Cost utility of ERCP-based modalities for the diagnosis of cholangiocarcinoma in primary sclerosing cholangitis

Chinese national clinical practice guideline on diagnosis and treatment of biliary tract cancers

BACKGROUND

Biliary tract carcinoma (BTC) is relatively rare and comprises a spectrum of invasive tumors arising from the biliary tree. The prognosis is extremely poor. The incidence of BTC is relatively high in Asian countries, and a high number of cases are diagnosed annually in China owing to the large population. Therefore, it is necessary to clarify the epidemiology and high-risk factors for BTC in China. The signs associated with BTC are complex, often require collaborative treatment from surgeons, endoscopists, oncologists, and radiation therapists. Thus, it is necessary to develop a comprehensive Chinese guideline for BTC.

METHODS

This clinical practice guideline (CPG) was developed following the process recommended by the World Health Organization. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess the certainty of evidence and make recommendations. The full CPG report was reviewed by external guideline methodologists and clinicians with no direct involvement in the development of this CPG. Two guideline reporting checklists have been adhered to: Appraisal of Guidelines for Research and Evaluation (AGREE) and Reporting Items for practice Guidelines in Healthcare (RIGHT).

RESULTS

The guideline development group, which comprised 85 multidisciplinary clinical experts across China. After a controversies conference, 17 clinical questions concerning the prevention, diagnosis, and treatment of BTC were proposed. Additionally, detailed descriptions of the surgical principles, perioperative management, chemotherapy, immunotherapy, targeted therapy, radiotherapy, and endoscopic management were proposed.

CONCLUSIONS

The guideline development group created a comprehensive Chinese guideline for the diagnosis and treatment of BTC, covering various aspects of epidemiology, diagnosis, and treatment. The 17 clinical questions have important reference value for the management of BTC.

Assessing the impact of center volume on the cost-effectiveness of centralizing ERCP

BACKGROUND AND AIMS

ERCP is a complex endoscopic procedure in which the center's procedure volume influences outcomes. With the increasing healthcare expenses and limited resources, promoting cost-effective care becomes essential for healthcare provision. This study was a cost-effectiveness analysis to evaluate the hypothesis that high-volume (HV) centers perform ERCP with higher quality at lower costs than low-volume (LV) centers.

METHODS

A baseline case compared the current distribution of ERCPs among HV and LV centers with a hypothetical scenario in which all ERCPs are performed at HV centers. A cost-effectiveness analysis was constructed, followed by 1- and 2-way sensitivity analyses, and probabilistic sensitivity analysis using Monte Carlo simulations.

RESULTS

In the baseline case, the incremental cost-effectiveness ratio was -$151,270 per year, due to the hypothetical scenario's lower costs and slightly higher quality-adjusted life years. The model was most sensitive to changes in transportation costs (109.34%), probability of significant adverse events (AEs) after successful ERCP at LV centers (42.12%), utility after ERCP with significant AEs (30.10%), and probability of significant AEs after successful ERCP at HV centers (23.53%); only transportation costs above $3655 changed the study outcome, however. The current ERCP distribution would only be cost-effective if LV centers achieved higher success (≥92.4% vs 89.3%), with much lower significant AEs (≤.5% vs 6.7%). The study's main findings remained unchanged while combining all model parameters in the probabilistic sensitivity analysis.

CONCLUSIONS

Our findings show that HV centers have high-performance rates at lower costs, raising the need to consider the principle of centralization of ERCPs into HV centers to improve the quality of care.

Application of AI on cholangiocarcinoma

Cholangiocarcinoma, classified as intrahepatic, perihilar, and extrahepatic, is considered a deadly malignancy of the hepatobiliary system. Most cases of cholangiocarcinoma are asymptomatic. Therefore, early detection of cholangiocarcinoma is significant but still challenging. The routine screening of a tumor lacks specificity and accuracy. With the application of AI, high-risk patients can be easily found by analyzing their clinical characteristics, serum biomarkers, and medical images. Moreover, AI can be used to predict the prognosis including recurrence risk and metastasis. Although they have some limitations, AI algorithms will still significantly improve many aspects of cholangiocarcinoma in the medical field with the development of computing power and technology.

Endoscopic procedures in hepatology: Current trends and new developments

Gastrointestinal endoscopy has long been a reliable backbone in the diagnosis and management of hepatobilary disorders and their complications. However, with evolving non-invasive testing, personalised medicine has reframed the utility and necessity of endoscopic screening. Conversely, the growing interest and use of endoscopic ultrasound (EUS) and advanced endoscopy within gastrointestinal units has also opened novel diagnostic and therapeutic avenues for patients with various hepatobiliary diseases. The integration of "advanced endoscopy" within the practice of hepatology is nowadays referred to as "endo-hepatology". In essence, endo-hepatology consists of two pillars: one focusing primarily on disorders of the liver parenchyma, vascular disorders, and portal hypertension, which is mainly captured via EUS, while the other targets the hepatobiliary tract via endoscopic retrograde cholangiopancreatography and advanced imaging. Applications under the umbrella of endo-hepatology include, amongst others, EUS-guided liver biopsy, EUS-guided portal pressure gradient measurement, coil and glue embolisation of gastric varices as well as cholangioscopy. As such endo-hepatology could become an attractive concept wherein advanced endoscopy might reinforce the medical management of patients with hepatobiliary disorders and their complications after initial basic work-up. In this review, we discuss current trends and future developments within endo-hepatology and the remaining hurdles to overcome.

American Society for Gastrointestinal Endoscopy guideline on the role of endoscopy in the diagnosis of malignancy in biliary strictures of undetermined etiology: summary and recommendations

This clinical practice guideline from the American Society for Gastrointestinal Endoscopy provides an evidence-based approach for the diagnosis of malignancy in patients with biliary strictures of undetermined etiology. This document was developed using the Grading of Recommendations Assessment, Development and Evaluation framework and addresses the role of fluoroscopic-guided biopsy sampling, brush cytology, cholangioscopy, and EUS in the diagnosis of malignancy in patients with biliary strictures. In the endoscopic workup of these patients, we suggest the use of fluoroscopic-guided biopsy sampling in addition to brush cytology over brush cytology alone, especially for hilar strictures. We suggest the use of cholangioscopic and EUS-guided biopsy sampling especially for patients who undergo nondiagnostic sampling, cholangioscopic biopsy sampling for nondistal strictures and EUS-guided biopsy sampling distal strictures or those with suspected spread to surrounding lymph nodes and other structures.

American Society for Gastrointestinal Endoscopy guideline on role of endoscopy in the diagnosis of malignancy in biliary strictures of undetermined etiology: methodology and review of evidence

Biliary strictures of undetermined etiology pose a diagnostic challenge for endoscopists. Despite advances in technology, diagnosing malignancy in biliary strictures often requires multiple procedures. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework was used to rigorously review and synthesize the available literature on strategies used to diagnose undetermined biliary strictures. Using a systematic review and meta-analysis of each diagnostic modality, including fluoroscopic-guided biopsy sampling, brush cytology, cholangioscopy, and EUS-guided FNA or fine-needle biopsy sampling, the American Society for Gastrointestinal Endoscopy Standards of Practice Committee provides this guideline on modalities used to diagnose biliary strictures of undetermined etiology. This document summarizes the methods used in the GRADE analysis to make recommendations, whereas the accompanying article subtitled "Summary and Recommendations" contains a concise summary of our findings and final recommendations.

Clinical approach to indeterminate biliary strictures: Clinical presentation, diagnosis, and workup

Despite advances in cross-sectional imaging and endoscopic technology, bile duct strictures remain a challenging clinical entity. It is crucial to make an early determination of benign or malignant nature of biliary strictures. Early diagnosis not only helps with further management but also minimizes mortality and morbidity associated with delayed diagnosis. Conventional imaging and endoscopic techniques, particularly endoscopic retrograde cholangiopancreatography (ERCP) and tissue sampling techniques play a key in establishing a diagnosis. Indeterminate biliary strictures (IDBSs) have no definite mass on imaging or absolute histopathological diagnosis and often warrant utilization of multiple diagnostics to ascertain an etiology. In this review, we discuss possible etiologies, clinical presentation, diagnosis, and management of IDBSs. Based on available data and expert opinion, we depict an evidence based diagnostic algorithm for management of IDBSs. Areas of focus include use of traditional tissue sampling techniques such as ERCP with brush cytology, intraductal biopsies, fluorescence in situ hybridization and flow cytometry. We also describe the role of endoscopic ultrasound (EUS)-guided fine needle aspiration and biopsies, cholangioscopy, confocal laser endomicroscopy, and intraductal EUS in management of IDBSs.

Fully Covered Self-expanding Stents are Cost-effective at Remediating Biliary Strictures in Patients With Chronic Pancreatitis

Benign biliary strictures (BBS) develop in up to 10% to 30% of patients with chronic pancreatitis (CP).¹ Endoscopic endoprosthetics via endoscopic retrograde cholangiopancreatography (ERCP) has become the standard of care for remediating these strictures. Seventy percent to eighty percent of these strictures resolve with sequential or concurrent placement of multiple plastic stents (MPS).^1,2 More recently, placement of fully covered self-expanding metal stents (FCSEMS) have been shown to have similar outcomes as MPS.^3-6 FCSEMS provide a larger radial diameter and require fewer procedures, but may have drawbacks, including a higher risk of migration, cholecystitis, delamination, and tissue ingrowth. A recent study demonstrated that FCSEMS with a 12-month indwell had similar outcomes to MPS with fewer ERCP needed.⁷ However, the cost-effectiveness of either strategy for managing BBS has not been assessed previously nor has the impact of additional reimbursement to cover the cost of FCSEMS on the cost-effectiveness of FCSEMS utilization.

A Prospective Cohort Study Evaluating PAN-PROMISE, a Patient-reported Outcome Measure to Detect Post-ERCP Morbidity

BACKGROUND & AIMS

The Cotton Consensus (CC) criteria for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) may not capture post-ERCP morbidity. PAN-PROMISE, a patient-reported outcome measure (PROM), was developed to quantify acute pancreatitis-related morbidity. This study aims to determine the value of PAN-PROMISE in independently defining ERCP-related morbidity.

METHODS

We conducted a prospective cohort study of patients undergoing ERCP at 2 academic centers from September 2021 to August 2022. We administered PAN-PROMISE and assessed quality of life and work productivity at baseline, 48 to 72 hours, 7 days, and 30 days following ERCP. PEP was defined by a 3-physician committee using the CC criteria. We defined high morbidity following ERCP (elevated PROM) by an increase of PAN-PROMISE score of >7 at 7 days post-procedure. The McNemar test assessed discordance between PEP and elevated-PROM.

RESULTS

A total of 679 patients were enrolled. Choledocholithiasis (30%) and malignant biliary obstruction (29%) were the main indications for ERCP. Thirty-two patients (4.7%) developed PEP. One hundred forty-seven patients (21.6%) had an elevated PROM, whereas only 20 of them (13.4%) had PEP by the CC criteria (P < .001 for discordance). An elevated PROM strongly correlated with lower physical quality of life and increased direct and indirect health care costs ($80 and $25 per point increase in PAN-PROMISE, respectively). Patients with pancreatic cancer (odds ratio, 4.52; 95% confidence interval, 1.68-10.74) and primary sclerosing cholangitis (odds ratio, 1.79; 95% confidence interval, 1.29-2.45) had the highest odds of elevated PROM.

CONCLUSIONS

A substantial number of patients experience significant morbidity after ERCP despite not developing PEP or other adverse events. Future studies are needed to characterize better the reasons behind this increase in symptoms and potential interventions to reduce the symptom burden post-ERCP.

CLINICALTRIALS

gov number, NCT05310409.

The Role of Cholangioscopy and EUS in the Evaluation of Indeterminate Biliary Strictures

Bile duct stenosis continues to present a diagnostic dilemma for clinicians. It is important to establish the benign or malignant nature of the stricture early in order to avoid any unnecessary delay in medical treatment or surgery. Tissue acquisition for histological diagnosis is particularly crucial when the initial diagnostic work up is inconclusive. The diagnostic yield from the conventional endoscopic retrograde cholangiopancreatography (ERCP) with brushing and biopsy is suboptimal. Patients with indeterminate biliary strictures (IDBSs) often require a multi-disciplinary diagnostic approach and additional endoscopic evaluation, including cholangioscopy and endoscopic ultrasound, before a final diagnosis can be reached. In this article, we discuss the recent endoscopic advancements in the diagnosis of biliary stricture with a focus on the roles of cholangioscopy and endoscopic ultrasound (EUS).

Impact of trimodality sampling on detection of malignant biliary strictures compared with patients with primary sclerosing cholangitis

BACKGROUND AND AIMS

Malignant biliary strictures can be difficult to diagnose, with up to 20% considered indeterminate after initial tissue sampling. This study aimed to determine the performance characteristics of transpapillary biopsy sampling (TPB) and fluorescence in situ hybridization (FISH) in isolation or in combination with standard brush cytology (BC) in patients who received trimodality sampling for biliary strictures.

METHODS

This single-center retrospective cohort study included patients with biliary strictures undergoing ERCP with trimodality sampling between September 2014 and April 2019. Performance characteristics for each diagnostic test alone and in combination were calculated.

RESULTS

Two hundred four patients underwent trimodality biliary sampling, including 104 (51.0%) with malignancy. The diagnostic sensitivity for malignancy with BC (17.3%) significantly improved with dual modality (BC+FISH, 58.7%; BC+TPB, 40.4%) or trimodality sampling (68.3%; P < .001 for all comparisons). Trimodality sampling improved diagnostic sensitivity for malignancy compared with BC+FISH (P = .002) and BC+TPB (P < .001). There was no statistically significant difference in the sensitivity of trimodality sampling in detecting cholangiocarcinoma (79.7%) compared with pancreatic cancer (62.5%; P = .1). Among 57 patients with primary sclerosing cholangitis (PSC), the sensitivity of detecting biliary malignancy (n = 20) was 20% for BC and significantly improved with the addition of FISH (80%; P < .001) but not with TPB (35.0%; P = .25). Trimodality sampling did not further improve diagnostic sensitivity (85%) over BC+FISH (80%) for malignancy in the setting of PSC (P = 1).

CONCLUSIONS

Trimodality sampling improves the diagnostic sensitivity for the detection of malignant biliary strictures with no significant difference in sensitivity for cholangiocarcinoma compared with pancreatic cancer. However, in patients with PSC, trimodality sampling was not superior to BC+FISH.

A Cost-Effectiveness Analysis for Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis Prophylaxis in the United States

BACKGROUND & AIMS

Post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) is the most common adverse event after endoscopic retrograde cholangiopancreatography, and is responsible for substantial morbidity and health care expenditures of at least $200 million. Therapies for PEP prevention include pancreatic stent placement (PSP), rectal indomethacin, sublingual nitrates, and aggressive lactated Ringer's hydration. Our objective was to determine which PEP prophylactic strategies are cost effective.

METHODS

We developed 2 separate decision trees to evaluate PEP prophylactic strategies. The first, in high-risk patients, compared rectal indomethacin, PSP, PSP with indomethacin, sublingual nitrates, aggressive hydration with lactated Ringer's, and no prophylaxis. The second, in average-risk patients, compared rectal indomethacin, sublingual nitrates, aggressive hydration, and no prophylaxis. We used incidence rates, transition probabilities, and costs from publications and public data sources. Outcome measures were reported as incremental cost-effectiveness ratios, with a willingness-to-pay (WTP) threshold of $100,000/quality-adjusted life years (QALYs).

RESULTS

Compared with no prophylaxis, all strategies were cost effective at a WTP of $100,000 in preventing PEP in high-risk patients. When directly compared with each other, rectal indomethacin was the cost-effective strategy in high-risk patients ($31,589/QALYs). In average-risk patients, indomethacin and sublingual nitrates were cost effective at a WTP of $100,000/QALYs compared with no prophylaxis. When directly compared with each other, rectal indomethacin was the cost-effective strategy ($53,016/QALYs).

CONCLUSIONS

Rectal indomethacin was the cost-effective strategy for preventing PEP in both average-risk and high-risk patients undergoing endoscopic retrograde cholangiopancreatography. All strategies were cost effective when compared with no prophylaxis in high-risk patients, whereas all strategies except for aggressive hydration with lactated Ringer's were cost effective in average-risk patients. Further studies are needed to improve the utilization of PEP prevention strategies.

Stent versus Balloon Dilation for the Treatment of Dominant Strictures in Primary Sclerosing Cholangitis: A Systematic Review and Meta-Analysis

Background/Aims

The endoscopic management of primary sclerosing cholangitis (PSC)-associated dominant strictures remains challenging. This systematic review and meta-analysis aimed to compare balloon dilation and stent placement in the treatment of dominant strictures among PSC patients.

Methods

Literature searches on MEDLINE, EMBASE, Cochrane CENTRAL and Lilacs/Bireme were performed for studies published until December 2020. Measured outcomes included clinical efficacy, stricture recurrence, cumulative recurrencefree rate, transplant rate, 5-year survival rate, and adverse events (i.e., pancreatitis, cholangitis, bleeding, perforation and death).

Results

A total of 5 studies (n=467) were included. Based on pooled analyses, there were no differences in clinical efficacy (risk difference [RD], -0.13; 95% confidence interval [CI], -0.58 to 0.33; I²=93%) or transplant rates (RD, -0.09; 95% CI, -0.19 to 0.01; I²=0%); however, the risk of occurrence of adverse events was lower with balloon dilatation than with stent placement (RD,-0.34; 95% CI, -0.45 to -0.23; I²=61%). Among the types of adverse events reported, only the rates of cholangitis/bacteremia were significantly lower in balloon dilation patients (RD, -0.19; 95% CI, -0.25 to -0.13; I²=51%).

Conclusions

Compared to balloon dilation, stent placement for dominant strictures in PSC appeared to have higher complication rates without significant differences in efficacy.

Present and future role of endoscopic retrograde cholangiography in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a rare, inflammatory cholestatic liver disease that causes biliary strictures which can lead to secondary complications. About 30-50% of PSC patients develop dominant strictures (DS) in the biliary tree, which are both the cause of jaundice and bacterial cholangitis as well as predilection spots for development of neoplastic development. Cancer is the most common cause of death in PSC. A central concern is to distinguish malignant from benign strictures, which eventually is done by invasive methods to obtain a brush cytology or biopsy sample, in most cases via endoscopic retrograde cholangiography-pancreatography (ERCP). Since medical therapies, like ursodesoxycholic acid or immunosuppressive drugs have no proven effect, therapeutic ERCP has become the primary management strategy to improve symptoms and in some patients may slow down disease progression. This article aims at outlining the current and emerging methods in ERCP in PSC patients.

Italian Clinical Practice Guidelines on Cholangiocarcinoma - Part I: Classification, diagnosis and staging

Cholangiocarcinoma (CCA) is the second most common primary liver cancer, characterized by a poor prognosis and resistance to chemotherapeutics. The progressive increase in CCA incidence and mortality registered worldwide in the last two decades and the need to clarify various aspects of clinical management have prompted the Italian Association for the Study of the Liver (AISF) to commission the drafting of dedicated guidelines in collaboration with a group of Italian scientific societies. These guidelines have been formulated in accordance with the Italian National Institute of Health indications and developed by following the GRADE method and related advancements.

New Devices for Endoscopic Treatments in Gastroenterology: A Narrative Review

Endoscopy is in a period of continuous innovations in terms of image quality, endoscopes, post-processing software and lastly, application of Artificial Intelligence. Therapeutic boundaries have expanded, widening the grey zone between endoscopy and surgery, and increasing endoscopic approaches in clinical scenarios where, until a few years ago, surgery was the only option. New scopes and accessories have made it easier to access critical areas such as the biliary tree and the small bowel intestine. In the field of hepato-pancreato-biliary endoscopy (HPB), it is now possible to directly access the biliary ducts or cystic lesions though dedicated stents and scopes, rather than having to rely only on fluoroscopy and ultrasound, increasing the diagnostic and therapeutic options by applying a three-dimensional approach. This narrative review will give an overview of some of the most relevant emerging fields in luminal and HPB endoscopy, highlighting advantages and main limitations of the techniques, and providing considerations for future development.

Challenging biliary strictures: pathophysiological features, differential diagnosis, diagnostic algorithms, and new clinically relevant biomarkers - part 1

It is frequently challenging to make the correct diagnosis in patients with biliary strictures. This is particularly important as errors may have disastrous consequences. Benign-appearing strictures treated with stents may later be revealed to be malignant and unnecessary surgery for benign strictures carries a high morbidity rate. In the first part of the review, the essential information that clinicians need to know about diseases responsible for biliary strictures is presented, with a focus on the most recent data. Then, the characteristics and pitfalls of the methods used to make the diagnosis are summarized. These include serum biomarkers, imaging studies, and endoscopic modalities. As tissue diagnosis is the only 100% specific tool, it is described in detail, including techniques for tissue acquisition and their yields, how to prepare samples, and what to expect from the pathologist. Tricks to increase diagnostic yields are described. Clues are then presented for the differential diagnosis between primary and secondary sclerosing cholangitis, IgG4-related sclerosing cholangitis, cholangiocarcinoma, pancreatic cancer, autoimmune pancreatitis, and less frequent diseases. Finally, algorithms that will help to achieve the correct diagnosis are proposed.

Cholangioscopy Biopsies Improve Detection of Cholangiocarcinoma When Combined with Cytology and FISH, but Not in Patients with PSC

BACKGROUND AND AIMS

Single-operator cholangioscopy (SOC) has been suggested to be a cost-effective strategy for the detection of cholangiocarcinoma (CCA). The aim of this study is to compare the performance characteristics of SOC-guided biopsies and transpapillary biopsies with standard sampling techniques for the detection of CCA.

METHODS

A retrospective cohort study of patients undergoing SOC between 1/2007 and 10/2018 at a single academic center was performed. Demographic, procedural, and outcomes data were recorded and analyzed using STATA 14.0. Sensitivity comparison between diagnostic tests was performed using exact McNemar test exclusively among patients with CCA. Two-sided p value < 0.05 was considered statistically significant.

RESULTS

Ninety-two patients were included; 36 (39.1%) with primary sclerosing cholangitis (PSC), 41 (44.6%) with CCA, and median follow-up was 15.1 months. In the overall cohort, brush cytology demonstrated a sensitivity of 44.7% and increased with the addition of FISH (56.8%; p = 0.12), FISH with SOC-guided biopsy (71.4%; p = 0.03), and FISH with transpapillary biopsy (64.5%; p = 0.01). However, in patients with PSC, there was no significant improvement in sensitivity with the addition of SOC-guided biopsy or transpapillary biopsy in addition to FISH when compared to brush cytology. There was no difference in the rates of overall adverse events (14% vs. 23.2%; p = 0.27) or infection (3% vs. 4%; p = 0.83) in patients with and without PSC.

CONCLUSIONS

SOC-guided and transpapillary biopsies improve sensitivity for the detection of cholangiocarcinoma in combination with other ERCP-based techniques compared to brush cytology alone. However, while safe, these modalities do not significantly improve the sensitivity for the detection of malignancy in PSC patients.

Role of Peroral Cholangioscopy in the Diagnosis of Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is characterized by idiopathic biliary stricture followed by progressive cholestasis and fibrosis. When diagnosing PSC, its differentiation from other types of sclerosing cholangitis and cholangiocarcinoma is necessary. The cholangioscopic findings of PSC have not been investigated sufficiently. PSC and IgG4-related sclerosing cholangitis are difficult to distinguish by peroral cholangioscopy (POCS), but POCS is useful for excluding cholangiocarcinoma. POCS findings vary according to the condition and stage of disease. In the active phase, findings such as mucosal erythema, ulceration, fibrinous white exudate, and an irregular surface are observed and may reflect strong inflammation in the biliary epithelium. On the other hand, findings such as scarring, pseudodiverticula, and bile duct stenosis appear in the chronic phase and may reflect fibrosis and stenosis resulting from repeated inflammation. Observation of inside the bile duct by POCS might confirm the current PSC activity. Because POCS offers not only information regarding the diagnosis of PSC and PSC-associated cholangiocarcinoma but also the current statuses of biliary inflammation and stenosis, POCS could significantly contribute to the diagnosis and treatment of PSC once the characteristic findings of PSC are confirmed by future studies.

The Expansion of Cholangioscopy: Established and Investigational Uses of SpyGlass in Biliary and Pancreatic Disorders

Direct visualization of bile and pancreatic duct pathology is proving to be beneficial in patients where previous techniques have failed. Recent advancements in technology and the development of the SpyGlass system have led to an increased use of cholangioscopy. It is already known that SpyGlass is beneficial in patients with difficult bile duct stones and indeterminate biliary lesions through the use of targeted lithotripsy and visually guided biopsy. Cholangioscopy allows the visualization of hidden stone and guide wire placement across difficult strictures and selective cannulation of the intrahepatic and cystic ducts. It is also demonstrating its utility in investigational applications such as post-liver transplant and primary sclerosing cholangitis stricture treatment, evaluation of hemobilia, and guided radiofrequency ablation of ductal tumors. In addition to having clinical utility, cholangioscopy may also be cost-effective by limiting the number of repeat procedures. Cholangioscopy overall has similar complication rates compared to other standard endoscopic retrograde cholangioscopy (ERCP) techniques, but there may be higher rates of cholangitis. This could be mitigated with prophylactic antibiotic use, and overall, cholangioscopy has similar complication rates compared to other techniques.

Optimizing Outcomes of Single-Operator Cholangioscopy-Guided Biopsies Based on a Randomized Trial

BACKGROUND & AIMS

Although single-operator cholangioscopy is considered to be the most sensitive method for tissue acquisition in patients with indeterminate bile duct strictures (IBDS), methods are needed to optimize the specimen collection and processing techniques. We aimed to determine the optimal method for specimen processing and identify the number of biopsies required to establish a definitive diagnosis.

METHODS

Patients with IBDS were randomly assigned to groups that underwent specimen processing using the onsite (n = 32) or offsite (n = 30) method. The primary outcome was to compare operating characteristics of onsite vs offsite specimen processing techniques. The secondary outcome was number of biopsies needed to establish definitive diagnosis. A final diagnosis was established at surgery or after a minimum clinical follow-up period of 18 months RESULTS: The final diagnosis was benign disease in 33 patients and malignancy in 29 patients. There were no significant differences between the offsite and onsite groups in diagnostic accuracy (90% vs 87.5%; P=.99), sensitivity (76.9% vs 75%; P=.99), specificity (100% vs 100%; P=.99), positive predictive value (100% vs 100%; P=.99), or negative predictive value (85% vs 80%; P=.99). Although diagnoses were established by analysis of a median of 1 biopsy in the onsite cohort (interquartile range, 1-1.5), the diagnostic accuracy was identical (90%) in each group, regardless of whether 3 or 4 biopsies were collected from each patient in the offsite cohort.

CONCLUSIONS

In a prospective comparative study, we found that centers without onsite cytopathology support that analyze 3 single-operator cholangioscopy-guided biopsies of a biliary stricture and process the specimens offsite make the correct diagnosis for 90% of cases. ClinicalTrials.gov, Number: NCT01815619.

Five Hub Genes Can Be The Potential DNA Methylation Biomarkers For Cholangiocarcinoma Using Bioinformatics Analysis

Background

Cholangiocarcinoma (CCA) is a subtype of highly malignant hepatic tumor, which has low 5-year survival rate and poor clinical outcome. Only a few patients can be detected early and accepted with the surgery. Most of CCA patients are diagnosed in advanced stage, and the treatments are limited. As for the inoperable, advanced CCA patients, chemotherapy is the main treatment, due to lacking molecular targets, therapeutic effect is limited.

Materials and methods

To explore potential therapeutic targets for CCA, we analyzed three microarray datasets derived from the Gene Expression Omnibus (GEO) database. Then, we used GEO2R tools of NCBI to discover the differentially expressed genes (DEGs) from the CCA and normal liver tumor microarrays (TMA). Subsequently, we used the Database for Annotation, Visualization and Integrated Discovery (DAVID GO) to perform the Gene Ontology function (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Then, we carried out the Cytoscape software to search for the hub genes downregulated in CCA and identify the protein–protein interaction (PPI) of these genes. Besides, we used the GEPIA tool to evaluate the differential expressions of hub genes in CCA patients. Then, we also used MEXPRESS database to detect the promoter methylation levels of hub genes in CCA and normal tissue samples. In addition, we evaluated the expression of these genes in CCA lines and normal bile tract cells after 5-AZA (DNA methyltransferase inhibitor) treatment.

Results

A total of 115 downregulated DEGs were identified. Among them, 10 hub genes with a high degree of connectivity were picked out. Among these 10 hub genes, F2, AHSG, ALDH8A1, SERPIND1 and AGXT showed higher DNA methylation levels of promoter in CCA compared with normal liver tissues. Therefore, these 5 genes may be the potential DNA methylation biomarkers and therapeutic targets in CCA.

Role of Ancillary Techniques in Biliary Cytopathology Specimens

Biliary brushing cytology has become the standard of practice for the investigation of strictures of the biliary and pancreatic duct systems. The methodology however has a limitation in that it has low diagnostic sensitivity when only cytologic evaluation is used. A number of testing methodologies have been applied to brushing specimens in an attempt to improve overall sensitivity without loss of specificity. These have included DNA ploidy analysis, immunocytochemistry, individual gene mutational analysis, fluorescence in-situ hybridization (FISH), and next generation sequencing (NGS). Currently, FISH coupled with routine cytology appears to be the method of choice for improving diagnostic sensitivity. NGS shows significant promise for improvement of diagnostic sensitivity.

Safety and efficacy of SpyGlass cholangiopancreatoscopy in routine clinical practice in a regional Singapore hospital

INTRODUCTION

This study examined the efficacy and safety of cholangiopancreatoscopy via the SpyGlass™ system in routine clinical practice.

METHODS

The clinical data of endoscopic retrograde cholangiopancreatography (ERCP) performed in a regional hospital from January 2013 to November 2016 was retrieved from an electronic database and reviewed. All patients who had undergone SpyGlass cholangiopancreatoscopy were enrolled. Patient demographics, procedure indication, technical success rates, clinical success rates and complication rates were analysed. A subanalysis of clinical outcomes was performed comparing the SpyGlass legacy (fibreoptic) and digital systems.

RESULTS

Out of 2,050 ERCP procedures performed, 47 patients underwent 50 cholangiopancreatoscopy procedures. Clinical indications were difficult common bile duct (CBD) stones (59.6%, n = 28), indeterminate CBD stricture (36.2%, n = 17), indeterminate pancreatic duct stricture (2.1%, n = 1) and proximally migrated CBD stent (2.1%, n = 1). Complete stone extraction was achieved in 26 (92.9%) out of 28 patients. Among patients with strictures, a correct diagnosis of malignancy based on image visualisation was achieved in all 11 cases. The sensitivity and specificity for SpyBite™ biopsies were 81.8% (95% confidence interval [CI] 48.2%-97.7%) and 100.0% (95% CI 15.8%-100.0%), respectively. The proximally migrated CBD stent was successfully extracted. Complications included pancreatitis (2.1%, n = 1), suspected sealed perforation after laser lithotripsy treated conservatively (2.1%, n = 1) and cholangitis (10.6%, n = 5). There was no difference in clinical outcomes between the SpyGlass legacy (n = 20) and digital (n = 30) systems.

CONCLUSION

SpyGlass cholangiopancreatoscopy is a safe and effective tool in routine clinical practice.

Review article: Asia-Pacific consensus recommendations on endoscopic tissue acquisition for biliary strictures

BACKGROUND

Pre-operative tissue diagnosis for suspected malignant biliary strictures remains challenging.

AIM

To develop evidence-based consensus statements on endoscopic tissue acquisition for biliary strictures.

METHODS

The initial draft of statements was prepared following a systematic literature review. A committee of 20 experts from Asia-Pacific region then reviewed, discussed, and modified the statements. Two rounds of independent voting were conducted to reach a final version. Consensus was considered to be achieved when 80% or more of voting members voted "agree completely" or "agree with some reservation."

RESULTS

Eleven statements achieved consensus. The choice of tissue sampling modalities for biliary strictures depends on the clinical setting, the location of lesion, and availability of expertise. Detailed radiological and endoscopic evaluation is useful to guide the selection of appropriate tissue acquisition technique. Standard intraductal biliary brushing and/or forceps biopsy is the first option when endoscopic biliary drainage is required with an overall (range) sensitivity and specificity of 45% (26%-72%) and 99% (98%-100%), and 48% (15%-100%) and 99% (97%-100%), respectively, in diagnosing malignant biliary strictures. Probe-based confocal laser endomicroscopy and fluorescence in situ hybridisation using 4 fluorescent-labelled probes targeting chromosomes 3, 7, 17 and 9p21 locus may be added to improve the diagnostic yield. Cholangioscopy-guided biopsy and EUS-guided tissue acquisition can be considered after prior negative conventional tissue sampling with an overall (range) sensitivity and specificity of 60% (38%-88%) and 98% (83%-100%), and 80% (46%-100%) and 97% (92%-100%), respectively, in diagnosing malignant biliary strictures.

CONCLUSION

These consensus statements provide evidence-based recommendations for endoscopic tissue acquisition of biliary strictures.

Emerging Technologies for the Diagnosis of Perihilar Cholangiocarcinoma

The diagnosis of malignant biliary strictures remains problematic, especially in the perihilar region and in primary sclerosing cholangitis (PSC). Conventional cytology obtained during endoscopic retrograde cholangiography (ERC)-guided brushings of biliary strictures is suboptimal due to limited sensitivity, albeit it remains the gold standard with a high specificity. Emerging technologies are being developed and validated to address this pressing unmet patient need. Such technologies include enhanced visualization of the biliary tree by cholangioscopy, intraductal ultrasound, and confocal laser endomicroscopy. Conventional cytology can be aided by employing complementary and advanced cytologic techniques such as fluorescent in situ hybridization (FISH), and this technique should be widely adapted. Interrogation of bile and serum by examining extracellular vesicle number and cargo, and exploiting next-generation sequencing and proteomic technologies, is also being explored. Examination of circulating cell-free deoxyribonucleic acid (cfDNA) for differentially methylated regions is a promising test which is being rigorously validated. The special expertise required for these analyses has to date hampered their validation and adaptation. Herein, we will review these emerging technologies to inform the reader of the progress made and encourage further studies, as well as adaptation of validated approaches.

How SpyGlass™ May Impact Endoscopic Retrograde Cholangiopancreatography Practice and Patient Management

INTRODUCTION

Cholangiopancreatoscopy with SpyGlass™ Direct Visualization System (SGDVS) is being used in specialized centers for improving the sensitivity of endoscopic retrograde cholangiopancreatography (ERCP) in patients with indeterminate pancreatobiliary strictures (PBS). The aims of this study were to report our initial experience with SGDVS in the evaluation of indeterminate PBS, and discuss the improvements of ERCP brought by this technique in our center.

METHODS

The usefulness of SGDVS in patients with indeterminate PBS (defined after nondiagnostic previous ERCP with brush cytology) was evaluated in a prospective observational cohort study conducted at a single tertiary biliopancreatic unit. The accuracy of diagnosis by the SGDVS visual findings, SGDVS-guided biopsy, technical success, image quality, change in patient management after the procedure, and complication rate were assessed.

RESULTS

In our single-center cohort, there were 13 SGDVS procedures for evaluating indeterminate PBS. Technical success, defined by the ability to progress with the SpyScope to the target lesion, was achieved in all the cases. The diagnostic accuracy of visual findings (87.5%) was superior to SGDVS-guided biopsy (55%). In 11 (85%) procedures, the image quality was considered good. The procedure permitted exclusion of malignancy and avoiding surgery in 9 patients (69%). There were no complications during the procedures. However, in the post-procedure monitoring, 3 patients developed acute pancreatitis (19%) and 2 patients developed acute cholangitis (13%).

CONCLUSION

The SGDVS can be considered useful in the context of indeterminate PBS. The intervention is associated with high procedural success and alters clinical outcome compared to conventional approaches.