting: Current applications and future perspectives

Endoscopic luminal stenting (ELS) represents a minimally invasive option for the management of malignant obstruction along the gastrointestinal tract. Previous studies have shown that ELS can provide rapid relief of symptoms related to esophageal, gastric, small intestinal, colorectal, biliary, and pancreatic neoplastic strictures without compromising cancer patients’ overall safety. As a result, in both palliative and neoadjuvant settings, ELS has largely surpassed radiotherapy and surgery as a first-line treatment modality. Following the abovementioned success, the indications for ELS have gradually expanded. To date, ELS is widely used in clinical practice by well-trained endoscopists in managing a wide variety of diseases and complications, such as relieving non-neoplastic obstructions, sealing iatrogenic and non-iatrogenic perforations, closing fistulae and treating post-sphincterotomy bleeding. The abovementioned development would not have been achieved without corresponding advances and innovations in stent technology. However, the technological landscape changes rapidly, making clinicians’ adaptation to new technologies a real challenge. In our mini-review article, by systematically reviewing the relevant literature, we discuss current developments in ELS with regard to stent design, accessories, techniques, and applications, expanding the research basis that was set by previous studies and highlighting areas that need to be further investigated.

Changing trends in the minimally invasive surgery for chronic pancreatitis

Chronic pancreatitis is a debilitating pancreatic inflammatory disease characterized by intractable pain resulting in poor quality of life. Conventional management of pancreatic pain consists of a step-up approach with medications and lifestyle modifications followed by endoscopic intervention. Traditionally surgery is reserved for patients who do not improve with other interventions. However, recent studies suggest that early surgical intervention is more beneficial as it can mitigate the progression of the pathological process and prevent loss of pancreatic function. Despite the widespread adoption of minimally invasive approaches in various gastrointestinal surgical disorders, minimally invasive surgery for chronic pancreatitis is slow to evolve. Technical difficulty due to severe inflammatory changes has been the major impediment to the widespread usage of minimally invasive surgery in chronic pancreatitis. With this background, the present review aimed to critically analyze the available evidence on the minimally invasive treatment of chronic pancreatitis. A Pub Med search of all relevant articles was performed using the appropriate keywords, parentheses, and Boolean operators. Most initial laparoscopic series have reported the feasibility of lateral pancreaticojejunostomy, considered an adequate procedure only in a small proportion of patients. The pancreatic head is the pacemaker of pain, so adequate decompression is critical for long-term pain relief. Recent studies have documented the feasibility of minimally invasive duodenum-preserving pancreatic head resection. With improvements in laparoscopic instrumentation and technological advances, minimally invasive surgery for chronic pancreatitis is gaining momentum. However, more high-quality evidence is required to document the superiority of minimally invasive surgery for chronic pancreatitis.

Long-term clinical outcomes of a fully covered self-expandable metal stent for refractory pancreatic strictures in symptomatic chronic pancreatitis: An 11-year follow-up study

BACKGROUND AND AIMS

A fully covered self-expandable metal stent (FCSEMS) has recently been applied in the management of chronic pancreatitis patients with pancreatic strictures. However, related long-term effects remain unclear. This study aimed to evaluate the long-term outcomes of FCSEMS placement in chronic pancreatitis patients with refractory strictures.

METHOD

We retrospectively reviewed our database for patients undergoing FCSEMS placement for refractory pancreatic strictures between September 2008 and December 2010. The main outcomes were technical, radiological, and clinical success, as well as recurrence and adverse events.

RESULTS

A total of 35 patients were included. Technical success was achieved in all patients. The median FCSEMS indwelling time was 3.2 months (interquartile range [IQR], 3.0-4.9 months). Radiological success was achieved in all patients (complete, n = 2; partial, n = 33). Clinical success was achieved in 29 patients (82.9%; complete analgesic cessation, n = 19; analgesic reduction >50%, n = 11). During the median follow-up of 136 months, (IQR, 85.8-145.5 months), eight patients (22.9%) experienced recurrence. The median interval from stent removal to recurrence was 24.9 months (IQR, 11.3-30.3 months). Biliary obstruction, an early adverse event, occurred in two patients (5.7%); the late adverse event stent-induced de novo stricture was observed in 17 patients (48.6%).

CONCLUSIONS

Our findings suggest that an FCSEMS is effective for relieving refractory strictures in chronic pancreatitis. However, FCSEMSs were associated with stent-induced de novo strictures in nearly half of the patients. Prospective studies are required to further evaluate the long-term efficacy and safety of FCSEMSs in chronic pancreatitis.

Soft self-expandable metal stent to treat painful pancreatic duct strictures secondary to chronic pancreatitis: a prospective multicenter trial

BACKGROUND AND AIMS

Fully covered self-expandable metal stents (FCSEMSs) may offer a treatment option for pain associated with a dilated pancreatic duct (PD) in chronic pancreatitis (CP), but optimal patient selection and FCSEMS design, efficacy, and safety remain uncertain. We studied an investigational pancreatic FCSEMS for treatment of CP-associated pain.

METHODS

Patients with painful CP, a dominant distal PD stricture, and PD dilation upstream were enrolled in a prospective, multicenter, single-arm trial studying 6-month indwell of a 4- to 6-cm-long soft pancreatic FCSEMS. Primary efficacy and safety endpoints were pain reduction 6 months after FCSEMS indwell (performance goal ≥53%) and PD stenting-related serious adverse events (SAEs), respectively (performance goal <32%). The primary efficacy endpoint was assessed in patients with sufficiently severe and frequent pain at FCSEMS placement as a first stent or in exchange of a plastic stent.

RESULTS

Among 67 patients (mean age, 52.7 ± 12.5 years; mean time since CP diagnosis, 6.4 ± 6.4 years), 34 (50.7%) had plastic stent placement within 90 days of FCSEMS placement, and 46 patients were eligible for the primary efficacy endpoint analysis. Technical success was 97.0% (65/67). The observed primary efficacy (26.1%, 12/46) and safety endpoints (31.3%, 21/67) failed to meet the a priori study hypotheses. Study stent migration occurred in 47.7% of patients (31/65).

CONCLUSIONS

Six-month treatment with an FCSEMS did not lead to an expected degree of pain reduction, and migrations and SAEs were common. Further study is needed to clarify optimal decompressive strategy, FCSEMS design, and patient selection. (Clinical trial registration number: NCT02802020.).

Development of novel biliary metal stent with coil-spring structure and its application in vivo swine biliary stricture model

Background

As of date, endoscopic biliary stenting with plastic stent (PS) and self-expandable metal stent (SEMS) have been widely used for the palliation of biliary tract strictures. However, these two stents have several limitations regarding the management of biliary strictures caused by intrahepatic and hilar cholangiocarcinoma. PS has short patency and also risks bile duct injury and bowel perforation. SEMS is difficult to revise when occluded by tumor overgrowth. To compensate for such shortcomings, we developed a novel biliary metal stent with coil-spring structure. The aim of this study was to investigate the feasibility and efficacy of the novel stent in a swine model.

Methods

The biliary stricture model was prepared in six mini-pigs using endobiliary radiofrequency ablation. Conventional PS (n=2) and novel stents (n=4) were deployed endoscopically. Technical success was defined as successful stent placement and clinical success was defined as >50% reduction of serum bilirubin level. Adverse events, stent migration, and endoscopic removability for one month after stenting were also assessed.

Results

The biliary stricture was successfully created in all animals. The technical success rate was 100 %, and the clinical success rate was 50% in the PS group and 75% in the novel stent group. In the novel stent group, the median pre- and post-treatment serum bilirubin levels were 3.94 and 0.3 mg/dL. Stent migration occurred in two pigs and two stents were removed by endoscopy. There was no stent-related mortality.

Conclusions

The newly designed biliary metal stent was feasible and effective in a swine biliary stricture model. Further studies are needed to verify the usefulness of the novel stent in the management of biliary strictures.

Pancreatic duct stents

Pancreatic duct stenting using endoscopy or surgery is widely used for the management of benign and malignant pancreatic diseases. Endoscopic pancreatic stents are mainly used to relieve pain caused by chronic pancreatitis and pancreas divisum, and to treat pancreatic duct disruption and stenotic pancreaticointestinal anastomosis after surgery. They are also used to prevent postendoscopic retrograde cholangiopancreatography pancreatitis and postoperative pancreatic fistula, treat pancreatic cancer, and locate radiolucent stones. Recent advances in endoscopic techniques, such as endoscopic ultrasonography and balloon enteroscopy, and newly designed stents have broadened the indications for pancreatic duct stenting. In this review we outlined the types, insertion procedures, efficacy, and complications of endoscopic pancreatic duct stent placement, and summarized the applications of pancreatic duct stents in surgery.

A prospective study of fully covered self-expandable metal stents for refractory benign pancreatic duct strictures

BACKGROUND/AIMS

Fully covered self-expanding metal stents (FCSEMSs) are a relatively novel option for treating painful main pancreatic duct refractory strictures in patients with chronic pancreatitis. Herein, we aimed to assess the efficacy, feasibility, and safety of FCSEMSs in this patient group.

METHODS

This prospective single-center study included patients who underwent endoscopic retrograde pancreatography with FCSEMS placement. The primary endpoints were the technical and clinical success rates. A reduction in visual analog scale pain score of >50% compared with that before stent placement was defined as clinical success. Secondary endpoints were resolution of pancreatic strictures on fluoroscopy during endoscopic retrograde pancreatography and the development of stent-related adverse events.

RESULTS

Thirty-six patients were included in the analysis. The technical success rate was 100% (n=36) and the clinical success rate was 86.1% (n=31). There was a significant increase in stricture diameter from 1.7 mm to 3.5 mm (p<0.001) after stent removal. The mean visual analog scale pain score showed statistically significant improvement. At 19 months of follow-up, 55.6% of the patients were asymptomatic. Stent migration (16.7%), intolerable abdominal pain (8.3%), development of de novo strictures (8.3%), and mild pancreatitis (2.8%) were the most common adverse events.

CONCLUSION

FCSEMS placement showed good technical and clinical success rates for achieving pain relief in patients with refractory main pancreatic duct strictures.

Covered self-expandable metal stents for pancreatic duct stricture: a systematic review and meta-analysis

Background and study aims  Placement of a covered (C)-self-expandable metal stent (SEMS) has been recently investigated as an alternative endoscopic treatment for main pancreatic duct stricture (MPDS) in chronic pancreatitis. Our aim was to carry out a systematic review and meta-analysis of studies quantifying efficacy and safety of C-SEMSs in the management of MPDS. Methods  A multiple database search was performed, including MEDLINE, Embase and Cochrane Library, from January 2000 to September 2020, to identify studies reporting the efficacy and safety of C-SEMSs in patients with MPDS. Stricture and pain resolution were investigated. Other outcomes included technical success, stent migration, stricture recurrence and need for repeated stent placement. Pancreatitis, severe abdominal pain requiring stent removal and de-novo stricture were recorded as complications. Results  Nineteen studies were identified, which included a total of 300 patients. C-SEMSs showed a pooled stricture resolution rate of 91 % [95 % confidence interval (CI), 85 %-96 %] and a pooled pain resolution rate of 92 % (95 % CI, 85 %-98 %). The pooled proportion for stricture recurrence was equal to 6 % (95 % CI, 1 %-14 %), while stent migration occurred in 33 of 300 patients, the pooled proportion being 7 % (95 % CI 1 %-15 %). The pooled mean stent duration was 133 days (95 % CI, 100-166 days). The most common complication was pancreatitis (3 %, 95 % CI 0 %-8 %), while de-novo stricture pooled proportion was 2 % (95 % CI, 0 %-5 %). Conclusions  C-SEMSs are effective and safe in the treatment of MPDS. However, there is a significant need for further high-quality, well-designed studies to produce evidence-based data on short and long-term efficacy, safety, costs of C-SEMSs, and also optimal stent duration.

Modified non-flared fully covered self-expandable metal stent for preoperative biliary drainage in pancreatic cancer

BACKGROUND AND AIM

Durable biliary drainage is essential in patients with pancreatic cancer in the era of effective neoadjuvant chemotherapy (NACT). Plastic stent (PS) tends to occlude easily, and current metal stents are designed for nonresectable cancer. We evaluated the efficacy of a modified non-flared fully covered self-expandable metal stent (M-FCSEMS) during the perioperative period in patients with resectable or borderline resectable pancreatic cancer.

METHODS

Consecutive patients with resectable or borderline resectable pancreatic ductal adenocarcinoma had a 12-mm M-FCSEMS (M-FCSEMS group) or 7-Fr PS (PS group) placed for biliary decompression before NACT or curative-intent surgery. The primary outcome was the re-intervention rate, and secondary outcomes were technical success, stent patency, and adverse events (AEs).

RESULTS

Endoscopic stent placement was technically successful in all 60 patients. Twenty-three patients underwent surgery and 37 NACT before surgery. Re-intervention was performed in 10.0% (3/30) of patients in the M-FCSEMS group and 36.7% (11/30) of patients in the PS group (P = 0.030). The stent patency at 180 days was 89.8% (95% confidence interval, 77.3-100.0%) in the M-FCSEMS group and 30.2% (95% confidence interval, 11.4-80.0%) in the PS group (P < 0.0001). Stent-related AEs occurred in 10.0% (3/30) in the M-FCSEMS group and 40.0% (12/30) in the PS group (P = 0.015). Surgery-related AEs occurred in 10.5% (2/19) and 14.3% (3/21) in the M-FCSEMS and PS groups (P = 0.549).

CONCLUSIONS

Modified non-flared fully covered self-expandable metal stents are effective and safe for durable biliary drainage in patients with resectable or borderline resectable pancreatic cancer during the perioperative period.

Endoscopic management of chronic pancreatitis

Chronic pancreatitis (CP) is an inflammatory process characterized by irreversible morphological changes in the pancreas. Pain is the predominant symptom observed during the course of CP. The etiopathogenesis of pain in CP is multifactorial and includes ductal hypertension due to obstruction of the pancreatic duct (PD), neuropathic causes, and extrapancreatic complications of CP like pseudocyst and distal biliary obstruction. A sizeable proportion of patients with CP are amenable to endoscopic treatment. The mainstay of endotherapy includes decompression of PD with one or more plastic stents in those with stricture, and fragmentation of PD calculi using extracorporeal shock wave lithotripsy. Nearly two-thirds of the patients achieve pain relief in the long term with endotherapy. Upfront assessment for the suitability of endotherapy is paramount to achieve the best outcomes. The predictors of poor response to endotherapy include multifocal disease, like those with multifocal strictures or multiple calculi throughout the pancreas, or a combination of both PD strictures and stones. With the emerging use of covered metal stents, the outcomes are likely to improve in cases with refractory PD strictures as well as CP-related distal biliary obstruction. The optimum stent design and indwell time of metal stents in cases with refractory PD strictures need further evaluation. Endoscopic ultrasonography has emerged as a complementary endoscopic modality in the management of CP as well as associated complications like pseudocysts, refractory pain, and vascular complications.

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.

Long-term outcomes of fully covered self-expandable metal stents versus plastic stents in chronic pancreatitis

Chronic pancreatitis (CP) related main pancreatic duct (MPD) stricture has been a challenge for endoscopists. Fully covered self-expandable metal stents (FC-SEMS) has been tried in CP patients, but the efficacy and safety are still controversial. Thus, we aim to compare the long-term clinical efficacy of FC-SEMS vs. plastic stent placement in persistent MPD strictures secondary to CP. Between 2007 and 2018, 80 chronic pancreatitis patients (58 males, median age 49 years), who underwent endoscopic placement of FC-SEMS (n = 26) and plastic stent (n = 54) for persistent MPD strictures after at least 3 months of initial single plastic stenting, were retrospectively analyzed during a median follow-up duration of 33.7 months. As a result, MPD stricture resolution rate was statistically higher in FC-SEMS group (87.0% vs. 42.0%, p < 0.001). Although immediate complications occurred similarly (38.5% vs. 37.0%, p = 0.902), spontaneous migration (26.9%) and de novo strictures (23.1%) were pronounced delayed complications in FC-SEMS group. Pain relief during follow-up was significantly higher in FC-SEMS group (76.9% vs. 53.7%, p = 0.046). The total procedure cost was similar in both groups ($1,455.6 vs. $1,596.9, p = 0.486). In comparison with plastic stent, FC-SEMS placement for persistent MPD strictures had favorable long-term clinical efficacy, with its typical complications like spontaneous migration and de novo strictures.

Comparison of clinical outcomes of multiple plastic stents and covered metal stent in refractory pancreatic ductal strictures in chronic pancreatitis- a systematic review and meta-analysis

BACKGROUND

Symptomatic pancreatic duct (PD) strictures in chronic pancreatitis refractory to single plastic stenting are usually managed by placement of multiple plastic stents (MPS). Fully covered self-expanding metallic stents (FCSEMS) have also been used in the management of these patients. However, the overall efficacy and safety of different types of stents is unclear from the currently available studies. We performed this meta-analysis to assess the efficacy and complications from MPS and FCSEMS in patients with PD strictures refractory to treatment with single plastic stents.

METHODS

Several electronic databases were searched for all the studies evaluating the outcome of placement of multiple plastic stents and fully covered metal stents in patients with PD strictures refractory to single plastic stenting. We calculated the Weighted Pooled Ratio (WPR) with Confidence Interval (CI) between the MPS and FCSEMS.

RESULTS

A total of 13 studies (including 2 abstracts) were included in the analysis. MPS were placed in 106 patients and FCSEMS in 192 patients. Improvement in pain after stenting (P = 0.794), risk of recurrence of pain after removal of stent (P = 0.48) and stricture recurrence after stent removal (P = 0.52) were comparable between MPS and FCSEMS. Risk of endoscopic re-intervention was also comparable between metal stents and MPS. However, FCSEMS was associated with overall higher risk of adverse events (P < 0.0001).

CONCLUSION

FCSEMS are comparable to multiple plastic stents in the treatment of symptomatic refractory PD strictures. However, use of FCSEMS is associated with increased risk of adverse events.

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.

Advances in stent therapy for malignant biliary obstruction

Malignant biliary obstruction (MBO), result of pancreatobiliary diseases is a challenging condition. Most patients with MBO are inoperable at the time of diagnosis, and the disease is poorly controlled using external-beam radiotherapy and chemotherapy. Biliary stent therapy emerged as a promising strategy for alleviating MBO and prolonging life. However, physicians find it difficult to determine the optimal type of biliary stent for the palliation of MBO. Here, we review the safety and efficacy of available biliary stents, used alone or in combination with brachytherapy, photodynamic therapy and advanced chemotherapeutics, in patients with pancreatobiliary malignancies and put forward countermeasures involving stent obstruction. Furthermore, 3D-printing stents and nanoparticle-loaded stents have broad application prospects for fabricating tailor-made biliary stents.

Endoscopic management of local complications of chronic pancreatitis

Endoscopic treatment of local complications in patients with chronic pancreatitis has gained ground over the surgical alternative in the last few years. The lower aggressiveness of endoscopic treatment, as well as the possibility to use it repeatedly in high-risk patients, has favored this development. In addition, the incorporation of new, highly accurate endoscopic therapeutic options such as pancreatoscopy-guided lithotripsy and endoscopic ultrasound-guided treatments make endoscopic treatment the first choice in many cases, despite discordant data in the literature. This article reviews the endoscopic treatment of the most common local complications of chronic pancreatitis, such as pancreatolithiasis, pseudocysts, and pancreatic, biliary, and duodenal ductal stenosis.

Which Are the Most Suitable Stents for Interventional Endoscopic Ultrasound?

Endoscopic ultrasound (EUS)-guided interventions provide easy access to structures adjacent to the gastrointestinal tract, effectively targeting them for therapeutic purposes. They play an important role in the management of pancreatic fluid collections (PFC) and bile duct (BD) and pancreatic duct (PD) drainage in cases of failed endoscopic retrograde cholangiopancreatography (ERCP) or gallbladder (GB) drainage. Specially designed stents and delivery systems for EUS-guided transluminal interventions allow various new applications and improve the efficacy and safety of these procedures. In fact, EUS-guided drainage has emerged as the treatment of choice for the management of PFC, and recent innovations such as fully covered metal stents (including lumen-apposing metal stents) have improved outcomes in patients with walled-off necrosis. Similarly, EUS-guided BD and PD drainage with specially designed stents can be beneficial for patients with failed ERCP due to an inaccessible papilla, gastric outlet obstruction, or surgically altered anatomy. EUS-guided GB drainage is also performed using dedicated stents in patients with acute cholecystitis who are not fit for surgery. Although the field of dedicated stents for interventional EUS is rapidly advancing with increasing innovations, the debate on the most appropriate stent for EUS-guided drainage has resurfaced. Furthermore, some important questions remain unaddressed, such as which stent improves clinical outcomes and safety in EUS-guided drainage. Herein, the current status and problems of the available stents are reviewed, including the applicable indications, long-term clinical outcomes, comparison between each stent, and their future prospects.

International consensus guidelines on interventional endoscopy in chronic pancreatitis. Recommendations from the working group for the international consensus guidelines for chronic pancreatitis in collaboration with the International Association of Pancreatology, the American Pancreatic Association, the Japan Pancreas Society, and European Pancreatic Club

BACKGROUND/OBJECTIVES

This paper is part of the international consensus guidelines on chronic pancreatitis, presenting for interventional endoscopy.

METHODS

An international working group with experts on interventional endoscopy evaluated 26 statements generated from evidence on 9 clinically relevant questions. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to evaluate the level of evidence. To determine the level of agreement, a nine-point Likert scale was used for voting on the statements.

RESULTS

Strong consensus was obtained for 15 statements relating to nine questions including the recommendation that endoscopic intervention should be offered to patients with persistent severe pain but not to those without pain. Endoscopic decompression of the pancreatic duct could be used for immediate pain relief, and then offered surgery if this fails or needs repeated endoscopy. Endoscopic drainage is preferred for portal-splenic vein thrombosis and pancreatic fistula. A plastic stent should be placed and replaced 2-3 months later after insertion. Endoscopic extraction is indicated for stone fragments remaining after ESWL. Interventional treatment should be performed for symptomatic/complicated pancreatic pseudocysts. Endoscopic treatment is recommended for bile duct obstruction and afterwards surgery if this fails or needs repeated endoscopy. Surgery may be offered if there is significant calcification and/or mass of the pancreatic head. Percutaneous endovascular treatment is preferred for hemosuccus pancreaticus. Surgical treatment is recommended for duodenal stenosis due to chronic pancreatitis.

CONCLUSIONS

This international expert consensus guideline provides evidenced-based statements concerning indications and key aspects for interventional endoscopy in the management of patients with chronic pancreatitis.

Efficacy of fully covered self-expandable metal stents for the management of pancreatic duct strictures in chronic pancreatitis: A systematic review and meta-analysis

BACKGROUND AND AIM

Recently, there has been burgeoning interest in the utilization of fully covered self-expandable metal stents (FCSEMSs) for managing main pancreatic duct strictures (MPDS) in chronic pancreatitis (CP). The primary aim was to investigate stricture resolution and recurrence rates of FCSEMS placement in patients with symptomatic CP complicated with MPDS.

METHODS

MEDLINE, EMBASE, and ISI Web of Science and Cochrane Library (up to December 2019) were searched to identify eligible studies. A meta-analysis of stricture resolution and recurrence rates was carried out using R. The crude rate of adverse events related to stent therapy was also calculated.

RESULTS

Ten studies involving 163 patients were included. The weighted pooled rate of MPDS resolution was 93% (95% confidence interval [95%CI] 84-99%) with substantial heterogeneity (I²  = 63%). Duration of stent placement more than 3 months did not result in a significantly higher resolution rate than that of 3 months or less (93% vs 93%, P = 0.91). The weighted pooled rate of stricture recurrence was 5% (95%CI: 0-12%). The stricture recurrence rate for patients with duration of stent placement more than 3 months (3%; 95%CI: 0-10%) was lower than that in patients with 3 months or less of stent placement (7%; 95%CI: 0-23%), but not significantly (P = 0.45). The overall rate of adverse events related to stent therapy was 34.9%, and spontaneous stent migration occurred in 14.1% of patients.

CONCLUSIONS

The use of FCSEMSs appears to be effective and safe in the management of MPDS caused by symptomatic CP.

Preliminary study of a modified, nonflared, short, fully covered metal stent for refractory benign pancreatic duct strictures (with videos)

BACKGROUND AND AIMS

Fully covered self-expanding metal stents (FCSEMSs) are considered to be more effective than plastic stents for the treatment of main pancreatic duct (MPD) strictures associated with chronic pancreatitis (CP) because of their larger diameter and exertion of a radial expansion force. However, the current FCSEMSs have several limitations. To overcome these, a novel modified nonflared FCSEMS was developed. In this study we conducted a prospective long-term follow-up evaluation of the efficacy of the novel FCSEMS for the treatment of refractory benign PD strictures in patients with CP.

METHODS

Consecutive patients with symptomatic CP associated with refractory MPD strictures were enrolled prospectively in this single-arm study. The nonflared FCSEMS was placed intraductally or transpapillary according to the location and length of the stricture. Stent removal was performed at 3 months after placement. The primary outcome was the resolution of the pancreatic ductal stricture.

RESULTS

Endoscopic placement of modified nonflared FCSEMSs was technically successful in all 25 patients. Intraductal FCSEMS placement was performed in 14 patients (56.0%). Stents of diameter 8 mm were used in 17 patients (68.0%). Stents of lengths 3 and 5 cm were inserted in 22 (88.0%) and 3 (12.0%) patients, respectively. In 1 patient (4.0%), stent migration developed. All other stents were removed successfully. After stent removal, resolution of the MPD stricture was confirmed in all patients, and no FCSEMS-related de novo stricture was observed. During the follow-up period (median, 34 months; interquartile range, 25-56) after the stents had been removed from the 25 patients, reintervention for recurrence of MPD stricture with abdominal pain was performed in 2 patients (8.0%).

CONCLUSIONS

Endoscopic placement of a novel modified nonflared FCSEMS resulted in long-term stricture resolution with pain relief and reduced the rate of stent-related adverse events, particularly stent migration and stent-induced de novo MPD stricture. (Clinical trial registration number: UMIN000035681.).

The Role of Endoscopic and Surgical Treatment in Chronic Pancreatitis

Chronic pancreatitis is a long-term illness leading to hospital admissions and readmission. This disease is often caused by heavy alcohol consumption and smoking. Patients with chronic pancreatitis suffer from acute or chronic pain episodes, recurrent pancreatitis, and complications, such as pseudocysts, biliary duct strictures, and pancreatic duct fistulas. Pancreatic duct strictures and stones may increase intraductal pressure and cause pain. Endoscopic therapy is aiming at decompressing the pressure and relieving the pain, most commonly with pancreatic duct stents and pancreatic duct stone retrieval. Early surgery is another option to treat the pain. In addition, endotherapy has been successful in treating complications related to chronic pancreatitis. The therapy should be individually chosen in a multidisciplinary meeting. Endoscopic therapy and surgery as treatment options for chronic pancreatitis are discussed in this review.

Endoscopic Ultrasound-Guided Pancreatic Transmural Stenting and Transmural Intervention

Endoscopic ultrasound (EUS)-guided pancreatic access is an emergent method that can be divided into the two main techniques of EUS-guided rendezvous and pancreatic transmural stenting (PTS). While many reports have described EUS-guided procedures, the indications, technical tips, clinical effects, and safety of EUS-guided pancreatic duct drainage (EUS-PD) remain controversial. This review describes the current status of and problems associated with EUS-PD, particularly PTS. We reviewed clinical data derived from a total of 334 patients. Rates of technical and clinical success ranged from 63% to 100% and 76% to 100%, respectively. In contrast, the rate of procedure-related adverse events was high at 26.7% (89/334). The most frequent adverse events comprised abdominal pain (n=38), acute pancreatitis (n=15), bleeding (n=9), and issues associated with pancreatic juice leakage such as perigastric fluid, pancreatic fluid collection, or pancreatic juice leaks (n=8). In conclusion, indications for EUS-PTS are limited, as is the evidence of its viability, due to the scarcity of expert operators. Despite improvements made to various devices, EUS-PTS remains technically challenging. Therefore, a long-term, large-scale, multicenter study is required to establish this technique as a viable alternative drainage method.

Fully covered self-expanding metal stents for refractory pancreatic duct strictures in symptomatic chronic pancreatitis, US experience

Background and study aims  Fully covered self-expanding metal stents (FCSEMS) have been used to treat refractory pancreatic duct strictures. We aimed to evaluate the feasibility, safety, and efficacy of FCSEMS in chronic pancreatitis with refractory pancreatic duct strictures. Patients and methods  This was a retrospective multicenter cases series of patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) with FCSEMS placement in the main pancreatic duct (MPD) at five tertiary care centers between February 2010 and June 2016. Primary endpoints were technical success, clinical success, and procedure-related morbidity. Secondary endpoints were pain relief at the end of follow-up and resolution of the pancreatic stricture on ERCP. Results  Thirty-three patients with previously drained stents, 76 % of whom were male, underwent ERCP with FCSEMS placement. Mean duration of follow-up was 14 months. All of the patients had prior therapy. The technical success rate for FCSEMS placement was 100 % (n = 33) and the clinical success rate was 93 % (was n = 31). Stents were removed after a median duration of 14.4 weeks. After stent removal, the diameter of the narrowest MPD stricture had increased significantly from 1 mm to 4.5 mm ( P  < 0.001). There was a statistically significant improvement on the Visual Analogue Scale (VAS) from a median of 8.5 to 2.5. At the end of the study, (n = 27) 87.1 % of patients reported significant pain reduction with reduced narcotic use. Conclusion  FCSEMS appeared to be a feasible, safe, and potentially effective Intervention in patients who had not responded to endoscopic therapy with plastic stents.

Modified non-flared fully covered self-expandable metal stent versus plastic stent for preoperative biliary drainage in patients with resectable malignant biliary obstruction

BACKGROUND AND AIM

Fully covered self-expandable metal stents (FCSEMS) may be better than plastic stents (PS) for preoperative biliary drainage (PBD) to relieve cholangitis or jaundice for resectable malignant biliary obstruction (MBO). However, modification of current FCSEMS designed originally for nonresectable MBO is needed to be a proper stent for PBD. The aim of this study was to evaluate the possible superiority of non-flared modified FCSEMS (M-FCSEMS) with 12-mm diameter and waist of central portion over PS in patients with resectable MBO.

METHODS

Eighty-five consecutive patients underwent PBD followed by operation from August 2015 to December 2017. In each M-FCSEMS and PS group, 29 patients were matched for age, sex, body mass index, and preoperative albumin and bilirubin levels.

RESULTS

The overall technical success rates of PBD using M-FCSEMS and PS were 100%. The time to operation was similar between groups (18.6 ± 10.8 vs 19.3 ± 11.6 days, respectively; P = 0.843). The prevalence of PBD-related adverse events (AEs) was 6.9% (2/29) in the M-FCSEMS group versus 27.6% (8/29) in the PS group (P = 0.037). Re-intervention before operation was required in 20.7% (6/29) of patients in the PS group but no patients in the M-FCSEMS group (P = 0.023). No differences were found between perioperative AEs in the M-FCSEMS and PS groups (27.5% vs 31.0%, respectively; P = 0.773).

CONCLUSION

Modified FCSEMS led to lower PBD-related AEs, re-intervention rate, and comparable perioperative AEs compared with PS. M-FCSEMS may be a potential novel stent for PBD in patients with resectable MBO.

Usefulness of newly modified fully covered metallic stent of 12 mm in diameter and anti-migration feature for periampullary malignant biliary strictures: Comparison with conventional standard metal stent

BACKGROUNDS

Fully covered self-expandable metal stent (FCSEMS) are preferred for distal malignant biliary stricture (MBS). However, stent migration is a major adverse event of FCSEMS, especially for far distal MBS. We evaluated the usefulness of newly modified FCSEMS (M-FCSEMS) having 12 mm in diameter and anti-migration feature to minimize stent migration compared with the conventional FCSEMS (C-FCSEMS).

METHODS

Total 102 patients were enrolled between January 2015 and September 2017 in this prospective comparative study; 50 were allocated to the M-FCSEMS group and 52 to the C-FCSEMS group. The primary outcome was stent migration, and the secondary outcomes were other adverse events, stent occlusion rate, and stent patency during the follow-up period.

RESULTS

The baseline characteristics of the two groups did not significantly differ. Endoscopic stent placement was technically successful in all patients. Stent migration occurred in 8.0% (4/50) of the patients in the M-FCSEMS group and 23.1% (12/52) of those in the C-FCSEMS group (P = 0.036). The other adverse events, including stent-related pancreatitis and cholecystitis did not significantly differ between the two groups (P = 0.415). Stent occlusion occurred in 23.9% (11/46) of the patients in the M-FCSEMS group and 37.5% (15/40) in the C-FCSEMS group (P = 0.171). Stent patency was significantly longer in the M-FCSEMS group than in the C-FCSEMS group (228 vs 157 days, P = 0.048).

CONCLUSIONS

Modified FCSEMS with 12-mm diameter and anti-migration feature significantly decreased the risk of stent migration and had longer patency compared with C-FCSEMS in patients with periampullary MBS.

Should a fully covered self-expandable biliary metal stent be anchored with a double-pigtail plastic stent? A retrospective study

BACKGROUND

The migration rate of fully covered self-expandable metal stents (FCSEMSs) has been reported to be between 14% to 37%. Anchoring of FCSEMSs using a double-pigtail plastic stent (DPS) may decrease migration.

AIM

To compare stent migration rates between patients who received FCSEMS alone and those who received both an FCSEMS and anchoring DPS.

METHODS

We conducted a retrospective analysis of endoscopy reporting system and medical records of 1366 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) with FCSEMS placement at the University of Kentucky health care. Between July 2015 and April 2017, 203 patients with FCSEMS insertion for the treatment of malignant biliary stricture, benign biliary stricture, post-sphincterotomy bleeding, bile leak, and cholangitis drainage were identified. The review and analysis were conducted through our endoscopy reporting system (ProVation^® MD) and medical records. Categorical data were analyzed using Chi-Square and Fischer exact test and continuous data using non-parametric tests. A regression analysis was performed to identify factors independently associated with increased risk of stent migration. We determined an FCSEMS migration endoscopically if the stent was no longer visible in the major papilla.

RESULTS

1366 patients had undergone ERCP by three advanced endoscopists over 21-mo period; among these, 203 patients had FCSEMSs placed. 65 patients had FCSEMSs with DPS, and 138 had FCSEMSs alone. 65 patients had FCSEMSs with DPS, and 138 had FCSEMSs alone. 95 patients had a malignant stricture, 82 patients had a benign stricture, 12 patients had bile leak, 12 patients had cholangitis, and nine patients had post-sphincterotomy bleeding. The migration rate in patients with anchored FCSEMSs with DPS was 6%, and those without anchoring DPS was 10% (P = 0.35). Overall, migration was reported in 18 patients with FCSEMSs placement out of 203 patients with an overall migration rate of 9.7%. There was no significant association between anchoring the FCSEMSs with DPS and the risk of stent migration. Only patients with the previous sphincterotomy and begin biliary stricture were found to have a statistically significant difference in the migration rate between patients who had FCSEMS with DPS and FCSEMS alone (P = 0.01).

CONCLUSION

The risk of migration of biliary FCSEMS was 9.7 %. Anchoring an FCSEMS with DPS does not decrease the risk of stent migration.

Uncovered versus covered stent in management of large bowel obstruction due to colorectal malignancy: a systematic review and meta-analysis

PURPOSE

To compare outcomes of uncovered stent and covered stent in management of large bowel obstruction secondary to colorectal malignancy.

METHODS

We conducted a search of electronic databases identifying studies comparing outcomes of uncovered and covered stents in management of large bowel obstruction secondary to colorectal malignancy. The Cochrane risk-of-bias tool and the Newcastle-Ottawa scale were used to assess the included studies. Random or fixed effects modelling were applied as appropriate to calculate pooled outcome data.

RESULTS

One randomised controlled trial (RCT) and nine observational studies, enrolling 753 patients, were identified. Uncovered stent was associated with lower risks of complications (RR 0.57 95% CI 0.44-0.74, P < 0.0001), tumour overgrowth (RR 0.29 95% CI 0.09-0.93, P = 0.04), and stent migration (RR 0.29 95% CI 0.17-0.48, P < 0.00001); longer duration of patency (MD 18.47 95% CI 10.46-26.48, P < 0.00001); lower need for stent reinsertion (RR 0.38 95% CI 0.17-0.86, P = 0.02); and higher risk of tumour ingrowth (RR 4.53 95% CI 1.92-10.69, P = 0.0008). Rates of technical success (RR 1.02 95% CI 0.99-1.04, P = 0.21), clinical success (RR 1.03 95% CI 0.98-1.08, P = 0.32), perforation (RD 0.01 95% CI - 0.03-0.02, P = 0.65), bleeding (RD 0.00 95% CI - 0.03-0.03, P = 0.98), stool impaction (RR 0.56 95% CI 0.12-2.04, P = 0.38) and stent obstruction (RR 2.23 95% CI 0.94-5.34, P = 0.97) were similar.

CONCLUSIONS

Our results suggest that uncovered stents are superior as indicated by fewer complications, lower rates of stent migration, longer duration of patency and a reduced need for stent reinsertion. The best available evidence is mainly derived from non-randomised studies; there is a need for more RCTs.

Safety, efficacy, and removability of a fully covered multi-hole metal stent in a swine model of hilar biliary stricture: a feasibility study

Background and study aims  Use of fully covered self-expandable metal stents (FCSEMS) for biliary drainage of malignant hilar biliary strictures is limited because of risk of cholangitis due to side branch obstruction. The aim of this study was to evaluate the safety and efficacy of unilateral placement of a multi-hole FCSEMS (FCSEMS-MH), which had a 2.5-mm hole in the center of the membrane on each cavity, in a swine model of hilar biliary stricture. Materials and methods  Six female mini pigs were included in this prospective study. The hilar biliary stricture model was prepared using an endobiliary radiofrequency ablation. FCSEMS-MHs were endoscopically inserted into the peri-hilar bile duct of all the animals. Outcomes were assessed in terms of adverse events (AEs) including cholangitis, stent patency, stent migration, and endoscopic stent removability for 1 month after stenting. Results  In terms of hilar biliary stricture types, two animals were of Bismuth type I and four were of type II. Technical success rate for endoscopic metal stenting was 100 % (6/6), and the functional success rate, which was evaluated 7 days after stent insertion, was also 100 % (5/5). The immediate overall AE rate was 0 %. There was no procedure-related mortality and stent migration did not occur in any animal during the 4-week stent indwelling period. Stents were removed from all six animals at 4 weeks post-stenting. Conclusion  Unilateral placement of FCSEMS-MH might be safe and effect for swine hilar biliary stricture models. However, long-term follow-up and comparative studies are needed to verify the usefulness of this stent.

Fully covered self-expanding metal stents for benign refractory pancreatic duct strictures in chronic pancreatitis

Background: Pancreatic duct (PD) stricture is a common adverse event in chronic pancreatitis (CP). Primary treatment for refractory PD strictures is endotherapy (ET), including the insertion of multiple plastic stents. In addition, fully covered self-expandable metal stents (FC-SEMSs) have also been successfully used. More long-term studies are necessary to clarify the complication rate and efficiency, however. Methods: This retrospective study was comprised of 17 patients with symptomatic CP and refractory fibrotic main pancreatic duct (MPD) stricture treated with FC-SEMSs between 2010-2018 at the Helsinki University Hospital. Treated strictures were located in the pancreatic head. Technical success was defined as the accurate positioning of the stent and resolution of the MPD stricture. Clinical success was defined as pain relief at the end of the follow-up. Results: In 12 patients (71%), stricture resolution was accomplished. Clinical success was achieved in 12 patients (71%). The median duration of stenting was 169 days (range 15-804). Ten patients (58.8%) underwent a follow-up of two years or more. Early complications (≤7 days) occurred in two patients (12%): one pancreatitis and one cholestasis. Late complications (≥7 days) included severe abdominal pain (n = 2, 12%), pancreatitis (n = 3, 18%), cholestasis (n = 1, 6%) and stent migration (n = 7, 35%). Significant differences in stricture resolution and pain improvement were evident in patients with stent migration compared to patients without stent migration [1(14.3%) vs. 11(84.6%), p = .004 and 2(28.6%) vs. 11(84.6%), p = .022]. Conclusion: FC-SEMS placement is a safe and potentially effective treatment for this challenging group of patients. However, stent migration appears to affect the clinical and technical outcome.

Pilot Study of Dumbbell-Type Covered Self-Expandable Metal Stent Deployment for Benign Pancreatic Duct Stricture (with Videos)

BACKGROUND

Fully-covered, self-expandable metal stents (FCSEMS) have been deployed to treat symptomatic chronic pancreatitis (CP) complicated with main pancreatic duct (MPD) stricture. Although this strategy can be effective, it has the disadvantages of stent migration or stent-induced ductal change. Removal of an FCSEMS can also be challenging in the face of distal migration because of MPD stricture. Dumbbell-type FCSEMS have been developed to prevent stent-induced ductal changes and improve removability when treating benign biliary stricture. This stent might also confer clinical benefits upon patients with MPD stricture.

AIMS

The present pilot study aimed to determine the feasibility and safety of deploying dumbbell-type FCSEMS in patients with CP complicated by MPD stricture.

METHOD

Stents were deployed in 22 patients with MPD stricture caused by CP and complicated by abdominal pain.

RESULTS

Strictures were located at the head (n = 19), body (n = 2), and head and tail (n = 1) of the MPD. Stents were deployed above the papilla in three patients. All stents were deployed for a median duration of 142 (range, 49-190) days and removed. The resolution of MPD strictures was confirmed by pancreatography in 19 (86.3%) patients. Two metal stents that spontaneously tore during removal from two patients had otherwise functioned normally. Only three patients developed recurrent MPD stricture during a median follow-up of 419 (range, 261-484) days..

CONCLUSIONS

Deployment of a dumbbell-type FCSEMS seems feasible for MPD stricture, and the rate of adverse events is acceptable.

Fully covered self-expandable metal stents to dilate persistent pancreatic strictures in chronic pancreatitis: long-term follow-up from a prospective study

BACKGROUND AND AIMS

Symptomatic main pancreatic duct (MPD) strictures secondary to chronic pancreatitis (CP) may benefit from endoscopic insertion of single or multiple plastic stents. MPD stricture resolution after single plastic stent removal is uncommon. The use of removable fully covered, self-expandable metal stents (FC-SEMSs) to dilate MPD strictures secondary to CP was evaluated.

METHODS

Patients with CP and symptomatic MPD stricture located in the head of the pancreas persisting for 3 months or more after placement of a single plastic stent were enrolled in a prospective single-arm trial. A nitinol FC-SEMS was inserted and removed after 6 months. The FC-SEMS diameter and length were chosen according to the stricture anatomy and MPD diameter above the stricture. Our primary objective was FC-SEMS removability. Secondary outcomes were MPD stricture resolution rate and adverse events.

RESULTS

Between December 2012 and October 2014, 15 patients (10 male, mean age 60 years) were enrolled. Pancreatic calcifications were present in 6 (40%) patients. Four patients (27%) had a history of alcohol abuse. In 10 patients, the FC-SEMS was inserted through the major papilla, whereas 5 patients (3 pancreas divisum, 2 dominant dorsal duct) received the stent through the minor papilla. One patient developed cholangitis after 24 hours due to occlusion of the biliary sphincterotomy from the FC-SEMS; cholangitis resolved after insertion of a plastic biliary stent. Complete distal migration of the FC-SEMS was reported in 7 patients (47%) (5 asymptomatic, 2 symptomatic with recurrence of pancreatitis). All migrations occurred with the 3-cm-long FC-SEMS. Four patients (27%) developed de novo stricture induced by the FC-SEMS at the level of the flared end and were excluded from the follow-up; 1 patient with FC-SEMS migration had failed stricture resolution. One patient was lost to follow-up. Finally, 9 patients with MPD stricture resolution had a mean follow-up of 38.9 months (range, 5.3-55.3 months), and 89% were asymptomatic.

CONCLUSIONS

FC-SEMS removability from the MPD in CP was feasible in all cases, and 90% of the patients were asymptomatic after 3 years. Migration seems more frequent with the 3-cm-long FC-SEMS. Occurrence of FC-SEMS-induced pancreatic strictures is a major issue and deserves further assessment. According to our experience, pancreatic FC-SEMSs have promising results, but a careful evaluation in the setting of clinical trials is needed.

10 Fr S-Type Plastic Pancreatic Stents in Chronic Pancreatitis Are Effective for the Treatment of Pancreatic Duct Strictures and Pancreatic Stones

AIM

Endoscopic pancreatic stenting for refractory pancreatic duct strictures associated with impacted pancreatic stones in chronic pancreatitis cases has yielded conflicting results. We retrospectively evaluated the efficacy of endoscopic treatment in chronic pancreatitis patients with pancreatic duct strictures.

METHODS

Pancreatic sphincterotomy, dilatation procedures, pancreatic brush cytology, and pancreatic juice cytology were routinely performed, and malignant diseases were excluded. After gradual dilatation, a 10 Fr plastic pancreatic stent was inserted. The stents were replaced every 3 months and removed after the strictures were dilated. Statistical analyses were performed to determine the risk of main pancreatic duct restenosis.

RESULTS

Endoscopic pancreatic stents were successfully placed in 41 of a total of 59 patients (69.5%). The median duration of pancreatic stenting was 276 days. Pain relief was obtained in 37 of 41 patients (90.2%). Seventeen patients (41.5%) had recurrence of main pancreatic duct stricture, and restenting was performed in 16 patients (average placement period 260 days). During the follow-up period, pancreatic cancer developed in three patients (5.1%). Multivariate analysis revealed that the presence of remnant stones after stenting treatment was significantly associated with a higher rate of main pancreatic duct restenosis (p = 0.03).

CONCLUSION

The use of 10 Fr S-type plastic pancreatic stents with routine exchange was effective for both short-term and long-term outcomes in chronic pancreatitis patients with benign pancreatic duct strictures and impacted pancreatic stones.

Long-term outcomes of 6-mm diameter fully covered self-expandable metal stents in benign refractory pancreatic ductal stricture

BACKGROUND AND AIM

Fully covered self-expandable metal stent (FCSEMS) placement has been tried for pancreatic ductal strictures in chronic pancreatitis. However, the long-term outcome of this procedure remains unknown. The present study aimed to investigate the procedural and long-term outcomes of FCSEMS placement in patients with benign refractory pancreatic ductal strictures.

METHODS

Between August 2011 and September 2015, 18 patients underwent endoscopic treatment with FCSEMS for benign refractory pancreatic ductal stricture. Technical success, clinical success, radiological success, and adverse events were assessed.

RESULTS

Stent placement was successful in all patients (technical success rate, 100%). Reduction in pain score of >50% was achieved in 15 of the 18 patients (clinical success rate, 83.3%). In all patients, stents could easily be removed at a median of 7.5 months (interquartile range [IQR], 6-13.6) after their insertion. FCSEMS migration did not develop in any patient. Ductal stricture was improved in 15 patients (radiological success rate, 83.3%). After definite stent removal, 13 of the 15 (86.7%) patients who had responded to pancreatic stenting maintained the response during follow up (median of 47.3 months; IQR, 7.4-57.1).

CONCLUSIONS

FCSEMS placement appears to be safe and effective for the treatment of benign refractory pancreatic ductal strictures as it can provide persistent improvement in the stricture in long-term follow up.

Management of Benign and Malignant Pancreatic Duct Strictures

The diagnosis and management of pancreatic strictures, whether malignant or benign, remain challenging. The last 2 decades have seen dramatic progress in terms of both advanced imaging and endoscopic therapy. While plastic stents remain the cornerstone of the treatment of benign strictures, the advent of fully covered metal stents has initiated a new wave of interest in calibrating the pancreatic duct with fewer sessions. In malignant disease, palliation remains the priority and further data are necessary before offering systematic pancreatic stenting.

A biodegradable non-covered self-expandable stent to treat pancreatic duct strictures in chronic pancreatitis: a proof of principle

BACKGROUND AND AIMS

In chronic pancreatitis (CP), fibrotic pancreatic duct (PD) strictures pose a therapeutic challenge, because endoscopic dilatation requires multiple procedures with suboptimal results. Biodegradable self-expandable stents (BD-SESs) may serve as an alternative in this setting.

METHODS

Patients with CP were eligible for this proof-of-principle study if at least 6 months of endoscopic dilatation with plastic stents had failed to resolve their PD stricture. The non-covered BD-SESs were expected to degrade within 3 to 6 months. Patients were followed at 3-monthly intervals for 1 year. Placement success and safety were the primary outcome parameters. Stricture resolution was assessed by ERCP after 6 months.

RESULTS

BD-SESs were successfully placed in all 19 patients without adverse events. In 2 cases, stent occlusion with sludge and stones was treated by a balloon swipe. One stent disintegrated during this procedure, after which placement of the plastic stent was resumed. A hyperplastic response was observed in 2 patients but did not result in functional obstruction. Stricture resolution was accomplished in 11 patients (technical success rate 58%). Six patients required further treatment of their PD stricture, 4 endoscopically and 2 surgically. Three additional patients underwent surgery for other reasons: 2 Whipple procedures for CP-related adverse events and one tail resection for an intraductal papillary mucinous neoplasm. The remaining 10 patients did not require further PD drainage (clinical success rate 52%).

CONCLUSIONS

These preliminary results show that BD-SESs are safe to use and able to resolve fibrotic PD strictures in CP. These encouraging outcomes warrant further testing.

Prognostic factors of response to endoscopic treatment in painful chronic pancreatitis

AIM

To evaluate the endoscopic treatment efficacy and prognostic factors of long-term response to treatment for painful chronic pancreatitis.

METHODS

This retrospective analysis identified 168 patients with painful chronic pancreatitis hospitalized during January 2010-January 2015 in a Romanian tertiary referral center. Data on demographics, medical history, alcohol consumption, smoking habit, clinical parameters, type and number of endoscopic procedures and hospital admissions number were collected from the medical charts and analyzed. The absence or substantial reduction of pain (mild pain) at the end of the follow-up associated with the technical success of endotherapy was considered as clinical success.

RESULTS

Among the 168 patients with painful chronic pancreatitis admitted to our department during the study period, 39 (23.21%) had optimal response to the medical therapy. One hundred and twenty-nine patients required endoscopic treatment. The median follow-up period was 15 mo (range, 0-60 mo). Overall, technical success of endotherapy was achieved in 105 patients (81.39%). More than two-thirds of patients (82.78%) had substantial improvement of pain after the endoscopic treatment, including frequency and severity of the pain attacks. Patients younger than 40 years had significantly more successful endoscopic procedures (P = 0.041). Clinical success was higher in non-smoking patients (P = 0.003). The hospital admission rate was higher in patients with recognized alcohol consumption (P = 0.03) and in smokers (P = 0.027). The number and location of pancreatic stones and locations of strictures did not significantly influence the technical success (P > 0.05) or the clinical success (P > 0.05).

CONCLUSION

Younger age than 40 years can be considered an important factor positively influencing endoscopic treatment outcome in patients with painful chronic pancreatitis.

Antireflux Metal Stent as a First-Line Metal Stent for Distal Malignant Biliary Obstruction: A Pilot Study

Background/Aims

In distal malignant biliary obstruction, an antireflux metal stent (ARMS) with a funnel-shaped valve is effective as a reintervention for metal stent occlusion caused by reflux. This study sought to evaluate the feasibility of this ARMS as a first-line metal stent.

Methods

Patients with nonresectable distal malignant biliary obstruction were identified between April and December 2014 at three Japanese tertiary centers. We retrospectively evaluated recurrent biliary obstruction and adverse events after ARMS placement.

Results

In total, 20 consecutive patients were included. The most common cause of biliary obstruction was pancreatic cancer (75%). Overall, recurrent biliary obstruction was observed in seven patients (35%), with a median time to recurrent biliary obstruction of 246 days (range, 11 to 246 days). Stent occlusion occurred in five patients (25%), the causes of which were sludge and food impaction in three and two patients, respectively. Stent migration occurred in two patients (10%). The rate of adverse events associated with ARMS was 25%: pancreatitis occurred in three patients, cholecystitis in one and liver abscess in one. No patients experienced non-occlusion cholangitis.

Conclusions

The ARMS as a first-line biliary drainage procedure was feasible. Because the ARMS did not fully prevent stent dysfunction due to reflux, further investigation is warranted.

Endoscopic Therapies for Chronic Pancreatitis

Chronic pancreatitis is a fibroinflammatory disease of the pancreas leading to varying degrees of endocrine and exocrine dysfunction. Treatment options are generally designed to control the pain of chronic pancreatitis, and endoscopic therapy is one of the main treatment modalities. Herein, we describe the endoscopic management of pancreatic duct calculi and strictures, entrapment of the intrapancreatic bile duct, celiac plexus interventions, and drainage of pancreatic pseudocysts.

Fabrication of a silver particle-integrated silicone polymer-covered metal stent against sludge and biofilm formation and stent-induced tissue inflammation

To reduce tissue or tumor ingrowth, covered self-expandable metal stents (SEMSs) have been developed. The effectiveness of covered SEMSs may be attenuated by sludge or stone formation or by stent clogging due to the formation of biofilm on the covering membrane. In this study, we tested the hypothesis that a silicone membrane containing silver particles (Ag-P) would prevent sludge and biofilm formation on the covered SEMS. In vitro, the Ag-P-integrated silicone polymer-covered membrane exhibited sustained antibacterial activity, and there was no definite release of silver ions from the Ag-P-integrated silicone polymer membrane at any time point. Using a porcine stent model, in vivo analysis demonstrated that the Ag-P-integrated silicone polymer-covered SEMS reduced the thickness of the biofilm and the quantity of sludge formed, compared with a conventional silicone-covered SEMS. In vivo, the release of silver ions from an Ag-P-integrated silicone polymer-covered SEMS was not detected in porcine serum. The Ag-P-integrated silicone polymer-covered SEMS also resulted in significantly less stent-related bile duct and subepithelium tissue inflammation than a conventional silicone polymer-covered SEMS. Therefore, the Ag-P-integrated silicone polymer-covered SEMS reduced sludge and biofilm formation and stent-induced pathological changes in tissue. This novel SEMS may prolong the stent patency in clinical application.