Forceps biopsy and brush cytology during endoscopic retrograde cholangiopancreatography for the diagnosis of biliary stenoses

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.

Fluorescence In Situ Hybridization in Primary Diagnosis of Biliary Strictures: A Single-Center Prospective Interventional Study

Background and aims: Diagnosis of the biliary stricture remains a challenge. In view of the low sensitivity of brush cytology (BC), fluorescence in situ hybridization (FISH) has been reported as a useful adjunctive test in patients with biliary strictures. We aimed to determine performance characteristics of BC and FISH individually and in combination (BC + FISH) in the primary diagnosis of biliary strictures. Methods: This single-center prospective study was conducted between April 2019 and January 2021. Consecutive patients with unsampled biliary strictures undergoing first endoscopic retrograde cholangiopancreatography in our institution were included. Tissue specimens from two standardized transpapillary brushings from the strictures were examined by routine cytology and FISH. Histopathological confirmation after surgery or 12-month follow-up was regarded as the reference standard for final diagnosis. Results: Of 109 enrolled patients, six were excluded and one lost from the final analysis. In the remaining 102 patients (60.8% males, mean age 67.4, range 25–92 years), the proportions of benign and malignant strictures were 28 (27.5%) and 74 (72.5%), respectively. The proportions of proximal and distal strictures were 26 (25.5%) and 76 (74.5%), respectively. In comparison to BC alone, FISH increased the sensitivity from 36.1% to 50.7% (p = 0.076) while maintaining similar specificity (p = 0.311). Conclusions: Dual-modality tissue evaluation using BC + FISH showed an improving trend in sensitivity for the primary diagnosis of biliary strictures when compared with BC alone.

Bile duct dysplasia and associated invasive carcinoma: clinicopathological features, diagnosis, and practical challenges

Cholangiocarcinoma represents the second most frequent type of primary liver cancer that develops through a multistep histopathologic sequence. Dysplasia in the biliary tract epithelium is a precursor lesion of cholangiocarcinoma. This review provides a practical overview of bile duct dysplasia in relation to invasive carcinoma, covering clinicopathological features, diagnostic criteria, differential diagnosis, useful testing modalities, and challenges in daily practice. The key features of biliary intraepithelial neoplasia, intraductal papillary neoplasm, intraductal tubulopapillary neoplasm, and mucinous cystic neoplasm are described. Important differential diagnoses are included. Common pitfalls in histopathologic interpretation of bile duct biopsies and frozen sections are discussed.

Observation for the feasibility of a bile duct biopsy technique using a loop-tip guidewire during endoscopic retrograde cholangiopancreatography

Endoscopists frequently have difficulty approaching biliary lesions using biopsy forceps. The aim of this study was not only to describe an easy technique for biliary biopsy assisted by a looped guidewire but also to present preliminary results regarding its safety and feasibility. A preliminary proof-of-concept study was performed at a single tertiary medical center. Between August 2019 and January 2020, 13 patients with bile duct strictures underwent endoscopic retrograde cholangiopancreatography (ERCP) with a new loop guidewire-assisted forceps approach technique. The efficacy and safety were evaluated using the success rate as the primary outcome and diagnostic yield and complication rates as secondary outcomes. The tissue sampling success rate was 100% (13/13). All samples were acceptable for histopathological analysis. Eleven specimens were confirmed to be adenocarcinomas. After reexamination of the remaining 2 patients, all cases were eventually diagnosed as being malignant. The sensitivity of the single procedure was 84.6% (11/13). There were 2 patients with mild hyperamylasemia, but there were no severe complications with respect to safety. This new technique could enhance the success rate and diagnostic yield and reduce the risk of failure when using the biopsy forceps approach during ERCP.

Brush Cytology, Forceps Biopsy, or Endoscopic Ultrasound-Guided Sampling for Diagnosis of Bile Duct Cancer: A Meta-Analysis

Endoscopic sampling is essential for tissue diagnosis of cholangiocarcinoma (CCA). To evaluate and compare the diagnostic sensitivities of endoscopic retrograde cholangiopancreatography-guided brush cytology biopsy, and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in patients with CCA. A comprehensive literature search through multiple databases was conducted for articles published between January 1995 and August 2020. The pooled rates of sensitivity for the diagnosis of CCA and of adverse events were compared among brushing, biopsy, brushing & biopsy, and EUS-FNA. In total, 1123 patients with CCA (32 studies), 719 patients (20 studies), 358 patients (13 studies), and 422 patients (17 studies) were tested by brushing, biopsy, brushing & biopsy, and EUS-FNA, respectively. The pooled diagnostic sensitivity was 56.0% (95% confidence interval (CI) 48.8-63.1%, I² = 83.0%) with brushing, 67.0% (95% CI 60.2-73.5%, I² = 72.5%) with biopsy, 70.7% (95% CI 64.1-76.8%, I² = 42.7%) with brushing & biopsy, and 73.6% (95% CI 64.7-81.5%, I² = 74.7%) with EUS-FNA. The diagnostic sensitivity was significantly lower for brushing than for biopsy, brushing & biopsy, or EUS-FNA. No significant difference was noted in diagnostic sensitivities among biopsy, brushing & biopsy, and EUS-FNA. Adverse events were comparable between the groups. Intraductal biopsy, brushing & biopsy, and EUS-FNA had comparable efficacy and safety for the diagnosis of CCA. Brushing was the least sensitive diagnostic tool compared with intraductal biopsy or EUS-FNA. Given the modest diagnostic sensitivities of intraductal biopsy and EUS-FNA in the diagnosis of CCA, further studies for complementing these techniques with biomarkers may be needed.

Endobiliary biopsy

The differential diagnosis between benign and malignant biliary strictures is challenging and requires a multidisciplinary approach with the use of serum biomarkers, imaging techniques, and several modalities of endoscopic or percutaneous tissue sampling. The diagnosis of biliary strictures consists of laboratory markers, and invasive and non-invasive imaging examinations such as computed tomography (CT), contrast-enhanced magnetic resonance cholangiopancreatography, and endoscopic ultrasonography (EUS). Nevertheless, invasive imaging modalities combined with tissue sampling are usually required to confirm the diagnosis of suspected malignant biliary strictures, while pathological diagnosis is mandatory to decide the optimal therapeutic strategy. Although EUS-guided fine-needle aspiration biopsy is currently the standard procedure for tissue sampling of solid pancreatic mass lesions, its diagnostic value in intraductal infiltrating type of cholangiocarcinoma remains limited. Moreover, the "endobiliary approach" using novel slim biopsy forceps, transpapillary and percutaneous cholangioscopy, and intraductal ultrasound-guided biopsy, is gaining ground on traditional endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography endobiliary forceps biopsy. This review focuses on the available endobiliary techniques currently used to perform biliary strictures biopsy, comparing the diagnostic performance of endoscopic and percutaneous approaches.

Role of DNA Flow Cytometry in the Diagnosis of Malignancy in Bile Duct Biopsies Using Paraffin-Embedded Tissue

OBJECTIVES

Histopathologic evaluation of bile biopsies for biliary strictures is frequently challenging and is affected by interobserver disagreement. Reliable ancillary tests that can help differentiate benign from malignant are not available. This study aimed to evaluate whether DNA content abnormalities detected by flow cytometry on formalin-fixed, paraffin-embedded (FFPE) tissue can help differentiate benign/reactive, dysplastic from malignant cell populations in bile duct biopsies.

METHODS

We performed DNA flow cytometry on 30 FFPE bile duct biopsies in 5 well-defined diagnostic categories: (1) negative for dysplasia (NED), (2) low-grade dysplasia (LGD), (3) high-grade dysplasia (HGD), (4) carcinoma (CA), and (5) indefinite for dysplasia (IND).

RESULTS

Abnormal DNA content was detected in 0 NED, 5 LGD (62.5%), 2 HGD (33.3%), 3 CA (60%), and 4 IND (80%) samples. As a diagnostic marker, the estimated sensitivity, specificity, positive predictive value, and negative predictive value were 63%, 100%, 100%, and 50%, respectively, for diagnosing HGD or CA.

CONCLUSIONS

DNA flow cytometry analysis is a useful ancillary test for the interpretation of bile duct biopsies. DNA content abnormalities, when correlated with histologic findings, will not only help confirm the morphologic impression but also identify patients who are at a higher risk of developing malignancy.

Biliary Tree Diagnostics: Advances in Endoscopic Imaging and Tissue Sampling

The diagnostic approach to the biliary tree disorders can be challenging, especially for biliary strictures. Albeit the great diagnostic impact of endoscopic retrograde cholangiopancreatography (ERCP) which allows one to obtain fluoroscopic imaging and tissue sampling through brush cytology and/or forceps biopsy, a considerable proportion of cases remain indeterminate, leading to the risk of under/over treated patients. In the last two decades, several endoscopic techniques have been introduced in clinical practice, shrinking cases of uncertainties and improving diagnostic accuracy. The aim of this review is to discuss recent advances and emerging technologies applied to the management of biliary tree disorders through peroral endoscopy procedures.

Dysbiosis of the duodenal microbiota as a diagnostic marker for pancreaticobiliary cancer

BACKGROUND

Pancreaticobiliary cancer (PB Ca) is a lethal disease, and a useful diagnostic marker is urgently needed. A correlation between the human microbiota and malignant gastrointestinal diseases was recently reported.

AIM

To investigate the efficacy of the duodenal microbiota for diagnosing PB Ca.

METHODS

We recruited 22 patients with benign pancreaticobiliary diseases (benign group) and 12 patients with PB Ca (malignant group). The duodenal microbiota of each patient was analyzed by the 16S rDNA terminal restriction fragment length polymorphism method. Patient characteristics, tumor markers, and relative abundances of the duodenal microbiota were compared between the benign and malignant groups.

RESULTS

Cancer antigen 19-9 (CA19-9), Bifidobacterium, Clostridium cluster XVIII, and Prevotella levels differed significantly between the benign and malignant groups. Clostridium cluster XVIII had the greatest area under the receiver operating characteristic curve (AUC) among the four factors with respect to diagnosing PB Ca (cutoff value: 3.038%; sensitivity: 58.3%; specificity: 95.2%; AUC: 0.81). The combination of Clostridium cluster XVIII (cutoff value: 3.038%) and CA19-9 Levels (cutoff value: 18.8 U/mL) showed 91.7% sensitivity and 71.4% specificity for diagnosing PB Ca.

CONCLUSION

The duodenal microbiota may be useful for PB Ca screening.

Tissue Sampling through Endoscopic Ultrasound-Guided Fine Needle Aspiration versus Endoscopic Retrograde Cholangiopancreatographic Brushing Cytology Technique in Suspicious Malignant Biliary Stricture

BACKGROUND Differentiation of benign and malignant biliary strictures plays a pivotal role in managing biliary strictures. Brush cytology via endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) are two diagnostic methods. In the present study, we aimed to compare the accuracy of the results of EUS-FNA and ERCP-based sampling of biliary strictures. METHODS In a prospective study, between January 2019 and March 2020, patients with indeterminate biliary strictures who had no history of hepatobiliary surgery, opium usage, cancer of pancratobiliary system, and acute liver disease were selected. They underwent EUS and ERCP in the same session. They were followed up for 6 months, and the sensitivity, specificity, positive and negative predictive values, and accuracy of these imaging modalities were compared. RESULTS A total of 60 patients were enrolled. 28 lesions were located in the distal and 32 lesions in the proximal parts of the biliary tree. 55 malignant and 5 benign lesions were diagnosed. The sensitivity and accuracy of EUS-FNA and ERCP tissue sampling were 78.2% and 80.0% versus 50.9% and 55.0%, respectively (p = 0.024). The combination of both methods improved the sensitivity and accuracy to 85.5% and 86.7%, respectively. Regarding the location, EUS-FNA is superior to ERCP-brush cytology in diagnosing proximal lesions with sensitivity and specificity of 73.3% and 75.0% vs. 50.0% and 53.1%, respectively (p = 0.04). CONCLUSION EUS-FNA is superior to ERCP brushing in the diagnosis of indeterminate biliary strictures, particularly in distal lesions. Combining ERCP brushing and EUS-FNA improves the diagnosis accuracy.

Fluoroscopy-guided shaped endobiliary biopsy at endoscopic retrograde cholangiography can accurately diagnose biliary neoplasia: Results from a large cohort

Background and study aims  The sensitivity of using standard endobiliary forceps biopsy to diagnose neoplastic biliary lesions remains low. We have developed a unique biopsy approach, termed fluoroscopy-guided, shaped endobiliary biopsy (FSEB), in which the biopsy forceps are modified to improve diagnostic yield. In this study, we evaluate the diagnostic characteristics of FSEB for endobiliary lesions at endoscopic retrograde cholangiography (ERC). Patients and methods  Consecutive patients undergoing FSEB between 1/2001 and 12/2014 were retrospectively enrolled. The identification of neoplastic lesions with FSEB, was the primary endpoint. The gold standard of neoplasia was histopathology, cytology or surgical histopathology. The benign cases were followed up for one year. Results  A total of 204 patients undergoing 250 biopsy sessions by FSEB were analyzed. Per-patient analysis was performed and FSEB showed 81.1 % sensitivity and 88.2 % accuracy. FSEB detection of proximal biliary lesions was more sensitive (91.1 % vs 73.2 %, P  < 0.01) and accurate (94.9 % vs 82.2 %, P  < 0.01) compared to distal lesions. No complications from FSEB were reported. Conclusions  FSEB shows high accuracy for diagnosis of neoplasia in biliary strictures, especially for proximal lesions. Future prospective randomized controlled studies are merited to further validate the role of FSEB as the first-line sampling tool for evaluation of biliary neoplasm.

Optimal tissue sampling during ERCP and emerging molecular techniques for the differentiation of benign and malignant biliary strictures

Patients with cholangiocarcinoma have poor survival since the majority of patients are diagnosed at a stage precluding surgical resection, due to locally irresectable tumors and/or metastases. Optimization of diagnostic strategies, with a principal role for tissue diagnosis, is essential to detect cancers at an earlier stage amenable to curative treatment. Current barriers for a tissue diagnosis include both insufficient tissue sampling and a difficult cyto- or histopathological assessment. During endoscopic retrograde cholangiopancreatography, optimal brush sampling includes obtaining more than one brush within an individual patient to increase its diagnostic value. Currently, no significant increase of the diagnostic accuracy for the new cytology brush devices aiming to enhance the cellularity of brushings versus standard biliary brush devices has been demonstrated. Peroral cholangioscopy with bile duct biopsies appears to be a valuable tool in the diagnostic work-up of indeterminate biliary strictures, and may overcome current technical difficulties of fluoroscopic-guided biopsies. Over the past years, molecular techniques to detect chromosomal instability, mutations and methylation profiling of tumors have revolutionized, and implementation of these techniques on biliary tissue during diagnostic work-up of biliary strictures may be awaited in the near future. Fluorescence in situ hybridization has already been implemented in routine diagnostic evaluation of biliary strictures in several centers. Next-generation sequencing is promising for standard diagnostic care in biliary strictures, and recent studies have shown adequate detection of prevalent genomic alterations in KRAS, TP53, CDKN2A, SMAD4, PIK3CA, and GNAS on biliary brush material. Detection of DNA methylation of tumor suppressor genes and microRNAs may evolve over the coming years to a valuable diagnostic tool for cholangiocarcinoma. This review summarizes optimal strategies for biliary tissue sampling during endoscopic retrograde cholangiopancreatography and focuses on the evolving molecular techniques on biliary tissue to improve the differentiation of benign and malignant biliary strictures.

Combination of ERCP-Based Modalities Increases Diagnostic Yield for Biliary Strictures

BACKGROUND

Biliary stricture evaluation with brush cytology and intraductal forceps biopsy carries a low sensitivity, but the combination of newer modalities may improve sensitivity.

AIM

To determine whether the addition of advanced modalities increases diagnostic yield of ERCP-based sampling.

METHODS

This single-center retrospective study evaluates patients with biliary strictures sampled using brush cytology. Operating characteristics were calculated for individual and combinations of modalities including cholangioscopy, fluoroscopy- and cholangioscopy-directed intraductal biopsy, fluorescence in situ hybridization (FISH), and confocal laser endomicroscopy. Analyses under Standard Criteria (SC) included malignant results as "positive" and Expanded Criteria (EC) included "suspicious" and "high-grade dysplasia" results as "positive."

RESULTS

A total of 614 patients were included, and 354 (57.8%) received brush cytology alone, which had a sensitivity of 38.5% (SC) to 40.3% (EC) and a specificity of 97.8% (EC) to 99.3% (SC). Combining brush cytology with fluoroscopy-guided biopsy (n = 259, 42.2%) had a sensitivity of 62.5% (SC) to 67.9% (EC) and specificity of 90.2% (EC) to 96.7% (SC). Adding FISH to brush cytology had a sensitivity of 84.2% (SC) to 87.5% (EC) and specificity of 54.1% (SC and EC), while cholangioscopy visualization addition resulted in a sensitivity of 80.4% (SC) to 92.2% (EC) and specificity of 67.3% (EC) to 89.1% (SC). There were no significant differences in sensitivity and specificity using SC and EC.

CONCLUSIONS

Brush cytology has a low sensitivity, but the addition of other modalities increases sensitivity. There was no difference in specificity between the SC and the EC, supporting the inclusion of "suspicious" impressions with malignant results at our center.

High-Resolution Probe-Based Confocal Laser Endomicroscopy for Diagnosing Biliary Diseases

Probe-based confocal laser endomicroscopy is an endoscopic technique that enables in vivo histological evaluation using fluorescent pigment. The ability to diagnostically differentiate between benign and malignant biliary disease using the "CholangioFlexTM", a dedicated biliary device, has been reported. However, the Miami and Paris classifications, used as diagnostic criteria, mainly evaluate findings in the submucosa, and visualizing the epithelium as the main site of lesions remains difficult. To address this problem, we verified the imaging findings and diagnostic ability of three types of probes: CholangioFlexTM, GastroFlexTM, and AlveoFlexTM. With GastroFlexTM, the clear mucosal epithelium was observed, and differential diagnoses as benign/malignant could be made based on epithelial findings. GastroFlexTM may be a good first-choice probe for probe-based confocal laser endomicroscopy of biliary diseases, and a new diagnostic classification based on bile duct epithelial findings may provide useful criteria independent of the Miami or Paris classifications.

Diagnostic Process Using Endoscopy for Biliary Strictures: A Narrative Review

The diagnostic process for biliary strictures remains challenging in some cases. A broad differential diagnosis exists for indeterminate biliary strictures, including benign or malignant lesions. The diagnosis of indeterminate biliary strictures requires a combination of physical examination, laboratory testing, imaging modalities, and endoscopic procedures. Despite the progress of less invasive imaging modalities such as transabdominal ultrasonography, computed tomography, and magnetic resonance imaging, endoscopy plays an essential role in the accurate diagnosis, including the histological diagnosis. Imaging findings and brush cytology and/or forceps biopsy under fluoroscopic guidance with endoscopic retrograde cholangiopancreatography (ERCP) are widely used as the gold standard for the diagnosis of biliary strictures. However, ERCP cannot provide an intraluminal view of the biliary lesion, and its outcomes are not satisfactory. Recently, peroral cholangioscopy, confocal laser endomicroscopy, endoscopic ultrasound (EUS), and EUS-guided fine-needle aspiration have been reported as useful for indeterminate biliary strictures. Appropriate endoscopic modalities need to be selected according to the patient's condition, the lesion, and the expertise of the endoscopist. The aim of this review article is to discuss the diagnostic process for indeterminate biliary strictures using endoscopy.

Comparison of the Diagnostic Performance of Novel Slim Biopsy Forceps with Conventional Biopsy Forceps for Biliary Stricture: A Multicenter Retrospective Study

Novel slim biopsy forceps provide some technical advantages to facilitate a more accurate diagnosis, although we are not aware of any comparative studies. Therefore, we compared tissue acquisition and diagnostic accuracy between novel slim biopsy forceps and conventional biopsy forceps in cases with a biliary stricture. We reviewed 341 patients who underwent endoscopic retrograde cholangiopancreatography for the histological confirmation of biliary stricture at two tertiary hospitals between 2013 and 2020. The primary endpoint was the forceps’ diagnostic accuracies. We included 276 patients who underwent biopsy using the novel forceps (n = 130) or conventional forceps (n = 146). The novel forceps provided 81.7% sensitivity, 100.0% specificity, positive-predictive value (PPV) of 100.0%, and negative-predictive value (NPV) of 57.8%, with an accuracy of 85.4% when the diagnosis by endobiliary biopsy included suspected or positive malignancy. The conventional forceps provided 61.7% sensitivity, 100.0% specificity, PPV of 100.0%, and NPV of 36.1%, with an accuracy of 68.5%. Only novel forceps use was significantly associated with an accurate diagnosis (odds ratio: 2.70, 95% confidence interval: 1.52–5.00). There were no significant inter-group differences in the procedure-related rates of adverse events. Endobiliary biopsy using novel forceps offered better diagnostic performance and more acceptable procedure-related adverse events than conventional forceps.

Probe-based confocal laser endomicroscopy for the diagnosis of pancreatic ductal structures

BACKGROUND AND AIM

The image-based diagnosis of pancreatic diseases can be difficult and requires pathological evaluation. Probe-based confocal laser endomicroscopy (pCLE) enables real-time observation of the microscopic tissue pattern of lesion and may be a useful assistance for the diagnosis. This study aimed to evaluate the feasibility and utility of pCLE for the diagnosis of pancreatic diseases.

METHODS

Thirty patients who underwent endoscopic retrograde cholangiopancreatography with pCLE for the evaluation of indeterminate pancreatic diseases from June 2015 to October 2018 were included in this study. The pCLE findings were interpreted according to the Miami Classification.

RESULTS

Among a total of 30 patients, 12, 10, 4, and 4 patients received the definitive diagnoses of pancreatic ductal adenocarcinoma (PDAC), main duct intrapapillary mucinous neoplasm, autoimmune pancreatitis, and chronic pancreatitis, respectively. The diagnostic accuracy of pCLE for PDAC and pancreatitis (96.7% and 93.3%, respectively) was higher than that of cytology (76.7% and 63.3%, respectively) (P = 0.0227 and 0.0048, respectively). The sensitivity of pCLE for PDAC was significantly higher (91.7%) than that of cytology (41.7%) (P = 0.0094). Moreover, the specificity of pCLE for pancreatitis was significantly higher than that of cytology (90.9% vs 50%; P = 0.0029). However, the diagnostic accuracies of pCLE and cytology for main duct intrapapillary mucinous neoplasm did not differ significantly (96.7% and 86.7%, respectively).

CONCLUSIONS

Probe-based confocal laser endomicroscopy may be effective for the diagnosis of pancreatic diseases as adjunct modality. It requires technical learning and further evaluation of its usefulness.

Interobserver agreement in pathologic evaluation of bile duct biopsies

Intraductal biopsy is commonly used for preoperative evaluation of the etiology of biliary strictures. Interpretation of intraductal biopsies is frequently challenging. The diagnosis often suffers from interobserver disagreement, which has not been studied in the literature. We sought to assess interobserver concordance in the interpretation of intraductal biopsies. Eighty-five biopsies were retrieved, falling into five diagnostic categories: negative for dysplasia (NED), indefinite for dysplasia (IND), low-grade dysplasia (LGD), high-grade dysplasia (HGD), and carcinoma (CA). Eight gastrointestinal pathologists blindly reviewed all the slides. Agreement among pathologists was analyzed using Fleiss κ and weighted concordance coefficient S∗. A face-to-face consensus/training session was held to discuss the classification criteria, followed by a second round review. The overall interobserver agreement was fair in the first round review (κ = 0.39; S∗ = 0.56) and improved to moderate in the second round review (κ = 0.48; S∗ = 0.69). The agreement before and after consensus meeting was substantial to nearly perfect for CA (κ = 0.65, S∗ = 0.83; and κ = 0.80, S∗ = 0.91), fair for HGD (κ = 0.28, S∗ = 0.69; and κ = 0.40, S∗ = 0.63), and moderate for NED (κ = 0.47, S∗ = 0.50; and κ = 0.47, S∗ = 0.53). Agreement improved from fair to moderate for LGD (κ = 0.36, S∗ = 0.61; and κ = 0.49, S∗ = 0.71) and slight to fair for IND (κ = 0.16, S∗ = 0.51; and κ = 0.33, S∗ = 0.50). Compared with Hollande's fixed specimens, the agreement was higher in almost all diagnostic categories in formalin-fixed biopsies. Overall, interobserver concordance was improved after a consensus/training session. Interobserver reproducibility was high at the end of the diagnostic spectrum (CA) but fair to moderate for other diagnostic categories.

Endoscopic retrograde cholangiopancreatography guided interventions in the management of pancreatic cancer

Pancreatic cancer is the leading cause of cancer-related morbidity and mortality with an overall five-year survival of less than 9% in the United States. At presentation, the majority of patients have painless jaundice, pruritis, and malaise, a triad that develops secondary to obstruction, which often occurs late in the course of the disease process. The technical advancements in radiological imaging and endoscopic interventions have played a crucial role in the diagnosis, staging, and management of patients with pancreatic cancer. Endoscopic retrograde cholangiopancreatography (ERCP)-guided diagnosis (with brush cytology, serial pancreatic juice aspiration cytologic examination technique, or biliary biopsy) and therapeutic interventions such as pancreatobiliary decompression, intraductal and relief of gastric outlet obstruction play a pivotal role in the management of advanced pancreatic cancer and are increasingly used due to improved morbidity and complication rates compared to surgical management. In this review, we highlight various ERCP-guided diagnostic and therapeutic interventions for the management of pancreatic cancer.

Comparison of the Diagnostic Performances of Same-session Endoscopic Ultrasound- and Endoscopic Retrograde Cholangiopancreatography-guided Tissue Sampling for Suspected Biliary Strictures at Different Primary Tumor Sites

Background/Aims

Determining the cause of suspected biliary stricture is often challenging in clinical practice. We aimed to compare the diagnostic yields of endoscopic ultrasound-guided tissue sampling (EUS-TS) and endoscopic retrograde cholangiopancreatography-guided tissue sampling (ERCP-TS) in patients with suspected biliary stricture at different primary lesions.

Methods

We enrolled patients who underwent same-session EUS- and ERCP-TS for the evaluation of suspected biliary stricture. Forceps biopsy and/or brush cytology of intraductal lesions and fine-needle aspiration for solid mass lesions were performed during ERCP and EUS, respectively.

Results

One hundred and twenty-five patients treated at our institution between January 2011 and September 2016, were initially considered for the study. However, 32 patients were excluded due to loss of follow-up (n=8) and ERCP-TS on the pancreatic duct (n=20) or periampullary lesions (n=4). Of the 93 patients included, 86 had a malignant tumor including cholangiocarcinoma (n=39), pancreatic cancer (n=37), and other malignancies (n=10). Seven patients had benign lesions. EUS-TS had higher rate of overall diagnostic accuracy than ERCP-TS (82.8% vs. 60.2%, p=0.001), and this was especially true for patients with a pancreatic lesion (84.4% vs. 51.1%, p=0.003).

Conclusions

EUS-TS was found to be superior to ERCP-TS for evaluating suspected biliary strictures, especially those caused by pancreatic lesions.

Impact of peroral cholangioscopy on the management of indeterminate biliary conditions: a multicentre prospective trial

BACKGROUND AND AIMS

Single-operator cholangioscopy (SOC) can help diagnose biliopancreatic conditions. The impact of SOC on patient outcome has never been specifically addressed.

PATIENTS AND METHODS

Consecutive patients bearing indeterminate biliary strictures (IDBS), or primary sclerosing cholangitis (PSC) with suspected cholangiocarcinoma, were included. Patients with IDBS had at least one previous inconclusive endoscopic retrograde cholangio pancreatography (ERCP) + cytology. Primary endpoint was the difference in adequacy of management planned before and after SOC with regard to final diagnosis obtained after surgery or 24 months follow-up.

DESIGN

Prospective open-label multicentre trial.

RESULTS

61 patients were included (IDBS: 48; PSC: 13); 70.5% had a benign lesion (IDBS 66.7%, PSC 84.6%). The management adequacy rate was significantly higher after SOC than before SOC overall (p<10^-5), in IDBS (p<0.001) and PSC (p<0.05) patients. SOC induced changes in the management of the majority of patients in all groups (60.3%). The overall sensitivity of combined visual impression and biopsy ranged from 52% to 63.6% depending on investigator or independent expert rating (κ 0.92-0.96), whereas specificity, positive and negative predictive values of SOC were, respectively, 100%, 100% and 83.6%. Patient management observed at the end of follow-up was consistent with that anticipated after SOC in 88.5% overall.

CONCLUSION

Despite a moderate sensitivity for the diagnosis of malignancy, SOC has a dramatic impact on the management of patients with IDBS and PSC with suspected carcinoma. Cholangioscopy might be implemented in the workup of selected patients with challenging diagnosis, when a significant impact on outcome (essentially resection vs conservative management) is to be expected.

Individual probe based confocal laser endomicroscopy criteria in the analysis of indeterminate biliary strictures

OBJECTIVES

Evaluation of indeterminate biliary strictures remains challenging due to limited sensitivity of endoscopic tissue sampling. Biliary probe-based confocal laser endomicroscopy (pCLE) has shown promise to detect and exclude neoplasia. However, knowledge of whether individual inflammatory criteria are more prevalent in neoplasia compared to benign strictures is limited. The objective of this work is to improve diagnosis of neoplastic and inflammatory conditions using pCLE.

MATERIALS AND METHODS

The charts of all patients who underwent pCLE at a single referral center between 2009 and 2015 were reviewed. ERCP reports were reviewed for eleven Miami and Paris criteria. Primary outcome was the identification of neoplasia by histopathology (defined as high-grade dysplasia and/or adenocarcinoma). To model predictors of neoplasia, we fit a binary regression model incorporating data from pCLE operating criteria, pCLE impression, and PSC status.

RESULTS

97 patients were identified. In the 27 patients with neoplasia, there was increasing number of Miami malignant criteria (Pearson r = 0.512, p < .001) while inflammatory criteria were less prevalent. 10% (5/51, p < .001) of patients with benign pCLE impression developed neoplasia, while 48% (22/46, p < .001) with suspicious pCLE impressions developed neoplasia. The binary regression model to predict neoplasia had a sensitivity of 83.3%, specificity of 92.5%, and overall accuracy 89.7%.

CONCLUSIONS

Presence of malignant criteria and absence of certain inflammatory criteria are more prevalent in patients with neoplasia. Our model, which weights individual imaging components, shows impressive sensitivity and specificity over prior prognostic efforts. Prospective studies will be required to evaluate this model.

Appropriate number of biliary biopsies and endoscopic retrograde cholangiopancreatography sessions for diagnosing biliary tract cancer

BACKGROUND

Biliary ductal cancer (BDC) is a lethal disease; however, diagnosing BDC is challenging. Biliary biopsies are performed to pathologically diagnose BDC, but the appropriate parameters for biliary biopsy [number of biliary biopsies, number of endoscopic retrograde cholangiopancreatography (ERCP) sessions, etc.] are unknown.

AIM

To clarify what constitutes an adequate method for biliary biopsy.

METHODS

In total, 95 patients who underwent endoscopic biliary biopsy without choledochoscopy and who were pathologically diagnosed with BDC were enrolled in this study. The patients were divided into two groups. Seventy-six patients who were diagnosed by biliary biopsy were defined as the positive group (P group), and nineteen patients who were not diagnosed by biliary biopsy were defined as the negative group (N group). The patient characteristics and ERCP-related procedures were compared between the P and N groups.

RESULTS

The numbers of ERCP sessions and biliary biopsies were significantly different between the two groups [ERCP sessions (one/two), P group 72/4 vs N group 15/4, P value = 0.048; number of biliary biopsies, P group 2 (1-6) vs N group 2 (1-7), P value = 0.039]. In a multivariate analysis, fewer than 2 ERCP sessions was an independent factor influencing the positivity of the biliary biopsies.

CONCLUSION

This study clarified that ERCP and biliary ductal biopsy should only be performed once. If biliary cancer is not pathologically diagnosed after the first ERCP session, other methods (Endoscopic ultrasonography-guided fine needle aspiration or choledochoscopy-guided biliary ductal biopsy) should be employed.

Diagnostic Ability of Endoscopic Bile Cytology Using a Newly Designed Biliary Scraper for Biliary Strictures

BACKGROUND

A new device with metallic wires for scrape cytology was developed.

AIMS

To compare the diagnostic performance of scrape cytology and conventional cytology during endoscopic retrograde cholangiopancreatography for biliary strictures.

METHODS

A total of 420 cases with biliary stricture underwent transpapillary bile cytology. Among them, there are 79 cases with scrape cytology using the new device (scrape group) and 341 cases with conventional cytology (control group). Seventy-two and 174 cases underwent biliary biopsy at the same time as bile cytology in the scrape and control group, respectively.

RESULTS

The sensitivity for malignancy of bile cytology in the scrape and control group was 41.2% [pancreatic cancer (PC): 23.1%, biliary cancer (BC): 52.5%] and 27.1% (PC: 16.3%, BC: 38.0%), respectively (P = 0.023). When analyzed PC and BC, respectively, there was no significant difference between the two groups. In the both groups, the sensitivity was significantly higher for BC than PC. In the scrape group, there was no difference in the sensitivity between cytology and biopsy [39.7% (PC: 17.4%, BC: 55.3%)], but in the control group, a significantly lower sensitivity was observed with cytology than biopsy (36.4% (PC: 19.7%, BC: 50.0%)) (P = 0.046). When analyzed PC and BC, respectively, there was no significant difference between cytology and biopsy. The sensitivity of combined cytology and biopsy was 55.6% (PC: 30.4%, BC: 71.1%) in the scrape group and 47.0% (PC: 24.6%, BC: 64.3%) in the control group.

CONCLUSION

Scrape bile cytology for biliary strictures may be superior to conventional cytology.

The efficacy of serum cell death biomarkers for diagnosing biliary tract cancer

In this study, we determined the efficacy of the cell death biomarker cytokeratin 18 for diagnosing biliary tract cancer (BTC). We recruited 36 patients with BTC (Malignant group) and 45 patients with benign biliary tract disease (Benign group) for this study. We used M30 and M65 as cell death biomarkers. M30 levels indicate apoptosis, and M65 levels indicate both apoptosis and necrosis. M30 and M65 levels were significantly higher in the Malignant group than in the Benign group (142.4 ± 117.0 vs 48.9 ± 71.2 U/l, P < 0.001; 1513.3 ± 837.4 vs 882.2 ± 831.2 U/l, P = 0.001). The diagnosability of M30 was the highest of the four markers (CEA, CA19-9, M30, M65) (cut-off value: 74.429 U/l, sensitivity: 72.2%, specificity: 77.1%, AUC: 0.771). The sensitivity of M30 (cut-off value: 74.429 U/l) was significantly higher than that of biliary cytology (76% (19/25) vs 12% (3/25), P < 0.001), and the accuracy of M30 was significantly higher than that of biliary cytology (78.3% (36/46) vs 52.2% (24/46), P = 0.015). The sensitivity of M30 (cut-off value: 74.429 U/l) was significantly higher than that of biliary cytology and brush cytology (72.4% (21/29) vs 24.1% (7/29), P < 0.001). In conclusion, cell death biomarkers were increased in patients with BTC, and M30 could efficiently diagnose BTC.

Novel triple lumen catheter for ERCP tissue diagnosis

INTRODUCTION

 The ideal endoscopic retrograde cholangiopancreatography (ERCP) tissue sampling technique should be simple, inexpensive, and yield sufficient tissue for histology while permitting contrast-guided targeting under fluorescence and multiple passes into the bile duct. Current techniques do not fulfill these requirements comprehensively. We designed a catheter for optimized targeting of large intrabiliary biopsies.

METHODS

 A 3.5-mm sterile, single-use prototype catheter was developed, with three independent lumina extending continuously to the distal tip for three distinct functions to be available simultaneously: passage of large volume biopsy forceps (1.8 mm), wire guidance (0.035″), and contrast injection.

RESULTS

 First clinical use in five patients (four transpapillary, one percutaneous access) allowed good intrabiliary manipulation in 4/5 patients. Contrast-guided sampling provided adequate specimens. No adverse events were noted.

DISCUSSION

 Technical aspects and preliminary clinical data for the novel triple lumen biopsy catheter are encouraging. The catheter allowed wire guidance and contrast application to guide sampling of larger pieces of tissue. In perspective, the working channel could host any accessory for targeted intrabiliary diagnosis and therapy, and catheter use is not limited to bile ducts.

Usefulness of Endoscopic Transpapillary Tissue Sampling for Malignant Biliary Strictures and Predictive Factors of Diagnostic Accuracy

BACKGROUND/AIMS

It is sometimes difficult to distinguish between malignant and benign biliary strictures using imaging studies alone, and pathological diagnosis is necessary. The aim of this study was to determine the usefulness of endoscopic transpapillary tissue sampling and factors predictive of diagnostic accuracy.

METHODS

From April 2008 to December 2014, 136 patients underwent endoscopic transpapillary tissue sampling for malignant biliary strictures. The cytological and histological findings were reported as negative, suspicious, or positive. Suspicious and positive findings were defined as pathologically positive.

RESULTS

The sensitivity was 65.0% for forceps biopsy, 49.5% for brush cytology, 46.2% for bile aspiration cytology, and 21.9% for endoscopic nasobiliary drainage cytology. The combination of these procedures improved the sensitivity (72.8%). Endoscopic transpapillary tissue sampling was more sensitive for lesions of biliary origin (91.4%) than for extrabiliary lesions (66.3%). In surgical cases, the sensitivity for tumors with an infiltrative growth pattern (53.3%) was significantly lower than for a tumor with an expanding or intermediate growth pattern (87.5%).

CONCLUSIONS

Combining procedures can improve diagnostic accuracy. It may be possible to predict the sensitivity of endoscopic transpapillary tissue sampling by evaluating the etiology and tumor growth pattern using preoperative imaging studies.

Diagnosis and Management of Intrahepatic and Extrahepatic Cholangiocarcinoma

Cholangiocarcinomas (CC) are rare tumors which usually present late and are often difficult to diagnose and treat. CCs are categorized as intrahepatic, hilar, or extrahepatic. Epidemiologic studies suggest that the incidence of intrahepatic CCs may be increasing worldwide. In this chapter, we review the risk factors, clinical presentation, and management of cholangiocarcinoma.

Brushing the distal biliary stricture in the surrounding of the papilla increased the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis: A retrospective study using propensity score analysis

Background and aims

Brushing cytology is useful for diagnosing biliary strictures. With regard to biliary stricture brushing at the distal common bile duct in the surrounding of the papilla, the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis is unknown. Our study aimed to evaluate the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis by using this procedure.

Methods

A total of 150 endoscopic retrograde cholangiopancreatography-naïve patients undergoing endoscopic retrograde cholangiopancreatography including biliary stricture brushing were retrospectively analyzed. Patients were divided into two groups: the surrounding of the papilla group (n = 25) and the other group (n = 125). The primary outcome was the post-endoscopic retrograde cholangiopancreatography pancreatitis incidence. We analyzed the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis by using inverse probability of treatment weighting based on propensity scores to adjust for selection bias.

Results

The overall incidence of post-endoscopic retrograde cholangiopancreatography pancreatitis was 11.3%, and post-endoscopic retrograde cholangiopancreatography pancreatitis of the surrounding of the papilla group occurred significantly more frequently than in the other group (32.0% vs 7.2%, p < 0.01). Multivariate analysis showed that this procedure was a risk factor for post-endoscopic retrograde cholangiopancreatography pancreatitis (odds ratio, 10.6; 95% confidence interval, 2.82-40.2; p < 0.01). In the propensity-weighted model, this procedure was an independent risk factor for post-endoscopic retrograde cholangiopancreatography pancreatitis (odds ratio, 8.42; 95% confidence interval, 2.12-32.4; p < 0.01) by multivariate analysis.

Conclusions

Biliary stricture brushing at the distal common bile duct in the surrounding of the papilla may increase the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis compared with brushing other portions.

Improved classification of indeterminate biliary strictures by probe-based confocal laser endomicroscopy using the Paris Criteria following biliary stenting

BACKGROUND AND AIMS

Probe-based confocal laser endomicroscopy (pCLE) using the Miami Criteria has improved classification of indeterminate biliary strictures. However, previous biliary stenting may result in their misclassification as malignant strictures. Inflammatory criteria were added to form the Paris Classification to prevent this misclassification and reduce false positives. The aim of this study was to assess if the Paris Classification was more accurate than the Miami Classification in classifying indeterminate biliary strictures after biliary stenting.

METHODS

This was a retrospective observational study involving 21 patients with indeterminate biliary strictures from whom 27 pCLE video sequences were obtained (20 benign and seven malignant). Patients with and without prior biliary stenting underwent pCLE. Two investigators classified the strictures as malignant or benign using the Miami and Paris Classifications. Diagnostic accuracy, sensitivity (Se), and specificity (Sp) of endoscopic retrograde-guided pCLE were compared with final histopathology.

RESULTS

In those without biliary stenting, the Miami Criteria resulted in Se 88%, Sp 75%, positive predictive value (PPV) 64%, negative predictive value (NPV) 92%, and accuracy 79%, while the Paris Classification resulted in Se 63%, Sp 88%, PPV 71%, NPV 82%, and accuracy 79%. In those with prior biliary stenting, the Miami Criteria resulted in Se 88%, Sp 36%, PPV 23%, NPV 93%, and accuracy 45%, while the Paris Classification resulted in Se 63%, Sp 73%, PPV 31%, NPV 91%, and accuracy 71%. The kappa statistic was 0.56.

CONCLUSION

The Paris Classification improved specificity and accuracy of biliary stricture classification in those who had been previously stented and decreased the rate of misclassification of benign strictures as malignant.

The efficacy of biliary and serum macrophage inhibitory cytokine-1 for diagnosing biliary tract cancer

The serum macrophage inhibitory cytokine-1 (MIC-1) levels are elevated in some inflammatory conditions and cancers. We thus compared the levels of biliary and serum MIC-1 and conventional tumour markers between 23 biliary tract cancer (BTC) patients (malignant group) and 29 benign biliary disease patients (benign group) and found that all markers were significantly elevated in the malignant group. The levels of two markers were higher in early BTC (Stage I/II, n = 15) than in the benign group: biliary MIC-1 [12 (0-2153) vs. 678 (0-4429) pg/ml, P < 0.01] and serum CA19-9 [13 (2-15,682) vs. 45.1 (2-10,478) U/ml, P = 0.02]. A receiver operating characteristic curve analysis revealed that the area under the curve for biliary MIC-1 was greater than that for serum CA19-9 (0.77 vs. 0.73). The cut-off value for biliary MIC-1 in diagnosing early BTC was 581.6 pg/ml, and this value yielded a sensitivity, specificity and accuracy of 71.4%, 82.8%, and 79.1%, respectively. The sensitivity of biliary MIC-1 for diagnosing early BTC was superior to that of biliary cytology (71.4% vs. 8.33%, P < 0.01), and the combination of serum MIC-1 with CA19-9 (cut-off value = 4021.2 pg/ml, 42.4 U/ml) was useful for screening BTC (sensitivity = 82.6%, specificity = 72.4%). In conclusion, biliary MIC-1 can effectively diagnose early BTC.

The Wire-Grasping Method as a New Technique for Forceps Biopsy of Biliary Strictures: A Prospective Randomized Controlled Study of Effectiveness

Background/Aims

Transpapillary forceps biopsy is an effective diagnostic technique in patients with biliary stricture. This prospective study aimed to determine the usefulness of the wire-grasping method as a new technique for forceps biopsy.

Methods

Consecutive patients with biliary stricture or irregularities of the bile duct wall were randomly allocated to either the direct or wire-grasping method group. In the wire-grasping method, forceps in the duodenum grasps a guide-wire placed into the bile duct beforehand, and then, the forceps are pushed through the papilla without endoscopic sphincterotomy. In the direct method, forceps are directly pushed into the bile duct alongside a guide-wire. The primary endpoint was the success rate of obtaining specimens suitable for adequate pathological examination.

Results

In total, 32 patients were enrolled, and 28 (14 in each group) were eligible for analysis. The success rate was significantly higher using the wire-grasping method than the direct method (100% vs 50%, p=0.016). Sensitivity and accuracy for the diagnosis of cancer were comparable in patients with the successful procurement of biopsy specimens between the two methods (91% vs 83% and 93% vs 86%, respectively).

Conclusions

The wire-grasping method is useful for diagnosing patients with biliary stricture or irregularities of the bile duct wall.

Diagnostic performance of a new endoscopic scraper for malignant biliary strictures: a multicenter prospective study

BACKGROUND AND AIMS

The efficacy of ERCP for histologic diagnosis of malignant biliary strictures is disappointingly low. The aim of this study was to investigate the diagnostic performance of a newly developed endoscopic device with scraping loops in combination with conventional biopsy forceps.

METHODS

We performed a multicenter single-arm prospective study. Between February 2013 and December 2014, 123 patients with suspected malignant biliary strictures were enrolled in the study. The new device and conventional biopsy forceps were applied for histologic diagnosis by ERCP. The primary outcome was to evaluate cancer detectability by biopsy forceps, the new device, and their combined use.

RESULTS

Of the 123 patients, 119 were diagnosed with a malignant stricture. Sufficient samples were collected in 83.7% (103/123), 93.5% (115/123), and 95.9% (118/123) of patients using biopsy forceps, the new device, and their combination, respectively. Cancer detectability of forceps biopsy, the new device, and their combination were 51.3% (61/119), 64.7% (77/119), and 74.8% (89/119), respectively. The new device had a significantly higher sample yield and cancer detectability than biopsy forceps (P < .01 and P = .018, respectively, McNemar test). Complementary use of the new device with biopsy forceps demonstrated a significantly additive effect in both sample yield and cancer detection (P < .01 each, McNemar test). The new device detected 48.3% (28/58) of cancers that were not diagnosed as malignant by biopsy forceps.

CONCLUSIONS

The new endoscopic scraper demonstrated a large sample yield and high cancer detectability. It could be a first-line tissue-sampling device for biliary strictures. (University Hospital Medical Information Network Clinical Trial Registry [UMIN-CTR] (http://www.umin.ac.jp/ctr/index.htm) registration number: UMIN000009895.).

Endoscopic Evaluation in the Workup of Pancreatic Cancer

Early diagnosis and accurate staging of pancreatic cancer is very important to plan optimal management strategy. Endoscopy plays an important role in the diagnosis and management of pancreatic cancer. Endoscopic ultrasound imaging (EUS) is the most sensitive modality for diagnosis, especially for small pancreatic tumors; it also allows tissue acquisition for histological diagnosis. Computed tomography scanning and EUS play complementary roles in staging and are comparable in determining resectability. Endoscopic retrograde cholangiopancreatography allows tissue sampling but is limited to palliative biliary drainage in most cases. In this article, we review the role of endoscopy in the diagnosis and management of pancreatic adenocarcinoma, with special emphasis on the use of endoscopic ultrasound and endoscopic retrograde cholangiopancreatography (ERCP).

The endoscopist's role in the diagnosis and management of pancreatic cancer

Pancreatic cancer remains one of the most lethal malignancies with little improvement in survival over the past several decades in spite of advances in imaging, risk factor identification, surgical technique and chemotherapy. This disappointing outcome is mainly due to failures to make an early diagnosis. In fact, the majority of the patients present with inoperable advanced stages of the disease. Though some of the new tumor markers are promising, we are still in search of the one that has a high sensitivity and accuracy, yet is inexpensive and easy to obtain. The paradigm of management has shifted from up-front surgery followed by adjuvant chemotherapy to neoadjuvant chemoradiation followed by surgery, especially for borderline resectable cancers and even for some resectable cancers. In this article, we will critically assess the limitations of tumor markers and review the advancements in endoscopic techniques in the management of pancreatic cancer.

Detection of benign hilar bile duct stenoses - A retrospective analysis in 250 patients with suspicion of Klatskin tumour

Introduction

The aim of this study was to identify clinical, laboratory and radiological parameters to distinguish benign from malignant stenoses of the proximal bile duct.

Methods

Between 1997 and 2011, 250 patients were referred to our clinic with hilar bile duct stenoses suspicious for Klatskin tumour. Medical histories, clinical data, pre-interventional laboratory tests, imaging findings, as well as therapeutic approach and patient outcome were compared to final histological results. All data were retrieved from our prospectively maintained database and analysed retrospectively.

Results

We found benign bile duct lesions in 34 patients (13.6%). Among the entire study population, uni- and multivariate analyses of 18 clinicopathological parameters revealed that patient age, serum alkaline phosphatase, tumour marker CA19-9 and presence of tumour mass in computed tomography were independent predictors for malignant biliary stenoses (p < 0.05). Receiver operator characteristic curve showed that a CA19-9 serum level of 61.2 U/ml or more has a sensitivity, specificity and diagnostic accuracy for predicting the malignant nature of the hilar biliary stenoses of 74.6%, 80.0% and 83.5%, respectively. Surgical resection could be avoided by preoperative work-up and surgical exploration in 10 out of 34 patients with benign lesions. Rates of major liver resections performed were 66.7% in the benign lesion group and 90.7% in the Klatskin tumour group.

Conclusion

Despite improvements of preoperative diagnostics, it remains difficult to differentiate between benign and malignant hilar bile duct stenosis. Even explorative laparotomy was not able to safely exclude Klatskin tumour in all cases and therefore major liver resection was inevitable.

•

Identification of clinical, laboratory and radiological parameters to distinguish benign from malignant strictures of the proximal bile duct.

•

Retrospective analysis in 250 patients with suspicion of Klatskin tumour.

•

Patient age, alkaline phosphatase, CA19-9 and presence of tumour mass in CT scan are predictors for malignant stenosis of the proximal bile duct.

Transpapillary biliary biopsy for malignant biliary strictures: comparison between cholangiocarcinoma and pancreatic cancer

BACKGROUND

Tissue sampling for biliary stricture is important for differential diagnosis and further treatment. This study aims to assess the differences of transpapillary biliary biopsy for malignant biliary strictures between cholangiocarcinoma and pancreatic cancer.

METHODS

From January 2010 to December 2013, we retrospectively studied 79 patients who suffered from biliary strictures and received transpapillary forceps biopsy after sphincterotomy for tissue sampling. The diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of forceps biopsy were calculated in all cases for both cholangiocarcinoma and pancreatic cancer patients. Possible factors that distinguish malignant strictures from benign strictures and which could affect the accuracy of tissue sampling were analyzed.

RESULTS

There are 65 malignant and 14 benign biliary stricture patients enrolled. The malignant group has a significantly higher serum bilirubin level than the benign group, but age, clinical presentation, level of serum carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, and alkaline phosphatase are not. The sensitivity, specificity, PPV, and NPV of forceps biopsy for biliary stricture are 53.85, 100, 100, and 31.82%, respectively. The cholangiocarcinoma group has a higher sensitivity (73.53 versus 29.17%, p < 0.001), older age, lower CA 19-9 level, and more common hepatic duct strictures than the pancreatic group. The age, serum CEA, CA 19-9 and the alkaline phosphatase level, serum bilirubin level >10 mg/dL, tissue sampling ≧3 are not significant factors affecting diagnostic accuracy in forceps biopsy for pancreatobiliary strictures. There is neither major bleeding nor perforation in our study.

CONCLUSIONS

Transpapillary forceps biopsy of biliary strictures after sphincterotomy for tissue sampling is safe and a significantly higher sensitive method in cholangiocarcinoma but not in pancreatic cancer.

Diagnostic Utility of Endoscopic Retrograde Cholangiography/Intraductal Ultrasound (ERC/IDUS) in Distinguishing Malignant from Benign Bile Duct Obstruction

BACKGROUND AND AIM

Accurately differentiating malignant diseases from benign ones in patients having bile duct obstruction is of significant importance and remains a major clinical problem. This study investigated the diagnostic yield of endoscopic retrograde cholangiography/intraductal ultrasound (ERC/IDUS) in distinguishing malignant from benign bile duct obstruction and assessed some image findings from ERC/IDUS which might be useful in differentiation.

METHODS

From January 2008 to January 2015, patients who underwent ERC/IDUS for bile duct obstruction were enrolled. Patient's ERC/IDUS diagnosis was compared with the final diagnosis determined by pathologic findings and/or clinical outcome of follow-up.

RESULTS

One hundred and ninety-three patients with bile duct obstruction were included. IDUS correctly identified 94 of 97 malignant diseases and 76 of 96 benign diseases with sensitivity, specificity, and accuracy rate of 96.91, 79.17, and 88.08 %, respectively. Additionally, the accuracy rate of IDUS for diagnosis of proximal bile duct obstruction was higher than that of distal bile duct obstruction (98.08 vs. 82.73 %, p = 0.006). Besides, there was a significant difference in the length at the obstruction site between benign and malignant diseases (13.76 ± 7.37 vs. 19.97 ± 11.37 mm, p < 0.001) as well as thickness of bile duct wall at the site of obstruction (3.06 ± 0.92 vs. 7.03 ± 3.70 mm, p = 0.008). Biliary wall thickness >7 mm without extrinsic compression had a positive predictive value (PPV) of 100 % for including malignancy, while length ≧20 mm demonstrated a PPV of 93.44 %.

CONCLUSIONS

ERC/IDUS is effective in distinguishing malignant from benign bile duct obstruction, thus helping in further clinical management.

Diagnostic yield of EUS-guided FNA for malignant biliary stricture: a systematic review and meta-analysis

BACKGROUND AND AIMS

EUS-guided FNA (EUS-FNA) is increasingly being used for tissue diagnosis of extrahepatic biliary strictures. The aim of this study was to determine the diagnostic yield of EUS-FNA in malignant biliary strictures.

METHODS

A comprehensive literature review was carried out by 2 reviewers for studies evaluating the accuracy of EUS-FNA in biliary stricture. A meta-analysis was performed to determine the pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio for EUS-FNA of extrahepatic biliary stricture. A Quality Assessment of Diagnostic Accuracy Studies questionnaire was used to assess the quality of the selected studies. Several sensitivity analyses were performed to assess the effect of the quality of the studies on the accuracy of the final results of the meta-analysis.

RESULTS

Twenty studies involving 957 patients met inclusion criteria and were included in the meta-analysis. The pooled sensitivity and specificity of EUS-FNA for diagnosis of malignant biliary stricture were 80% (95% confidence interval [CI], 74%-86%), and 97% (95% CI, 94%-99%), respectively. The pooled positive likelihood ratio was 12.35 (95% CI, 7.37-20.72), and the negative likelihood ratio was 0.26 (95% CI, 0.18-0.38). The pooled diagnostic odds ratio for diagnosing a malignant biliary stricture was 70.53 (95% CI, 38.62-128.82). The area under the receiver-operating characteristic curve was 0.97. Sensitivity analyses showed that the quality of the included studies did not affect the accuracy of the final results of the meta-analysis.

CONCLUSION

This meta-analysis demonstrates that EUS-FNA is sensitive and highly specific for diagnosing malignancy in biliary strictures. Further studies are needed to compare EUS--FNA with emerging methods including cholangioscopy-guided biopsy and laser endomicroscopy.

Evaluation of indeterminate biliary strictures

Biliary strictures frequently present a diagnostic challenge during pre-operative evaluation to determine their benign or malignant nature. A variety of benign conditions, such as primary sclerosing cholangitis (PSC) and IgG4-related sclerosing cholangitis, frequently mimic malignancies. In addition, PSC and other chronic biliary diseases increase the risk of cholangiocarcinoma and so require ongoing vigilance. Although traditional methods of evaluation including imaging, detection of circulating tumour markers, and sampling by endoscopic ultrasound and endoscopic retrograde cholangiopancreatography have a high specificity, they suffer from low sensitivity. Currently, up to 20% of biliary strictures remain indeterminate after pre-operative evaluation and necessitate surgical intervention for a definitive diagnosis. The discovery of novel biomarkers, new imaging modalities and advanced endoscopic techniques suggests that a multimodality approach might lead to better diagnostic accuracy.

Diagnosing Biliary Malignancy

The most common malignant causes of biliary strictures are pancreatic cancer and cholangiocarcinoma. Differentiating between malignant and benign causes of biliary strictures has remained a clinical challenge. Endoscopic retrograde cholangiopancreatography (ERCP) remains the mainstay and first-line method of tissue diagnosis but has a poor diagnostic yield. This article reviews the causes of biliary strictures, the initial clinical evaluation of biliary obstruction, the diagnostic yield of ERCP-based sampling methods, the role of newer tools in the armamentarium for evaluating strictures, and ways to address the ongoing challenge of stricture evaluation in patients with primary sclerosing cholangitis.

The Role of Endoscopy in the Diagnosis and Management of Cholangiocarcinoma

Cholangiocarcinomas (CCAs) are associated with poor overall survival, and majority of the tumors are unresectable at the time of diagnosis. Early diagnosis at a resectable stage is essential for improved outcomes. Noninvasive imaging plays an important role in evaluating patients with biliary obstruction, but is limited due to the lack of tissue sampling and in many cases due to the absence of a mass, especially for extrahepatic CCAs. Endoscopic diagnosis is needed in majority of patients with CCA and the diagnostic yield depends on the tumor location as well as the expertise and experience of the endoscopist. Endoscopic retrograde cholangiopancreatography and endoscopic ultrasound remain the most common endoscopic diagnostic tools although newer technologies including fluorescence in situ hybridization, single-operator cholangioscopy, confocal laser endomicroscopy, and intraductal ultrasound are being increasing used. Traditionally, the role of endoscopy has been mainly palliative and limited to biliary drainage in patients with obstructive jaundice, however, newer treatment options like photodynamic therapy and radiofrequency ablation have shown promise toward improved patient survival. Multidisciplinary approach that involves medical oncology, gastroenterology, radiology, and surgical oncology teams is imperative for improved outcomes. In this review, we will first review the diagnostic approach to CCAs including imaging and endoscopic methods followed by a discussion of different endoscopic techniques in management of patients after a diagnosis of CCA.

Use of probe-based confocal laser endomicroscopy (pCLE) in gastrointestinal applications. A consensus report based on clinical evidence

BACKGROUND

Probe-based confocal laser endomicroscopy (pCLE) provides microscopic imaging during an endoscopic procedure. Its introduction as a standard modality in gastroenterology has brought significant progress in management strategies, affecting many aspects of clinical care and requiring standardisation of practice and training.

OBJECTIVE

This study aimed to provide guidance on the standardisation of its practice and training in Barrett's oesophagus, biliary strictures, colorectal lesions and inflammatory bowel diseases.

METHODS

Initial statements were developed by five group leaders, based on the available clinical evidence. These statements were then voted and edited by the 26 participants, using a modified Delphi approach. After two rounds of votes, statements were validated if the threshold of agreement was higher than 75%.

RESULTS

Twenty-six experts participated and, among a total of 77 statements, 61 were adopted (79%) and 16 were rejected (21%). The adoption of each statement was justified by the grade of evidence.

CONCLUSION

pCLE should be used to enhance the diagnostic arsenal in the evaluation of these indications, by providing microscopic information which improves the diagnostic performance of the physician. In order actually to implement this technology in the clinical routine, and to ensure good practice, standardised initial and continuing institutional training programmes should be established.

Probe-based confocal laser endomicroscopy for indeterminate biliary strictures: refinement of the image interpretation classification

Background. Accurate diagnosis and clinical management of indeterminate biliary strictures are often a challenge. Tissue confirmation modalities during Endoscopic Retrograde Cholangiopancreatography (ERCP) suffer from low sensitivity and poor diagnostic accuracy. Probe-based confocal laser endomicroscopy (pCLE) has been shown to be sensitive for malignant strictures characterization (98%) but lacks specificity (67%) due to inflammatory conditions inducing false positives. Methods. Six pCLE experts validated the Paris Classification, designed for diagnosing inflammatory biliary strictures, using a set of 40 pCLE sequences obtained during the prospective registry (19 inflammatory, 6 benign, and 15 malignant). The 4 criteria used included (1) multiple thin white bands, (2) dark granular pattern with scales, (3) increased space between scales, and (4) thickened reticular structures. Interobserver agreement was further calculated on a separate set of 18 pCLE sequences. Results. Overall accuracy was 82.5% (n = 40 retrospectively diagnosed) versus 81% (n = 89 prospectively collected) for the registry, resulting in a sensitivity of 81.2% (versus 98% for the prospective study) and a specificity of 83.3% (versus 67% for the prospective study). The corresponding interobserver agreement for 18 pCLE clips was fair (k = 0.37). Conclusion. Specificity of pCLE using the Paris Classification for the characterization of indeterminate bile duct stricture was increased, without impacting the overall accuracy.

Probe-based confocal laser endomicroscopy in the pancreatic duct provides direct visualization of ductal structures and aids in clinical management

BACKGROUND

Confocal endomicroscopy provides real-time evaluation of various sites and has been used to provide detailed endomicroscopic imaging of the biliary tree. We aimed to evaluate the feasibility and utility of probe-based confocal laser endomicroscopy of the pancreatic duct as compared to cytologic and histologic results in patients with indeterminate pancreatic duct strictures.

METHODS

Retrospective data on patients with indeterminate pancreatic strictures undergoing endoscopic retrograde cholangiopancreatography (ERCP) and confocal endomicroscopy were collected from two tertiary care centres. Real-time confocal endomicroscopy images were obtained during ERCP and immediate interpretation according to the Miami Classification was performed.

RESULTS

18 patients underwent confocal endomicroscopy for evaluation of pancreatic strictures from July 2011 to December 2012. Mean pancreatic duct size was 4.2mm (range 2.2-8mm). Eight cases were interpreted as benign, 4 as malignant, 4 suggestive of intraductal papillary mucinous neoplasms, and 2 appeared normal. Cytology/histopathology for 15/16 cases showed similar results to confocal endomicroscopy interpretation. Kappa coefficient of agreement between cyto/histopathology and confocal endomicroscopy was 0.8 (p=0.0001). Pancreatic confocal endomicroscopy changed management in four patients, changing the type of surgery from total pancreatectomy to whipple.

CONCLUSIONS

Confocal endomicroscopy is effective in assisting with diagnosis of indeterminate pancreatic duct strictures as well as mapping of abnormal pancreatic ducts prior to surgery.