Role of SpyGlass peroral cholangioscopy in the evaluation of indeterminate biliary lesions

Artificial intelligence in endoscopy: Overview, applications, and future directions

Since the emergence of artificial intelligence (AI) in medicine, endoscopy applications in gastroenterology have been at the forefront of innovations. The ever-increasing number of studies necessitates the need to organize and classify applications in a useful way. Separating AI capabilities by computer aided detection (CADe), diagnosis (CADx), and quality assessment (CADq) allows for a systematic evaluation of each application. CADe studies have shown promise in accurate detection of esophageal, gastric and colonic neoplasia as well as identifying sources of bleeding and Crohn's disease in the small bowel. While more advanced CADx applications employ optical biopsies to give further information to characterize neoplasia and grade inflammatory disease, diverse CADq applications ensure quality and increase the efficiency of procedures. Future applications show promise in advanced therapeutic modalities and integrated systems that provide multimodal capabilities. AI is set to revolutionize clinical decision making and performance of endoscopy.

Improved fluoroscopy-guided biopsies in the diagnosis of indeterminate biliary strictures: a multi-center retrospective study

To evaluate the diagnostic accuracy of improved fluoroscopy-guided biopsies for indeterminate biliary strictures (IBDS). A multi-center retrospective study was performed. Patients with IBDS who underwent digital single-operator cholangioscopy (DSOC) and improved fluoroscopy-guided biopsies procedures were included. The individual sensitivity, specificity, and accuracy were analyzed. A total of 67 patients were enrolled in this multi-center retrospective study. The DSOC and improved fluoroscopy-guided biopsies procedures were successfully performed in all cases (100%). The sensitivity, specificity, and accuracy values were 83.3%, 89.5%, and 85.1% for DSOC visual impression; 95.8%, 94.7%, and 95.5% for improved fluoroscopy-guided biopsies procedures, respectively. The sensitivity and accuracy of improved fluoroscopy-guided biopsies were significantly higher compared with DSOC visual impression. Four patients (6.0%, 4/67) occurred adverse events after the procedures. Improved fluoroscopy-guided biopsies had a high diagnostic accuracy of IBDS diagnosis.

Digital single-operator cholangioscopy interobserver study using a new classification: the Mendoza Classification (with video)

BACKGROUND AND AIMS

Digital single-operator cholangioscopy (DSOC) allows direct visualization of the biliary tree for evaluation of biliary strictures. Our objective was to assess the interobserver agreement (IOA) of DSOC interpretation for indeterminate biliary strictures using newly refined criteria.

METHODS

Fourteen endoscopists were asked to review an atlas of reference clips and images of 5 criteria derived from expert consensus. They then proceeded to score 50 deidentified DSOC video clips based on the visualization of tortuous and dilated vessels, irregular nodulations, raised intraductal lesions, irregular surface with or without ulcerations, and friability. The endoscopists then diagnosed the clips as neoplastic or non-neoplastic. Intraclass correlation (ICC) analysis was done to evaluate inter-rater agreement for both criteria sets and final diagnosis.

RESULTS

Clips of 41 malignant lesions and 9 benign lesions were scored. Three of 5 revised criteria had almost perfect agreement. ICC was almost perfect for presence of tortuous and dilated vessels (.86), raised intraductal lesions (.90), and presence of friability (.83); substantial agreement for presence of irregular nodulations (.71); and moderate agreement for presence of irregular surface with or without ulcerations (.44). The diagnostic ICC was almost perfect for neoplastic (.90) and non-neoplastic (.90) diagnoses. The overall diagnostic accuracy using the revised criteria was 77%, ranging from 64% to 88%.

CONCLUSIONS

The IOA and accuracy rate of DSOC using the new Mendoza criteria shows a significant increase of 16% and 20% compared with previous criteria. The reference atlas helps with formal training and may improve diagnostic accuracy. (Clinical trial registration number: NCT02166099.).

Digital Single-operator Cholangioscopy (DSOC) Improves Interobserver Agreement (IOA) and Accuracy for Evaluation of Indeterminate Biliary Strictures: The Monaco Classification

BACKGROUND

Visual characteristics seen during digital single-operator cholangioscopy (DSOC) have not been validated. The aim of this 2-phase study was to define terminology by consensus for the visual diagnosis of biliary lesions to develop a model for optimization of the diagnostic performance of DSOC.

MATERIALS AND METHODS

In phase 1 (criteria identification), video-cholangioscopy clips were reviewed by 12 expert biliary endoscopists, who were blinded to the final diagnosis. Visual criteria were consolidated into the following categories: (1) stricture, (2) lesion, (3) mucosal features, (4) papillary projections, (5) ulceration, (6) abnormal vessels, (7) scarring, (8) pronounced pit pattern.During the second phase (validation), 14 expert endoscopists reviewed DSOC (SpyGlass DS, Boston Scientific) clips using the 8 criteria to assess interobserver agreement (IOA) rate.

RESULTS

In phase 1, consensus for visual findings were categorized into 8 criteria titled the "Monaco Classification." The frequency of criteria were: (1) presence of stricture-75%, (2) presence of lesion type-55%, (3) mucosal features-55%, (4) papillary projections-45%, (5) ulceration-42.5%, (6) abnormal vessels-10%, (7) scarring-40%, and (8) pronounced pit pattern-10%. The accuracy on final diagnosis based on visual impression alone was 70%.In phase 2, the IOA rate using Monaco Classification criteria ranged from slight to fair. The presumptive diagnosis IOA was fair (κ=0.31, SE=0.02), and overall diagnostic accuracy was 70%.

CONCLUSIONS

The Monaco classification identifies 8 visual criteria for biliary lesions on single-operator digital cholangioscopy. Using the criteria, the IOA and diagnostic accuracy rate of DSOC is improved compared with prior studies.

Peroral Cholangioscopy-Guided Targeted Biopsy versus Conventional Endoscopic Transpapillary Forceps Biopsy for Biliary Stricture with Suspected Bile Duct Cancer

Background: The recent improvement of peroral cholangioscopy (POCS) maneuverability has enabled the precise, targeted biopsy of bile duct lesions under direct cholangioscopic vision. However, as only small-cup biopsy forceps can pass through the scope channel, the resulting small sample size may limit the pathological diagnosis of biopsy specimens. This study compared the diagnostic abilities of POCS-guided biopsy and conventional fluoroscopy-guided biopsy for bile duct cancer. Method: This multicenter, retrospective cohort study included patients exhibiting bile duct stricture with suspected cholangiocarcinoma in whom POCS-guided and fluoroscopy-guided biopsies were performed in the same session. The primary endpoint was the diagnostic sensitivity for malignancy. The size and quality of the biopsy specimens were also compared. Result: A total of 59 patients were enrolled. The sensitivity of POCS-guided biopsy was similar to that of fluoroscopy-guided biopsy (54.0% and 64.0%, respectively). However, when the modalities were combined, the sensitivity increased to 80.0%. The mean specimen size from POCS-guided biopsy was significantly smaller than that from fluoroscopy-guided biopsy. The specimen quality using fluoroscopy-guided biopsy was also better than that using POCS-guided biopsy. Conclusions: The diagnostic sensitivity of POCS-guided biopsy is still insufficient, mainly because of the limited specimen quantity and quality. Therefore, conventional fluoroscopy-guided biopsy would be helpful to improve diagnostic sensitivity.

[Oral cholangioscopy for biliary system diseases]

OBJECTIVE

To improve the results of treatment of obstructive jaundice by using of oral cholangioscopy.

MATERIAL AND METHODS

There were 321 patients with obstructive jaundice between October 2020 and November 2021. Of these, cholangioscopy (SpyGlass video system) was used in 18 patients. Patients were divided into two groups: group 1 (n=9) - malignant biliary strictures; group 2 (n=9) - choledocholithiasis with large calculi (≥1.2 cm). At admission, all patients underwent laboratory and instrumental examination. In the first group, bilioduodenal stenting with plastic stents 7 and 10 Fr in diameter, 7 to 12 cm long or self-expanding nitinol stents 0.8-1.0 cm in diameter, 6 to 10 cm long was carried out. Patients with large calculi underwent targeted laser lithotripsy under endoscopic control until formation of 1-cm fragments. These fragments were removed using a lithoextraction balloon and Dormia basket.

RESULTS

Cholangioscopy (SpyGlass system) was performed within 2 days after admission. In group 1, tumor tissue overgrowths were found during cholangioscopy. Five out of 9 (55.6%) patients underwent bilioduodenal stenting for adequate biliary drainage. Of these, 4 (44.5%) patients developed acute edematous pancreatitis on the first postoperative day. This complication regressed after 3-4 days under therapy. Four (44.5%) patients died from cancer-related multiple organ failure. In group 2, cholangioscopy effectively visualized the calculus and ensured its destruction by laser contact lithotripsy. Intraoperative and postoperative complications were not revealed in both groups.

CONCLUSION

SpyGlass system is effective and safe for diagnosis and treatment in 100% of patients with extrahepatic biliary strictures and/or large calculi.

Diagnostic accuracy and interobserver agreement of digital single-operator cholangioscopy for indeterminate biliary strictures

BACKGROUND AND AIMS

Digital single-operator cholangioscopy (d-SOC) with cholangioscopic biopsy sampling has shown promise in the evaluation of indeterminate biliary strictures. Some studies have suggested higher sensitivity for visual impression compared with biopsy sampling, although assessors were not blinded to previous investigations. We aimed to investigate the diagnostic accuracy and interobserver agreement (IOA) of d-SOC in the visual appraisal of biliary strictures when blinded to additional information.

METHODS

A multicenter, international cohort study was performed. Cholangioscopic videos in patients with a known final diagnosis were systematically scored. Pseudonymized videos were reviewed by 19 experts in 2 steps: blinded for patient history and investigations and unblinded.

RESULTS

Forty-four high-quality videos were reviewed of 19 benign and 25 malignant strictures. The sensitivity and specificity for the diagnosis of malignancy was 74.2% and 46.9% (blinded) and 72.7% and 62.5% (unblinded). Cholangioscopic certainty of a malignant diagnosis led to overdiagnosis (sensitivity, 90.6%; specificity, 33%), especially if no additional information was provided. The IOA for the presence of malignancy was fair for both assessments (Fleiss' κ = .245 [blinded] and κ = .321 [unblended]). For individual visual features, the IOA ranged from slight to moderate for both assessments (κ = .059-.400 vs κ = .031-.452).

CONCLUSIONS

This study showed low sensitivity and specificity for blinded and unblinded d-SOC video appraisal of indeterminate biliary strictures, with considerable interobserver variation. Although reaching a consensus on the optical features of biliary strictures remains important, optimizing visually directed biopsy sampling may be the most important role of cholangioscopy in biliary stricture assessment.

Diagnostic Accuracy and Therapeutic Efficacy of Digital Single-Operator Cholangioscopy for Biliary Lesions and Stenosis

BACKGROUND/AIMS

Digital single-operator cholangioscopy (dSOC) has revolutionized bile duct visualization. Interventions like electrohydraulic or laser lithotripsy, inspection of suspicious areas, and targeted biopsies have become possible quick and easy. One main indication for dSOC remains the evaluation of indeterminate biliary strictures.

OBJECTIVE AND METHODS

We analyzed 180 consecutive dSOCs procedures performed in a high-volume tertiary center to evaluate sensitivity, specificity as well as positive and negative predictive values (PPV and NPV) for indeterminate strictures. Furthermore, technical success and complications were analyzed.

RESULTS

In 92-97%, the region of interest was reached and successfully visualized. In 83-100%, targeted biopsies were obtained from the suspicious area. Only the distal bile duct was less successful with only 84 and 62%, respectively. In general, dSOC procedures were safe. Cholangitis was the main complication. Regarding the diagnostic accuracy of dSOC of indeterminate biliary strictures, we found a sensitivity of 0.87 and specificity of 0.88, over all. Within the whole cohort, the investigators' assessment directly after dSOC had a PPV of 0.63 and a NPV of 0.97. In patients with biliary lesions or stenosis suspicious for malignancy, the dSOC-based visual diagnosis revealed a very high diagnostic accuracy with sensitivity and specificity of 1.0 (95% CI 0.86-1.0) and 0.76 (95% CI 0.56-0.9) with a PPV of 0.77 (95% CI 0.59-0.9) and a high NPV of 1.0 (95% CI 0.85-1.0).

CONCLUSIONS

Our study demonstrates that dSOC has a high diagnostic accuracy as well as a favorable safety profile. Therefore, dSOC should be discussed as standard of care during endoscopic retrograde cholangiography for indeterminate biliary lesions.

Diagnostic value of peroral cholangioscopy in addition to computed tomography for indeterminate biliary strictures

BACKGROUND

Peroral cholangioscopy (POCS) has been used to overcome the difficulty in diagnosing indeterminate biliary stricture or tumor spread. However, the value of adding POCS to computed tomography (CT) remains unclear. Our aim was to evaluate the diagnostic value of adding POCS to CT for indeterminate biliary stricture and tumor spread by interpretation of images focusing on the high diagnostic accuracy of visual findings in POCS.

METHODS

We retrospectively identified 52 patients with biliary stricture who underwent endoscopic retrograde cholangiography (ERC) at our institution between January 2013 and December 2018. Two teams, each composed of an expert endoscopist and surgeon, performed the interpretation independently, referring to the CT findings of the radiologist. The CT + ERC + POCS images (POCS group) were evaluated 4 weeks after the evaluation of CT + ERC images (CT group). A 5-point scale (1: definitely benign to 5: definitely malignant) was used to determine the confident diagnosis rate, which was defined as an evaluation value of 1 or 5. Tumor spread was also evaluated.

RESULTS

In the evaluation of 45 malignant diagnoses, the score was significantly closer to 5 in the POCS group than in the CT group in both teams (P < 0.001). The confident diagnosis rate was significantly higher for the POCS group (92% and 73%) than for the CT group (25% and 12%) in teams 1 and 2, respectively (P < 0.001). We found no significant difference in diagnostic accuracy for tumor spread between the groups.

CONCLUSION

Visual POCS findings confirmed the diagnosis of biliary strictures. POCS was useful in cases of indefinite diagnosis of biliary strictures by CT.

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.

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.

Artificial intelligence in biliopancreatic endoscopy: Is there any role?

Artificial intelligence (AI) research in endoscopy is being translated at rapid pace with a number of approved devices now available for use in luminal endoscopy. However, the published literature for AI in biliopancreatic endoscopy is predominantly limited to early pre-clinical studies including applications for diagnostic EUS and patient risk stratification. Potential future use cases are highlighted in this manuscript including optical characterisation of strictures during cholangioscopy, prediction of post-ERCP acute pancreatitis and selective biliary duct cannulation difficulty, automated report generation and novel AI-based quality key performance metrics. To realise the full potential of AI and accelerate innovation, it is crucial that robust inter-disciplinary collaborations are formed between biliopancreatic endoscopists and AI researchers.

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.

New staining method using methionyl-tRNA synthetase 1 antibody for brushing cytology of bile duct cancer

BACKGROUND AND AIMS

Identifying malignant biliary strictures using endobiliary brushing cytology specimens is important for treatment decision-making and prognosis prediction. The sensitivity of brushing cytology specimens based on Papanicolaou (Pap) staining is low, which hampers accurate diagnosis of indeterminate strictures. Here, we assessed the diagnostic value of immunohistochemical (IHC) and immunofluorescence (IF) staining for methionyl-tRNA synthetase 1 (MARS1).

METHODS

Endobiliary brushing cytology specimens were obtained during ERCP from 80 patients with an extrahepatic biliary stricture. Pap and MARS1 IF staining were performed on liquid-based cytology slides derived from these specimens. Sections of bile duct adenocarcinoma and normal bile duct tissue were obtained from 45 patients who underwent surgery for malignant biliary stricture, and MARS1 levels were evaluated by IHC staining.

RESULTS

MARS1 IF staining was applied to brushing cytology specimens, and the results showed strong signals in malignant biliary structures but not in the negative for malignancy specimens. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 70.4%, 96.2%, 97.4%, 56.8%, and 78.8%, respectively, for conventional Pap staining and 98.1%, 96.1%, 98.1%, 96.2%, and 97.5%, respectively, for MARS1 IF (P < .0001). When IHC staining was used, MARS1 was detected in 45 bile duct adenocarcinoma sections but not in 15 normal bile duct sections. Moreover, MARS1 mRNA and protein levels were significantly higher in bile duct adenocarcinoma sections according to polymerase chain reaction and Western blot, respectively.

CONCLUSIONS

The high sensitivity and accuracy of MARS1 IF staining enabled detection of malignancy in patients with indeterminate biliary stricture. Further prospective studies are needed to validate our findings. (Clinical trial registration number: KCT 0003285.).

Use of SpyGlass for peroral cholangioscopy in the diagnosis and treatment of hepatobiliary diseases in over five years follow-up: A single centre experience

BACKGROUND/AIMS

The use of cholangioscopy for the diagnosis and treatment of hepatobiliary diseases is gradually becoming more common. We aimed to review our peroral cholangioscopy interventions, using the first-generation SpyGlass Direct Visualization System (SDVS) and summarize our experience in terms of procedures and results.

MATERIALS AND METHODS

Forty-one patients who underwent this procedure at our Gastroenterology Clinic between February 2010 and October 2014 were included in this study. Patients were monitored for a median (IQR) of 44 (range 38-72) months. Demographic characteristics of these patients, results of the radiological and biochemical evaluation performed prior to the procedure, cholangioscopy findings together with the data relating to the procedure, histopathological diagnosis, clinical findings and results, and their effects on patient prognosis were assessed.

RESULTS

In total, 41 patients underwent 46 cholangioscopy procedures. Of them, 21 (51.2%) were male. The most frequent clinical indications for cholangioscopy was the need to further investigate indeterminate stricture (n=16; 39%) and indeterminate filling defect (n=7; 17.1%). The procedure was considered successful in 39 patients with 41 (95.1%) receiving diagnostic and 33 (80.5%) receiving therapeutic benefits. The sensitivity and specificity for SVDS-guided biopsies and brush cytology were 80% and 87.5%; 26.6% and 75%, respectively. Complications related to the procedure occurred in a total of three patients (7.3%), two with cholangitis and one with perforation of gall bladder.

CONCLUSION

Our experience shows that cholangioscopy procedures, performed with SDVS, are clinically applicable and safe in the diagnosis and treatment of hepatobiliary diseases.

Biliary interventions using single-operator cholangioscopy

Cholangioscopy provides an opportunity to directly visualize the bile duct for diagnosing biliary lesions and for therapeutic interventions. Although there are different cholangioscopy techniques available, single-operator cholangioscopy has gained widespread acceptance as the standard technique for interventions in the biliary system because of its ease of use and widespread availability. Single-operator cholangioscopy can be used for both diagnostic and therapeutic indications in the biliary tract. Diagnostic cholangioscopy is used for direct evaluation of indeterminate bile duct strictures with biopsies, diagnosing filling defects in the bile ducts observed during endoscopic retrograde cholangiography (ERC) imaging, preoperative mapping of the precise location and extension of tumors of the biliary tract, and diagnosis of intraductal neoplasms. Therapeutic cholangioscopy is used for visually guided treatment of biliary stones that have failed extraction with conventional ERC techniques, residual or impacted stones by using intraductal lithotripsy, ablation of biliary tumors and for facilitation of guidewire advancement into selective intrahepatic ducts for adequate biliary drainage. In this review, we will focus on advances in the single-operator cholangioscopy techniques in the diagnosis and management of biliary disorders.

Peroral cholangioscopy with cholangioscopy-directed biopsies in the diagnosis of biliary malignancies: a systemic review and meta-analysis

BACKGROUND AND AIM

Accurate diagnosis is essential in the appropriate management of biliary strictures. Our aim is to evaluate the efficacy of cholangioscopy-directed biopsies in differentiating biliary intraductal malignancies from benign lesions.

MATERIALS AND METHODS

Articles were searched in Medline, PubMed, and Ovid journals. Pooling was performed by both fixed-effects and random-effects models. Only studies from which a 2×2 table could be constructed for true-positive, false-negative, false-positive, and true-negative values were included.

RESULTS

Initial search identified 2110 reference articles for peroral cholangioscopy; of these, 160 relevant articles were selected and reviewed. Data were extracted from 15 studies (N=539) that fulfilled the inclusion criteria. Pooled sensitivity of cholangioscopy-directed biopsies in diagnosing malignancy was 71.9% [95% confidence interval (CI): 66.1-77.1] and pooled specificity was 99.1% (95% CI: 96.9-99.9). The positive likelihood ratio of cholangioscopy-directed biopsies was 18.1 (95% CI: 9.1-35.8), whereas the negative likelihood ratio was 0.3 (95% CI: 0.2-0.4). The pooled diagnostic odds ratio was 71.6 (95% CI: 32.8-156.4). All the pooled estimates calculated by fixed-effects and random-effect models were similar. Summary receiver operating characteristic curves showed an area under the curve of 0.98. The χ heterogeneity for all the pooled accuracy estimates was 5.62 (P=0.96).

CONCLUSION

Peroral cholangioscopy with cholangioscopy-directed biopsies has a high specificity in differentiating intraductal malignancies from benign lesions. Cholangioscopy-directed biopsies should be strongly considered for biliary stricture evaluation.

The Role of Peroral Cholangioscopy in Evaluating Indeterminate Biliary Strictures

Biliary strictures are considered indeterminate when the initial radiologic evaluation and endoscopic retrograde cholangiopancreatography with brush cytology and/or forceps biopsy do not reveal diagnostic findings. Evaluation of these strictures is challenging and often requires a multidisciplinary approach and multiple procedures. Peroral cholangioscopy allows direct visualization of these lesions and targeted tissue acquisition using miniature biopsy forceps. In the past decade, there have been significant improvements in the field of cholangioscopy. These advances have allowed higher-quality image acquisition, easy setup, operation by a single operator, easy maneuverability, and excellent targeted tissue sampling performance. However, the interpretation of cholangioscopic visual findings remains challenging. In this review, we discuss the role of peroral cholangioscopy in the evaluation of indeterminate biliary strictures.

Clinical impact of digital cholangioscopy in management of indeterminate biliary strictures and complex biliary stones: a single-center study

Aims:

Endoscopic management of indeterminate strictures and complex stones remains a challenge, for which the latest generation single-operator digital cholangioscope (SpyGlass DS) has shown promising results. We aimed to study the clinical impact of single-operator digital cholangioscope at our tertiary academic center.

Methods:

We retrospectively reviewed all digital cholangioscopies performed from June 2015 to May 2018. Patient characteristics, procedure characteristics, and post-procedural patient outcomes were recorded.

Results:

A total of 50 patients (26 men, average age 61.4 years) underwent 67 procedures. Indications were biliary stones (21/50, 42%), strictures and primary sclerosing cholangitis surveillance (22/50, 46%), and miscellaneous (7/50, 14%). The average procedure time was 82 ± 29 min (99.5 min for stones and 74.2 min for strictures). Stone clearance was achieved in 19/21 (90.47%) cases, with electrohydraulic lithotripsy employed in 16/21 and repeat cholangioscopy necessary in 9/21. Malignant strictures (10) were differentiated from benign (12) in all cases both in patients with primary sclerosing cholangitis (9) and in those without (13), based on visual cholangioscopic features (sensitivity and specificity 100%), single-operator digital cholangioscope–directed biopsies (sensitivity 60% and specificity 100%), and brush cytology (sensitivity 37.5% and specificity 100%). Complications included one post-sphincterotomy bleeding and one post-procedural cholangitis despite antibiotic prophylaxis, but no procedure-related mortality.

Conclusion:

Single-operator digital cholangioscope had a high success rate and a low rate of complications for management of indeterminate strictures and difficult biliary stones. Visual cholangioscopic features of biliary strictures had excellent diagnostic accuracy, and targeted biopsies outperformed brush cytology. Early implementation of cholangioscopy for select indications leads to successful patient outcomes and reduces diagnostic delays, cost, and risks of repeat endoscopic retrograde cholangiopancreatographies.

Reliability and accuracy of a novel classification system using peroral cholangioscopy for the diagnosis of bile duct lesions

BACKGROUND

The aim of this study was to propose a novel, comprehensive, macroscopic classification for bile duct lesions.

METHODS

A two-stage protocol was designed. In Stage I, a retrospective study (September 2013 to September 2015) of patients with bile duct lesions detected by peroral cholangioscopy (POCS) was performed. A total of 315 images with at least 6 months of follow-up were recorded, analyzed, and correlated to histology, and were classified as non-neoplastic (one of three types, 1 - 3) or neoplastic (one of four types, 1 - 4) based on morphological and vascular patterns. In Stage II, a prospective, nonrandomized, double-blind study was performed from December 2015 to December 2016 to validate the proposed classification. Sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively), and positive and negative likelihood ratios (LR + and LR - , respectively) were calculated (gold standard: 6-month follow-up). Inter- and intraobserver agreement (kappa value, κ) among experts and non-experts were calculated.

RESULTS

171 patients were included (65 retrospective; 106 prospective). In Stage I, 28/65 cases were neoplastic and 37 /65 were non-neoplastic, according to the final diagnosis. In Stage II, 56/106 were neoplastic with a sensitivity, specificity, PPV, NPV, LR + , and LR - for neoplastic diagnosis of 96.3 %, 92.3 %, 92.9 %, 96 %, 12.52, and 0.04, respectively. The proposed classification presented high reproducibility among observers, for both neoplastic and subtypes categories. However, it was better for experts (κ > 80 %) than non-experts (κ 64.7 % - 81.9 %).

CONCLUSION

The novel classification system could help physicians to distinguish non-neoplastic from neoplastic bile duct lesions.

Cholangioscopy in the digital era

Cholangioscopy allows direct visualization and subsequent therapeutic maneuvers of the biliary ductal system. With advances in endoscopic and imaging technology, cholangioscopy has become an important modality for the diagnosis of indeterminate biliary strictures and an essential therapeutic tool for difficult to remove biliary stones. Enhanced imaging and operability of the latest generation cholangioscopes have further expanded their clinical applications to include ductal tumor ablation, gallbladder drainage, access to difficult to reach branches of the biliary tree, and biliary foreign body manipulation. In this review, we discuss the technical evolution of cholangioscopy into the digital era and review the clinical evidence supporting its use in the diagnosis and therapy of biliary tract disease.

Cholangioscopy Is Safe and Feasible in Elderly Patients

BACKGROUND & AIMS

Although cholangioscopy is widely used during endoscopic retrograde cholangiopancreatiography (ERCP), its safety and feasibility for elderly patients are not well established. We aimed to evaluate the safety and feasibility of cholangioscopy in elderly patients.

METHODS

We performed a retrospective study of all ERCPs with single-operator cholangioscopy (SOC) performed at 3 tertiary referral hospitals from March 2012 through October 2015. We collected data on patient demographics, procedure indications, findings, complications, and success rates (complete success was achieved if all intended diagnostic and therapeutic procedures were performed, such as tissue sample collection or complete removal of stones). The cohort was divided into 3 groups: patients younger than 65 years (group 1, n = 178), patients 65-75 years old (group 2, n = 86), and patients older than 75 years (group 3, n = 77). We used 1-way ANOVA, the χ² test, and the Wilcoxon sum rank test to compare study variables. The primary aim was to assess rates of complications from ERCP with SOC in elderly patients compared with younger patients.

RESULTS

Baseline clinical features were similar among groups, except for a higher prevalence of co-morbidities in group 3. The indication for and findings from ERCP with SOC differed among the groups; stricture or tumor was the most common indication in groups 1 and 3-the most common findings were strictures and masses, respectively. In group 2, choledocholithiasis was the most common indication and finding. The success rate, analyzed in a subset of 209 patients, was 88.5% overall and did not differ significantly among groups. The overall rate of complication was 7.33% with no significant difference among groups (7.30% for group 1, 6.98% for group 2, and 7.79% for group 3) (P < .17).

CONCLUSIONS

In a retrospective analysis of ERCPs with SOCs, we found this procedure to be safe for elderly patients (older than 75 years), who had rates of complications and hospital admission similar to those of younger patients.

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.

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.

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.

Outcomes of Different Methods for Analysis of Biliary Brush Cytology and of Factors Associated with Positive Diagnosis in an Age-Dependent Retrospective Review

Background and Aims

Brush cytology during endoscopic retrograde cholangiopancreatography (ERCP) is the most frequently used strategy for obtaining a tissue sample from an indeterminate biliary stricture. A recent study reported that age is a factor associated with positive yields, but further analysis of how age influences the results was lacking. We aimed to evaluate clinical effectiveness of biliary cytology and prognostic factors for a positive outcome, especially age.

Methods

This study was a single-center, retrospective, clinical study of 77 consecutive patients who underwent brush cytology during ERCP to obtain a diagnosis of an indeterminate biliary stricture. We compared 2 routine cytology techniques: A (smear); B (centrifugation of the cytological material collected and the cut-off brush + cell block when sufficient amount of material was available). The data were collected aiming to compare the accuracy of the different techniques used and the prognostic factors affecting the outcome, with a particular focus on age. The yield for brush cytology was compared with the gold standard defined as either definitive histology or the long-term clinical course.

Results

The overall accuracy of the 2 used methods was 75.3%. Sensitivity was 52.5%, specificity was 100%, positive predictive value was 100%, and negative predictive value was 66.1%. Although not statistically significant, there was a trend toward accuracy for method B compared with method A (80.4 vs. 65.4%; p = 0.153). Multiple logistic regression analysis showed that younger age was the only independent prognostic factor associated with a positive diagnosis (OR 0.95; 95% CI 0.90-0.99; p = 0.039). Receiver operating characteristic curves for age yielded an area under the curve value of 68.2%. On the basis of the Youden index, 69 years was found to be the optimal cutoff for age.

Conclusions

In this series, the accuracy of routine biliary brush cytology was not equal for all methods and ages; in particular, younger patients (below 69 years) tended to have a higher probability of a correct diagnosis.

Prospective evaluation of digital single-operator cholangioscope for diagnostic and therapeutic procedures (with videos)

BACKGROUND AND AIM

Recently, the digital single-operator cholangioscope (SPY-DS) has become available. This system may allow diagnosis by direct visualization and allow performance of various therapeutic procedures. The aim of the present study was to prospectively evaluate the clinical utility of DSOCS for diagnostic and therapeutic procedures for biliary disease.

METHODS

Technical success was defined as successful visualization of target lesions in the biliary tract and carrying out forceps biopsy as a diagnostic procedure, and successfully carrying out treatment such as guidewire insertion for the area of interest, electrohydraulic lithotripsy (EHL), or migrated stent removal. Also, the present study aimed at investigating diagnostic yield of the cholangioscopic findings and biopsy specimens.

RESULTS

A total of 55 consecutive patients were prospectively enrolled in this study; a diagnostic procedure was done in 33 patients, and a therapeutic procedure was done in 22 patients. Overall accuracy of visual findings was 93%, with a sensitivity of 83%, a specificity of 89%, positive predictive value (PPV) of 83%, and negative predictive value (NPV) of 100%. However, the overall accuracy of forceps biopsy was 89%, with a sensitivity, specificity, and PPV of 100%, and NPV of 90%. Overall technical success rate of therapeutic procedures such as selective guidewire insertion, EHL or migrated stent removal was 91% (20/22). Finally, adverse events were seen in two cases in the diagnostic group, but were not seen in the therapeutic group.

CONCLUSION

Although additional cases and a randomized, controlled study with another cholangioscope are needed, diagnostic and therapeutic procedures using SPY-DS appear to be feasible and safe.

A feasibility study of digital single-operator cholangioscopy for diagnostic and therapeutic procedure (with videos)

Recently, the novel SpyGlass DS Direct Visualization system (SPY DS) has become available. This system offers several advantages over the conventional SPYGlass system. This study evaluated the clinical feasibility and efficacy of diagnostic and therapeutic procedures for biliary disorder using SPY DS.In this retrospective study, consecutive patients who had biliary disorder were enrolled between November 2015 and February 2016. All patients could not be diagnosed or treated by standard endoscopic retrograde cholangiopancreatography in our hospital or at another hospital.A total of 28 consecutive patients (21 men and 7 women; median age, 73 years; age range, 55-87 years) were retrospectively enrolled in this study. Among them, diagnostic procedure was performed in 20 patients, and 8 patients underwent therapeutic procedures. The technical success rate for diagnostic procedures was 100% (20/20). Diagnostic accuracy was 100% (19/19). The technical success rate for therapeutic procedures was 88% (7/8). Among these 8 patients, 4 patients with common bile duct stones underwent electrohydraulic lithotripsy. One patient successfully underwent guidewire insertion to remove a migrated plastic stent. The 3 remaining patients underwent SPY DS to insert a guidewire for left bile duct obstruction and for posterior bile duct branch. In the patient who underwent guidewire insertion for left hepatic bile duct obstruction cause by primary sclerosing cholangitis, we could not advance the guidewire into the left hepatic bile duct. No adverse events were seen. Median SPY DS insertion time was 21 min (range, 8-32 min).Single-operator cholangioscopy using SPY DS was feasible and had a marked clinical impact in patients with biliary disease. Additional case reports and prospective studies are needed to examine further applications of this system.

Per-oral video cholangiopancreatoscopy with narrow-band imaging for the evaluation of indeterminate pancreaticobiliary disease

BACKGROUND AND AIMS

Cholangiopancreatoscopy for evaluating pancreaticobiliary pathology is currently limited by suboptimal optics. The aim of this study was to characterize the operating characteristics of per-oral video cholangiopancreatoscopy with narrow-band imaging (POVCP) findings in indeterminate pancreaticobiliary disease and to describe their association with neoplasia.

METHODS

Data from consecutive patients undergoing POVCP for the evaluation of indeterminate pancreaticobiliary disease at a single tertiary care center were analyzed. Two experienced investigators had previously agreed on POVCP findings and terminology that were documented in endoscopy reports. Endoscopic procedural data from POVCPs performed between January 2006 and April 2015 and clinical data were abstracted from the endoscopic database and electronic medical records. Study endpoints included tissue-proven neoplasia or benign disease with ≥1 year of follow-up.

RESULTS

A total of 109 patients were identified; 13 were excluded because of the presence of stone disease, known pancreaticobiliary malignancy, or presumed benign disease with ≤1 year of follow-up. Most patients (85%) underwent POVCP for biliary disease and 15% underwent POVCP for a pancreatic cause. Tortuous and dilated vessels (P < .001), infiltrative stricture (P < .001), polypoid mass (P = .003), and the presence of fish-egg lesions (P = .04) were found to be significantly associated with neoplasia. The overall POVCP impression had a high sensitivity (85%) and negative predictive value (89%) in assessing for the presence of neoplasia.

CONCLUSIONS

Per-oral video cholangiopancreatoscopy is effective in the evaluation of indeterminate pancreaticobiliary disease. Tortuous and dilated vessels, infiltrative stricture, polypoid mass, and the presence of fish-egg lesions are significantly associated with neoplasia.

Usefulness of the single-operator cholangioscopy system SpyGlass in biliary disease: a single-center prospective cohort study and aggregated review

BACKGROUND AND STUDY AIM

Indeterminate biliary strictures and difficult bile duct stones remain clinically arduous and challenging situations. We aimed to evaluate the utility of the single-operator cholangioscopy (SOC)-system SpyGlass in both conditions in a single-center biliopancreatic interventional unit and in perspective of available aggregated literature.

METHODS

Usefulness of SOC was assessed for the above-mentioned indications by means of the combination of successful procedural completion, clinical success and incidence of procedure-related adverse events in our own prospective cohort from 3/2010 to 7/2014 and all available literature till 6/2015.

RESULTS

Our single-center cohort constituted of 84 patients undergoing SpyGlass either for indeterminate strictures (n = 45) or difficult stones (n = 39). In addition, a comprehensive literature review yielded 851 patients (from 15 series) for either stenosis (n = 646, 75.9 %) and difficult stones (n = 205, 24.1 %). In our series, overall procedural success amounted to 85.7 % (with 88.9 % for stenosis or 82.1 % for stones) compared to 90.7, 91.5 and 88.3 % in overall literature, respectively. Sensitivity, specificity and accuracy for visual diagnosis in our cohort added up to 83.3, 82.9 and 82.9 % compared to 90.8, 90.9 and 90.8 % in the pooled analysis. Respective figures for SOC-directed biopsies totaled 85.7, 100 and 95.7 % in our cohort and 72.4, 100 and 84 % overall. Overall procedure-related complications varied between 9.4 and 21.4 %.

CONCLUSIONS

The SOC-platform SpyGlass can be considered useful in the context of indeterminate biliary strictures and difficult-to-remove biliary stones. In both, SpyGlass-assisted intervention is associated with high procedural success and alters clinical outcome compared to conventional approaches with an acceptable safety profile.

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.

The efficacy of peroral cholangioscopy for difficult bile duct stones and indeterminate strictures: a systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

Current evidence supporting the efficacy of peroral cholangioscopy (POC) in the evaluation and management of difficult bile duct stones and indeterminate strictures is limited. The aims of this systematic review and meta-analysis were to assess the following: the efficacy of POC for the therapy of difficult bile duct stones, the diagnostic accuracy of POC for the evaluation of indeterminate biliary strictures, and the overall adverse event rates for POC.

PATIENTS AND METHODS

Patients referred for the removal of difficult bile duct stones or the evaluation of indeterminate strictures via POC were included. Search terms pertaining to cholangioscopy were used, and articles were selected based on preset inclusion and exclusion criteria. Quality assessment of the studies was completed with a modified Newcastle-Ottawa Scale. After critical literature review, relevant outcomes of interest were analyzed. Meta-regression was performed to examine potential sources of between-study variation. Publication bias was assessed via funnel plots and Egger's test.

RESULTS

A total of 49 studies were included. The overall estimated stone clearance rate was 88 % (95 % confidence interval [95 %CI] 85 % - 91 %). The accuracy of POC was 89 % (95 %CI 84 % - 93 %) for making a visual diagnosis and and 79 % (95 %CI 74 % - 84 %) for making a histological diagnosis. The estimated overall adverse event rate was 7 % (95 %CI 6 % - 9 %).

CONCLUSIONS

POC is a safe and effective adjunctive tool with endoscopic retrograde cholangiopancreatography (ERCP) for the evaluation of bile duct strictures and the treatment of bile duct stones when conventional methods have failed. Prospective, controlled clinical trials are needed to further elucidate the precise role of POC during ERCP.

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.

Single-operator cholangioscopy and targeted biopsies in the diagnosis of indeterminate biliary strictures: a systematic review

BACKGROUND AND AIMS

Evaluation of indeterminate biliary strictures by brush cytology and intraductal biopsies is limited by low sensitivity. The utility of SpyGlass peroral cholangioscopy for diagnosis of malignant biliary strictures and cholangiocarcinoma (CCA), in particular, remains unclear. Our aim was to study the utility of SpyGlass peroral cholangioscopy and targeted biopsy for diagnosis of malignant biliary strictures and CCA.

METHODS

In this systematic review, PubMed and Embase databases were reviewed for studies published to October 2014. The main outcomes of interest were sensitivity, specificity, and diagnostic odds ratio (DOR) of SpyGlass cholangioscopy in the diagnosis of malignant biliary strictures.

RESULTS

The search yielded 10 studies involving 456 patients. The pooled sensitivity and specificity of cholangioscopy-guided biopsies in the diagnosis of malignant biliary strictures was 60.1% (95% confidence interval [CI], 54.9%-65.2%) and 98.0% (95% CI, 96.0%-99.0%), respectively. The pooled DOR to detect malignant biliary strictures was 66.4 (95% CI, 32.1-137.5). Four studies included patients who had previous negative imaging and brushings and/or intraductal biopsies. Among these 4 studies, the pooled sensitivity and specificity for diagnosis of malignant biliary strictures was 74.7% (95% CI, 63.3%-84.0%) and 93.3% (95% CI, 85.1%-97.8%), respectively. The pooled DOR was 46.0 (95% CI, 15.4-138.1). Only 1 study directly compared the yield of SpyBite biopsies with standard brushings and biopsies. SpyBite biopsies had a sensitivity of 76.5% compared with brushings (5.8%) and biopsies (29.4%). Six studies specifically reported the role of cholangioscopy with targeted biopsies in the diagnosis of CCA. The pooled sensitivity and specificity to detect CCA was 66.2% (95% CI, 59.7%-72.3%) and 97.0% (95% CI, 94.0%-99.0%), respectively. The pooled DOR to detect CCA was 79.7 (95% CI, 32.7-194.7).

CONCLUSIONS

Our study suggests that SpyGlass cholangioscopy with SpyBite biopsies has moderate sensitivity for the diagnosis of malignant biliary strictures.

Hepatobiliary Tumors: Update on Diagnosis and Management

Tumors of the liver and biliary tree, mainly hepatocellular carcinoma and cholangiocarcinoma, are the second leading cause of cancer related death worldwide and the sixth leading cause of cancer related death among men in developed countries. Recent developments in biomarkers and imaging modalities have enhanced early detection and accurate diagnosis of these highly fatal malignancies. These advances include serological testing, micro-ribonucleic acids, fluorescence in situ hybridization, contrast-enhanced ultrasound, and hepatobiliary-phase magnetic resonance imaging. In addition, there have been major developments in the surgical and nonsurgical management of these tumors, including expansion of the liver transplantation criteria, new locoregional treatments, and molecularly targeted therapies. In this article, we review various types of hepatobiliary tumors and discuss new developments in their diagnosis and management.

Is single-operator peroral cholangioscopy a useful tool for the diagnosis of indeterminate biliary lesion? A systematic review and meta-analysis

BACKGROUND

Differentiating between malignant and benign biliary lesions is critical in clinical practice but is difficult.

OBJECTIVE

To systematically evaluate the diagnostic performance of single-operator peroral cholangioscopy on indeterminate biliary lesions.

DESIGN

A systematic review and meta-analysis.

PATIENTS

Patients with indeterminate biliary lesions or equivocal ERCP findings.

MAIN OUTCOME MEASUREMENTS

The diagnostic performance of single-operator peroral cholangioscopy on indeterminate biliary lesions. The area under the summary receiver-operating characteristic curve was used as the main indicator for the overall diagnostic performance of single-operator peroral cholangioscopy visual impression (VI) and SpyBite biopsy (SB). The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were also synthesized.

RESULTS

A total of 8 studies met the inclusion criteria, involving 335 patients who had data on VI and 337 who had data on SB. The area under the curve values on the summary receiver-operating characteristic curve of single-operator peroral cholangioscopy VI and SB were 0.94 (95% confidence interval [CI], 0.92-0.96) and 0.93 (95% CI, 0.90-0.95) respectively. The combined sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were 90% (95% CI, 73%-97%), 87% (95% CI, 76%-94%), 7.1 (95% CI, 3.8-13.3), 0.12 (95% CI, 0.04-0.33) for VI and 69% (95% CI, 57%-79%), 98% (95% CI, 92%-99%), 30.1 (95% CI, 8.5-106.9), and 0.32 (95% CI, 0.23-0.44) for SB, respectively.

LIMITATIONS

Small number of included studies; comparison with ERCP could not be made.

CONCLUSION

Single-operator peroral cholangioscopy is a good tool for differentiating malignant and benign biliary lesions. VI is useful for detecting malignant lesion, whereas SB is better at confirming a malignant diagnosis, but VI is not perfect in excluding biliary cancer, nor is SB, and their negative results should be interpreted with caution.

Interobserver agreement for single operator choledochoscopy imaging: can we do better?

Background. The SpyGlass Direct Visualization System (Boston Scientific, Natick, MA) is routinely used during single operator choledochoscopy (SOC) to identify biliary lesions or strictures with a diagnostic accuracy up to 88%. The objective of this study was to determine the interobserver agreement (IOA) of modified scoring criteria for diagnosing biliary lesions/strictures. Methods. 27 SPY SOC video clips were reviewed and scored by 9 interventional endoscopists based on published criteria that included the presence and severity of surface structure, vasculature visualization, lesions, and findings. Results. Overall IOA was "slight" for all variables. The K statistics are as follows: surface (K = 0.12, SE = 0.02); vessels (K = 0.14, SE = 0.02); lesions (K = 0.11, SE = 0.02); findings (K = 0.08, SE = 0.03); and final diagnosis (K = 0.08, SE = 0.02). The IOA for "findings" and "final diagnosis" was also only "slight." The final diagnosis was malignant (11), benign (11), and indeterminate (5). Conclusion. IOA using the modified criteria of SOC images was slight to almost poor. The average accuracy was less than 50%. These findings reaffirm that imaging criteria for benign and malignant biliary pathology need to be formally established and validated.