Endoscopic stenting for palliation of malignant biliary obstruction

Partial Stent-in-Stent Method with an Uncovered Self-Expandable Metallic Stent for Unresectable Malignant Hilar Bile Duct Obstruction

(1) Background: There is controversy regarding stent placement for unresectable malignant hilar biliary obstruction (UMHBO). We mainly use the partial stent-in-stent (PSIS) method with an uncovered self-expandable metallic stent (UCSEMS) based on the drainage area and patency period. In this study, we investigated the usefulness and safety of the PSIS method. (2) Methods: In total, 59 patients who underwent the PSIS method for UMHBO at our hospital were included in the study. The technical success rate, clinical success rate, time to recurrent biliary obstruction (TRBO) and overall survival (OS) from the first placement, factors affecting TRBO and OS, and early complications within 30 days after the procedure were evaluated retrospectively. (3) Results: The technical and clinical success rates were 100% and 96.6%, respectively, with a TRBO of 121 days [95% confidence interval: 82-231] and an OS of 194 days [95% confidence interval: 113-305] after the first placement. Early complications occurred in nine patients (15.3%), including five cases of cholangitis, three cases of pancreatitis, and one case of cholecystitis. (4) Conclusions: The PSIS method for UMHBO is safe and useful with high technical and clinical success rates.

Prevention of pancreatitis after stent implantation for distal malignant biliary strictures: systematic review and meta-analysis

INTRODUCTION

Biliary stent placement remains a palliative treatment for patients with unresectable distal malignant biliary strictures (DMBS). The incidence of post-ERCP-pancreatitis (PEP) significantly increases in patients receiving fully covered self-expandable metal stents (FCSEMS) who undergo endoscopic retrograde cholangiopancreatography (ERCP).

AREAS COVERED

This review provides an overview of prevention of PEP after stent implantation for DMBSs. The following operational variables were evaluated: (1) stent type (plastic or metal stent); (2) stent location (above or across the sphincter of Oddi); (3) prophylactic pancreatic duct stent placement; (4) endoscopic sphincterotomy (EST). PubMed, EMBASE, and Cochrane database were searched to identify eligible studies up to October 2021. The odds ratio (OR) with 95% confidence intervals (CI) were pooled using fixed- or random- effects models.

EXPERT OPINION

1. PEP occurs more frequently in DMBS patients with self-expandable metal stents (SEMS) compared to that plastic stent (PS). 2. The PEP incidence is higher in covered stents than that in uncovered self-expandable metal stents (USEMS), but not significantly. 3. PEP incidence increases in patients receiving transpapillary FCSEMS placement, particularly when there is an absence of pancreatic duct dilation, and prophylactic pancreatic stenting is recommended for these patients. 4. Limited studies with small sample indicate that there is no significant difference in PEP incidence between transpapillary and suprapapillary stents placement for DMBS. 5. Limited studies indicate that EST does not significantly affect the incidence of pancreatitis in DMBS patients.

Retained biliary plastic stents - lest we forget

Prolonged indwelling of endoscopically placed biliary plastic stents may lead to complications. We conducted a retrospective analysis of patients who underwent endoscopic retrograde cholangio-pancreaticography (ERCP) at our centre in 2017 and were noted to have retained biliary plastic stents ( > 3 months after an index ERCP). A total of 127 patients had previously placed biliary plastic stents, out of which 45 (35.4%) were retained. The median age of the latter was 52 years (range = 22-79 years) with 27 (60%) patients being men. The median duration of the retained stents was 144 days (range = 94-3292 days). The majority of the patients were asymptomatic. However, 9 (20%) patients had cholangitis, 2 (4.4%) had choledocholithiasis, 2 (4.4%) had cholangitic abscess and 1 (2.2%) developed septicaemia. Fortunately, all these complications could be managed medically and endoscopically. Retention of biliary plastic stents is a problem often overlooked and underestimated in clinical practice. Various measures need to be instituted to create awareness of this entity to prevent undesirable outcomes.

Endoscopic Drainage of >50% of Liver in Malignant Hilar Biliary Obstruction Using Metallic or Fenestrated Plastic Stents

OBJECTIVES

Endoscopic drainage of complex hilar tumors has generally resulted in poor outcomes. Drainage of >50% of liver volume has been proposed as optimal, but not evaluated using long multifenestrated plastic stents (MFPS) or self-expanding metal stents (SEMS). We evaluated outcomes of endoscopic drainage of malignant hilar strictures using optimal strategy and stents, and determined factors associated with stent patency, survival, and complications.

METHODS

Cross-sectional study was conducted at an academic center over 5 years. MFPS (10 French or 8.5 French) or open-cell SEMS were used for palliation of unresectable malignant hilar strictures, with imaging-targeted drainage of as many sectors as needed to drain >50% of viable liver volume. Risk factors were evaluated using regression analysis. The cumulative risk was assessed using Kaplan-Meier analysis.

RESULTS

77 patients with malignant hilar biliary strictures (median Bismuth IV) underwent targeted stenting (41 MFPS and 36 SEMS). Comparing MFPS vs. SEMS, technical success (95.1 vs. 97.2%, P=0.64), clinical success (75.6 vs. 83.3%, P=0.40), frequency of multiple stents (23/41 vs. 25/36, P=0.19), survival and adverse events were similar, but stent patency was significantly shorter (P<0.0001). Factors associated with survival were Karnofsky score and serum bilirubin level at presentation. Outcomes were independent of Bismuth class with acceptable results in Bismuth III and IV.

CONCLUSIONS

Endoscopic biliary drainage with MFPS or open-cell SEMS targeting >50% of viable liver resulted in effective palliation in patients with complex malignant hilar biliary strictures. Patency was shorter in the MFPS group, but similar survival and complications were found when comparing MFPS and SEMS group.

Endoscopic Palliation of Pancreatic Cancer

OPINION STATEMENT

Pancreas cancer is a fourth-leading cause of cancer death in the USA and its incidence is rising as the population is aging. The majority of patients present at an advanced stage due to the silent nature of the disease and treatment have focused more on palliation than curative intent. Gastroenterologists have become integral in the multidisciplinary care of these patients with a focus on providing endoscopic palliation of pancreas cancer. The three most common areas that gastroenterologists palliate endoscopically are biliary obstruction, cancer-related pain, and gastric outlet obstruction. To palliate biliary obstruction, the procedure of choice is to perform endoscopic retrograde cholangiopancreatography (ERCP) with biliary stent placement. We tend to place covered self-expandable metal stents (SEMS) due to their longer patency and removability unless the patient has resectable disease. Pancreas cancer pain is a result of tumor infiltration of the celiac plexus and can be severe and poorly responsive to narcotics. To improve pain control, neurolysis of the celiac plexus has been performed for decades. Since 1996, neurolysis of the celiac area has been performed endoscopically by Endoscopic Ultrasound-Guided Celiac Plexus Neurolysis. This has proven to be as safe and effective as traditional non-endoscopic methods and has allowed the patients to decrease their narcotic use and improve their pain control. This should be done early on in the course of the disease to have maximal effect. Gastric outlet obstruction (GOO) occurs in approximately 15-20% of patients with pancreas cancer. Endoscopic palliation of GOO can be performed by placing uncovered metal enteral stents across the obstruction. This procedure has proven to be very effective in patients who have a short life expectancy (less than two to 6 months) while surgical bypass should be considered for patients with longer life expectancies because it offers better long-term symptom relief. This chapter will review the current literature, latest advancements, and optimal techniques for endoscopic palliation of pancreatic cancer.

Self-expandable metal stents versus plastic stents for malignant biliary obstruction: a meta-analysis

BACKGROUND

Malignant biliary obstruction frequently portends a poor prognosis. Palliative treatment with stenting is often required to alleviate symptoms and potentially prevent adverse events.

OBJECTIVES

The aims of our study were (1) to evaluate the clinical difference between self-expandable metal stents (SEMSs) and plastic stents (PSs) in both hilar and distal malignant biliary obstruction on occlusion rate and 30-day mortality rate (primary outcomes) and stent insertion success rate, therapeutic failure, reintervention rate, and adverse events (secondary outcomes); (2) to compare unilateral stenting with bilateral stenting in hilar malignant obstruction in terms of occlusion rate and 30-day mortality rate (primary outcomes) and insertion success rate, therapeutic failure, and adverse events (secondary outcomes).

METHODS

PubMed, Embase, and Cochrane databases were searched for studies that provided data about malignant biliary obstruction and stent therapy. We included randomized, controlled trials (RCT), prospective observational cohort, and retrospective case-control studies. The quality of each included RCT study was assessed by the Jadad scale. Mantel-Haenszel odds ratios (ORs) and mean differences were calculated by using a random-effects model.

RESULTS

Nineteen studies involving 1989 patients (1045 SEMSs and 944 PSs) were included for the comparison of SEMSs and PSs. We also included 7 studies that compared unilateral with bilateral stenting involving 634 patients (346 unilateral and 268 bilateral). Our meta-analysis confirmed that SEMSs are associated with a statistically significant lower risk of occlusion compared with PSs in the short term (OR 0.27; 95% confidence interval [CI], 0.13-0.60) and long term (OR 0.38; 95% CI, 0.28-0.53). SEMSs had a lower 30-day occlusion rate than PSs in both hilar malignant obstruction (OR 0.16; 95% CI, 0.04-0.62) and distal malignant obstruction (OR 0.36; 95% CI, 0.14-0.93). SEMSs had a lower long-term occlusion rate compared with PSs in hilar malignant obstruction (OR 0.28; 95% CI, 0.19-0.39) and distal malignant obstruction (OR 0.42; 95% CI, 0.27-0.64). The 30-day mortality rate was similar with SEMSs and PSs (OR 0.74; 95% CI, 0.47-1.17). Therapeutic failure was more likely when using PSs (13%) compared with SEMSs (7%) (OR 0.43; 95% CI, 0.27-0.67). SEMSs required fewer reinterventions compared with PSs (mean difference, -0.49; 95% CI, -0.8 to -0.19). The incidence of cholangitis was statistically lower with SEMSs (8% vs 21%) (OR 0.41; 95% CI, 0.22-0.76). Bilateral stenting for hilar obstruction was not associated with a lower obstruction rate than unilateral stenting (OR 1.49; 95% CI, 0.77-2.89) or a lower 30-day mortality rate (OR 0.73; 95% CI, 0.29-1.79). There was no statistical difference in therapeutic failure (OR 1.47; 95% CI, 0.77-2.89) or cholangitis incidence (OR 0.61; 95% CI, 0.27-1.38).

CONCLUSION

SEMSs are associated with a statistically significantly lower occlusion rate, less therapeutic failure, less need for reintervention, and lower cholangitis incidence. There was no statistically significant difference in occlusion rate, therapeutic failure, and cholangitis incidence with bilateral stenting. Guideline recommendations may need to be modified to reflect clear and compelling data demonstrating the benefit of SEMSs in patients with malignant biliary obstruction. Bilateral stenting should be avoided because it has no benefit over unilateral stenting in terms of occlusion rate or therapeutic failure.

Biliary stenting in advanced malignancy: an analysis of predictive factors for survival

Purpose

Stenting of the biliary tree is a common palliative procedure to relieve obstructive jaundice in advanced malignancy. Although effective in relief of biliary obstruction and palliation of symptoms, little information is available on predictive factors for survival post-procedure. This retrospective study sought to assess factors influencing post-procedure survival in cancer patients after biliary stenting.

Methods

Case notes of all patients from a regional academic cancer center, who underwent biliary stenting for obstructive jaundice related to malignancy during 2008 and 2009 were reviewed. We collected epidemiological, biochemical, treatment and survival data on all patients. We used Kaplan–Meyer analysis to assess survival from day of first biliary stenting (adjusted for cancer types), and the Cox proportional hazards model for univariate and multivariate analysis.

Results

One hundred and ninety-four patients were included in the final analysis. Most cases were related to pancreatic cancer or cholangiocarcinoma (89 and 46 cases respectively). Median survival for all patients was 143 days. In multivariate analysis serum albumin ≥34 g/L at the time of procedure (hazard ratio 0.573; 95% confidence interval 0.424–0.773, P<0.001) and chemotherapy post-stent (hazard ratio 0.636; 95% confidence interval 0.455–0.889, P=0.008) were two independent prognostic factors predicting a better survival post-stenting. The 30 day mortality post-procedure in the 194 patients was 12%.

Conclusion

This study suggests that stenting of the biliary tree in cases of malignant obstruction allows durable palliation of symptoms even in cases where further active chemotherapy treatment is not possible. However, the better outcome observed in patients with albumin ≥34 g/L and those receiving chemotherapy post-stent requires further validation.

Endoscopic management of biliary disorders: diagnostic and therapeutic

The use of peroral endoscopy in the diagnosis of and therapy for biliary disorders has evolved immensely since the introduction of flexible fiberoptic endoscopes more than 50 years ago. Endoscopic retrograde cholangiopancreatography was introduced approximately a decade after flexible upper endoscopy and has evolved from a purely diagnostic procedure to almost exclusively a therapeutic procedure for managing biliary tract disorders. Endoscopic ultrasound, which continues to be a procedure of high diagnostic yield, is becoming a therapeutic modality for management of biliary diseases. This article discusses the diagnostic and therapeutic aspects of endoscopic retrograde cholangiopancreatography and endoscopic ultrasound for evaluation and treatment of biliary diseases.

Randomized trial in malignant biliary obstruction: plastic vs partially covered metal stents

AIM

To compare efficacy and complications of partially covered self-expandable metal stent (pcSEMS) to plastic stent (PS) in patients treated for malignant, infrahilar biliary obstruction.

METHODS

Multicenter prospective randomized clinical trial with treatment allocation to a pcWallstent(®) (SEMS) or a 10 French PS. Palliative patients aged ≥ 18, for infrahilar malignant biliary obstruction and a Karnofsky performance scale index > 60% from 6 participating North American university centers. Primary endpoint was time to stent failure, with secondary outcomes of death, adverse events, Karnofsky performance score and short-form-36 scale administered on a three-monthly basis for up to 2 years. Survival analyses were performed for stent failure and death, with Cox proportional hazards regression models to determine significant predictive characteristics.

RESULTS

Eighty-five patients were accrued over 37 mo, 42 were randomized to the SEMS group and 83 patients were available for analyses. Time to stent failure was 385.3 ± 52.5 d in the SEMS and 153.3 ± 19.8 d in the PS group, P = 0.006. Time to death did not differ between groups (192.3 ± 23.4 d for SEMS vs 211.5 ± 28.0 d for PS, P = 0.70). The only significant predictor was treatment allocation, relating to the time to stent failure (P = 0.01). Amongst other measured outcomes, only cholangitis differed, being more common in the PS group (4.9% vs 24.5%, P = 0.029). The small number of patients in follow-up limits longitudinal assessments of performance and quality of life. From an initially planned 120 patients, only 85 patients were recruited.

CONCLUSION

Partially covered SEMS result in a longer duration till stent failure without increased complication rates, yet without accompanying measurable benefits in survival, performance, or quality of life.

Biliary stenting in patients with malignant biliary obstruction: comparison of double layer, plastic and metal stents

BACKGROUND AND AIM

The double layer stent (DLS) has a unique design and has been used for palliation of malignant biliary obstruction, but literature on this stent is limited. Our aim was to compare plastic (PS), DLS and metal stents (MS) in terms of complication rates, time to occlusion, and patency rate in patients with malignant biliary obstruction (MBO).

METHODS

A retrospective review of stents placed for MBO at our institution in the period between January 2009 and April 2011 was conducted. A total of 114 stents were identified, of which 44 were MS (39 %), 37 DLS (32 %), and 33 PS (29 %). A stent was considered occluded when an unplanned stent removal or intervention occurred due to clinical suspicion of biliary obstruction.

RESULTS

Stents remained patent for 95 days (range 7-359 days) in the DLS group and 59 days (range 7-228 days) in the PS group (P = 0.014) and 128.7 days (range 4-602 days) in the metal stent group. Twenty-seven percent (n = 9) of PS occluded after a mean of 60 days while 16 % (n = 7) of MS occluded after a mean of 87 days and 5 % (n = 2) of DLS occluded after a mean of 85 days (DLS vs. PS P = 0.012, DLS vs. MS P = 0.13, MS vs. PS P = 0.22).

CONCLUSIONS

DLS are superior to PS in patients with MBO and appear to be comparable to MS. MS had a longer patency rate but were comparable to DLS in early and late complications. We speculate that the less expensive DLS may be a cost effective alternative in the palliation of MBO.

Clinical advantages of a metal stent with an S-shaped anti-reflux valve in malignant biliary obstruction

BACKGROUND AND AIM

Transpapillary stent insertion is the standard treatment for palliating malignant biliary obstruction. However, luminal occlusion often occurs due to sludge formation, tumor ingrowth, or tumor overgrowth. Currently, influx of duodenal contents by duodenobiliary reflux is considered a mechanism of stent obstruction. The aim of the present study was to evaluate the efficacy and safety of a metal stent with an anti-reflux valve in distal malignant biliary obstruction.

METHODS

Thirty-two patients diagnosed with unresectable malignant biliary obstruction were enrolled. This trial was conducted at two tertiary hospitals in Korea from June 2009 to June 2011. An uncovered metal stent (M.I.Tech) with an S-type anti-reflux valve was placed.

RESULTS

A total of 32 patients were enrolled. The technical success rate of stent insertion was 100%. The median duration of stent patency was 14.4 months. Stent occlusion occurred in 11 cases, which was caused by sludge formation in six cases, tumor ingrowth in four cases, and migration of the stent membrane in one case. During the follow-up period, there were no episodes of ascending cholangitis, acute pancreatitis, or bleeding.

CONCLUSIONS

The new metal stent with an S-shaped anti-reflux valve demonstrated a relatively long duration of stent patency. This was attributable to reductions in duodenobiliary reflux by the anti-reflux valve. Also, the stent with an S-shaped anti-reflux valve is technically feasible and very safe. However, further prospective, randomized comparison studies of stents with anti-reflux valves and conventional stents are needed to evaluate the duration of stent patency.

Pancreatic and biliary stents

Biliary and pancreatic stents are used in a variety of benign and malignant conditions including strictures and leaks and in the prevention of post-ERCP pancreatitis.Both plastic and metal stents are safe, effective, and easy to use. SEMSs have traditionally been used for inoperable malignant disease. Covered SEMSs are now being evaluated for use in benign disease. Increasing the duration of patency of both plastic and metal stents remains an important area for future research.

Bile culture and susceptibility testing of malignant biliary obstruction via PTBD

PURPOSE

To assess the information obtained by bile culture and susceptibility testing for malignant biliary obstruction by a retrospective one-center study.

METHODS

A total of 694 patients with malignant biliary obstruction received percutaneous transhepatic biliary drainage during the period July 2003 to September 2010, and subsequently, bile specimens were collected during the procedure. Among the 694 patients, 485 were men and 209 were women, ranging in age from 38 to 78 years (mean age 62 years).

RESULTS

A total of 42.9% patients had a positive bile culture (298 of 694). Further, 57 species of microorganisms and 342 strains were identified; gram-positive bacteria accounted for 50.9% (174 of 342) and gram-negative bacteria accounted for 41.5% (142 of 342) of these strains. No anaerobes were obtained by culture during this study. The most common microorganisms were Enterococcus faecalis (41 of 342, 11.9%), Escherichia coli (34 of 342, 9.9%), Klebsiella pneumoniae (28 of 342, 8.2%), Staphylococcus epidermidis (19 of 342, 5.5%), Enterococcus (18 of 342, 5.3%), and Enterobacter cloacae (16 of 342, 4.7%). The percentage of β-lactamase-producing gram-positive bacteria was 27.6% (48 of 174), and the percentage of gram-negative bacteria was 19.7% (28 of 142). The percentage of enzyme-producing Escherichia coli was 61.7% (21 of 34).

CONCLUSION

The bile cultures in malignant biliary obstruction are different from those in the Tokyo Guidelines and other benign biliary obstruction researches, which indicates that a different antibacterial therapy should be applied. Thus, knowledge of the antimicrobial susceptibility data could aid in the better use of antibiotics for the empirical therapy of biliary infection combined with malignant biliary obstruction.

Plastic biliary stents for malignant biliary diseases

Plastic biliary endoprostheses have not changed much since their introduction more than 3 decades ago. Although their use has been challenged by the introduction of metal stents, plastic stents still remain commonly used. Much work has been done to improve the problem of stent obstruction but without substantial clinical success. In this review, the authors discuss the history of plastic biliary stent development and the current use of plastic stents for malignant biliary diseases.