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.).

Learning Curve for Endoscopic Submucosal Dissection With an Untutored, Prevalence-Based Approach in the United States.

BACKGROUND & AIMS: Endoscopic submucosal dissection (ESD) is widely used in Asia to resect early-stage gastrointestinal neoplasms, but use of ESD in Western countries is limited. We collected data on the learning curve for ESD at a high-volume referral center in the United States to guide development of training programs in the Americas and Europe. METHODS: We performed a retrospective analysis of consecutive ESDs performed by a single operator at a high-volume referral center in the United States from 2009 through 2017. ESD was performed in 540 lesions: 449 mucosal (10% esophageal, 13% gastric, 5% duodenal, 62% colonic, and 10% rectal) and 91 submucosal. We estimated case volumes required to achieve accepted proficiency benchmarks (>90% for en bloc resection and >80% for histologic margin-negative (R0) resection) and resection speeds >9cm2/hr. RESULTS: Pathology analysis of mucosal lesions identified 95 carcinomas, 346 premalignant lesions, and 8 others; the rate of en bloc resection increased from 76% in block 1 (50 cases) to a plateau of 98% after block 5 (250 cases). The rate of R0 resection improved from 45% in block 1 to >80% after block 5 (250 cases) and ∼95% after block 8 (400 cases). Based on cumulative sum analysis, approximately 170, 150, and 280 ESDs are required to consistently achieve a resection speed >9cm2/hr in esophagus, stomach, and colon, respectively. CONCLUSIONS: In an analysis of ESDs performed at a large referral center in the United States, we found that an untutored, prevalence-based approach allowed operators to achieve all proficiency benchmarks after ∼250 cases. Compared with Asia, ESD requires more time to learn in the West, where the untutored, prevalence-based approach requires resection of challenging lesions, such as colon lesions and previously manipulated lesions, in early stages of training.

Esophageal Stenting With Sutures: Time to Redefine Our Standards?

BACKGROUND AND STUDY AIMS: Migration is the most common complication of the fully covered metallic self-expanding esophageal stent (FCSEMS). Recent studies have demonstrated migration rates between 30% and 60%. The aim of this study was to determine the effect of fixation of the FCSEMS by endoscopic suturing on migration rate. PATIENT AND METHODS: Patients who underwent stent placement for esophageal strictures and leaks over the last year were captured and reviewed retrospectively. Group A, cases, were patients who underwent suture placement and group B, controls, were patients who had stents without sutures. Basic demographics, indications, and adverse events (AEs) were collected. Kaplan-Meier analysis and Cox regression modeling were conducted to determine estimates and predictors of stent migration in patients with and without suture placement. RESULTS: Thirty-seven patients (18 males, 48.65%), mean age 57.2 years (±16.3 y), were treated with esophageal FCSEMS. A total of 17 patients received sutures (group A) and 20 patients received stents without sutures (group B). Stent migration was noted in a total of 13 of the 37 patients (35%) [2 (11%) in group A and 11 (55%) in group B]. Using Kaplan-Meier analysis and log-rank analysis, fixation of the stent with suturing reduced the risk of migration (P=0.04). There were no AEs directly related to suture placement. CONCLUSIONS: Anchoring of the upper flare of the FCSEMS with endoscopic sutures is technically feasible and significantly reduces stent migration rate when compared with no suturing, and is a safe procedure with very low AEs rates.

Impact of Radiofrequency Ablation on Malignant Biliary Strictures: Results of a Collaborative Registry.

BACKGROUND: Radiofrequency ablation of malignant biliary strictures has been offered for the last 3 years, but only limited data have been published. AIM: To assess the safety, efficacy, and survival outcomes of patients receiving endoscopic radiofrequency ablation. METHODS: Between April 2010 and December 2013, 69 patients with unresectable neoplastic lesions and malignant biliary obstruction underwent 98 radiofrequency ablation sessions with stenting. RESULTS: A total of 69 patients (22 male, aged 66.1 ± 13.3) were included in the registry. The etiology of malignant biliary stricture included unresectable cholangiocarcinoma (n = 45), pancreatic cancer (n = 19), gallbladder cancer (n = 2), gastric cancer (n = 1), and liver metastasis from colon cancer (n = 3). Seventy-eight percentage of patients had prior chemotherapy. All strictures were stented post-radiofrequency ablation with either plastic stents or metal stents. The mean stricture length treated was 14.3 mm. There was a statistically significant improvement in stricture diameter post-ablation (p < 0.0001). The likelihood of stricture improvement was significantly greater in pancreatic cancer-associated strictures [RR 1.8 (95 % 1.03-5.38)]. Seven patients (10 %) had adverse events, not linked directly to radiofrequency ablation. Median survival was 11.46 months (6.2-25 months). CONCLUSION: Radiofrequency ablation is effective and safe in malignant biliary obstruction and seems to be associated with improved survival.

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.

Endoscopic Ultrasound-Guided Treatment beyond Drainage: Hemostasis, Anastomosis, and Others.

Since the introduction of endoscopic ultrasound (EUS) in the 1990s, it has evolved from a primarily diagnostic modality into an instrument that can be used in various therapeutic interventions. EUS-guided fine-needle injection was initially described for celiac plexus neurolysis. By using the fundamentals of this method, drainage techniques emerged for the biliary and pancreatic ducts, fluid collections, and abscesses. More recently, EUS has been used for ablative techniques and injection therapies for patients with for gastrointestinal malignancies. As the search for minimally invasive techniques continued, EUS-guided hemostasis methods have also been described. The technical advances in EUS-guided therapies may appear to be limitless; however, in many instances, these procedures have been described only in small case series. More data are required to determine the efficacy and safety of these techniques, and new accessories will be needed to facilitate their implementation into practice.