INTRODUCTION: Cholecystectomy (CCY) is the gold standard treatment of acute cholecystitis (AC). Nonsurgical management of AC includes percutaneous transhepatic gallbladder drainage (PT-GBD) and endoscopic ultrasound-guided gallbladder drainage (EUS-GBD). This study aims to compare outcomes of patients who undergo CCY after having received EUS-GBD vs PT-GBD. METHODS: A multicenter international study was conducted in patients with AC who underwent EUS-GBD or PT-GBD, followed by an attempted CCY, between January 2018 and October 2021. Demographics, clinical characteristics, procedural details, postprocedure outcomes, and surgical details and outcomes were compared. RESULTS: One hundred thirty-nine patients were included: EUS-GBD in 46 patients (27% male, mean age 74 years) and PT-GBD in 93 patients (50% male, mean age 72 years). Surgical technical success was not significantly different between the 2 groups. In the EUS-GBD group, there was decreased operative time (84.2 vs 165.4 minutes, P < 0.00001), time to symptom resolution (4.2 vs 6.3 days, P = 0.005), and length of stay (5.4 vs 12.3 days, P = 0.001) compared with the PT-GBD group. There was no difference in the rate of conversion from laparoscopic to open CCY: 5 of 46 (11%) in the EUS-GBD arm and 18 of 93 (19%) in the PT-GBD group (P value 0.2324). DISCUSSION: Patients who received EUS-GBD had a significantly shorter interval between gallbladder drainage and CCY, shorter surgical procedure times, and shorter length of stay for the CCY compared with those who received PT-GBD. EUS-GBD should be considered an acceptable modality for gallbladder drainage and should not preclude patients from eventual CCY.

Surgical resection remains the gold standard for pancreatic cancer, high-risk pancreatic neuroendocrine tumors (PNETs) and pancreatic cystic neoplasms (PCNs). However, a majority of pancreatic cancers are unresectable at the time of diagnosis. In addition, surgical resection of pancreatic lesions can be associated with morbidity and mortality. A less-invasive alternative therapeutic intervention to avoid short term and long-term adverse events is desirable, as is a minimally-invasive palliative therapy for unresectable or recurrent pancreatic cancers. Endoscopic ultrasound guided radiofrequency ablation (EUS-RFA) allows for selective tissue ablation with minimal injury to the surrounding tissue. EUS-RFA of pancreatic tumors has shown high clinical and technical success with acceptable side effects in pancreatic lesions, lymph nodes, and the celiac plexus. This paper will review the pathophysiology, available technology, safety and efficacy, and future directions of EUS-RFA.

Endoscopic ultrasound-guided biliary drainage (EUS-BD) has become widely accepted over the past several years for complicated biliary drainage. When conventional endoscopic retrograde cholangiopancreatography (ERCP) is not successful or feasible due to a variety of constraints, an ultrasound-guided technique through intrahepatic and extrahepatic approaches allows adequate management of hepatobiliary obstruction. Other management alternatives include percutaneous transhepatic biliary drainages (PTBD) and complicated surgical approaches, both of which can be associated with increased morbidity and mortality. There are various technical approaches to allow successful biliary drainage which will be reviewed in this article.

Background: Endoscopic ultrasound (EUS)-guided gastroenterostomy (EUS-GE) is a minimally invasive therapy for patients with gastric outlet obstruction without the risks of surgical bypass and the limited long-term efficacy of enteral self-expanding metal stent placement. However, due to its novelty, there is a lack of significant data comparing long-term outcomes of patients with EUS-GE, based on the underlying disease. In this study, we compare outcomes of EUS-GE on benign versus malignant indications. Methods: Consecutive patients from 12 international, tertiary care centers who underwent EUS-GE over 3 years were extracted in a retrospective registry. Demographic characteristics, procedure-related information and follow-up data was collected. Primary outcome was the rate of adverse events associated with EUS-GE and the comparison of the rate of adverse events in benign versus malignant diseases. Secondary outcomes included technical and clinical success as well as hospitalization admission. Results: A total of 103 patients were included: 72 malignant and 31 benign. The characteristics of the patients undergoing EUS-GE is shown in Table 1. The mean age of the cohort was 68 years and 58 years for malignant and benign etiology. Gender distribution was 57% and 39% being females in malignant and benign etiology group, respectively. Clinical success, technical success, average procedure time, and hospital length of stay were similar in both groups. Patients with benign underlying etiology had significantly higher number of surgically altered midgut anatomy (P=0.0379). Conclusion: EUS-GE is equally efficient regardless of the underlying etiology (malignant vs. benign), and the adverse events both groups were comparable.

Background and study aims First-generation optical coherence tomography (OCT) has been shown to increase diagnostic sensitivity for malignant biliary and pancreatic-duct strictures. A newer OCT imaging system, NVision Volumetric Laser Endomicroscopy (VLE), allows for in vivo cross-sectional imaging of the ductal wall at the microstructure level during endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to identify and evaluate characteristics on OCT that are predictive of benign and malignant strictures. Patients and methods Consecutive patients from six centers who underwent OCT between September 2016 and September 2017 were included in a dedicated registry. OCT images were analyzed, and nine recurring characteristics were further assessed. Final diagnosis was based on histology and/or surgical pathology. Results 86 patients were included (49 % male, mean age 64.7). OCT was performed in the bile duct in 79 patients and the pancreatic duct in seven. Nine OCT characteristics were identified: dilated hypo-reflective structures (n = 7), onion-skin layering (n = 8), intact layering (n = 17), layering effacement (n = 25), scalloping (n = 20), thickened epithelium (n = 42), hyper-glandular mucosa (n = 13), prominent blood vessels (n = 6), and a hyper-reflective surface (n = 20). Presence of hyper-glandular mucosa, hyper-reflective surface and scalloping significantly increased the odds of malignancy diagnosis by 6 times more (P = 0.0203; 95 % CI 1.3 to 26.5), 4.7 times more (P = 0.0255; 95 % CI 1.2 to 18.0) and 7.9 times more (P = 0.0035; 95 % CI 1.97 to 31.8) respectively. Conclusion By providing in-vivo cross-sectional imaging of the pancreatic and biliary duct wall, OCT technology may improve sensitivity in diagnosing malignant strictures and provide standardizable criteria predictive of malignancy.

Background/Aims: Peroral endoscopic myotomy (POEM) has been increasingly used for achalasia in Latin America, where Chagas disease is prevalent, and this makes POEM more challenging. The aim of this study was to determine the learning curve for POEM in Latin America.Methods: Patients undergoing POEM in Latin America with a single operator were included from a prospective registry over 4 years. Non-linear regression and cumulative sum control chart (CUSUM) analyses were conducted for the learning curve.Results: A total of 125 patients were included (52% male; mean age, 59 years), of which 80 had type II achalasia (64%), and 38 had Chagas disease (30%). The average pre-procedure and post-procedure Eckardt scores were 6.79 and 1.87, respectively. Technical success was achieved in 93.5% of patients, and clinical success was achieved in 88.8%. Adverse events occurred in 27 patients (22%) and included bleeding (4 patients), pneumothorax (4 patients), mucosal perforation (13 patients), mediastinitis (2 patients), and leakage (4 patients). The CUSUM chart showed a median procedure time of 97 min (range, 45-196 min), which was achieved at the 61st procedure. Procedure duration progressively decreased, with the last 10 procedures under 50 min approaching a plateau (p-value <0.01).Conclusions: Mastering POEM in Latin America requires approximately 61 procedures for both POEM efficiency and to accomplish the procedure within 97 minutes.