EUS-guided gallbladder drainage: Where will we go next?

Endoscopic Gallbladder Drainage: A Comprehensive Review on Indications, Techniques, and Future Perspectives

In recent years, therapeutic endoscopy has become a fundamental tool in the management of gallbladder diseases in light of its minimal invasiveness, high clinical efficacy, and good safety profile. Both endoscopic transpapillary gallbladder drainage (TGBD) and endoscopic ultrasound (EUS)-guided gallbladder drainage (EUS-GBD) provide effective internal drainage in patients with acute cholecystitis unfit for cholecystectomy, avoiding the drawbacks of external percutaneous gallbladder drainage (PGBD). The availability of dedicated lumen-apposing metal stents (LAMS) for EUS-guided transluminal interventions contributed to the expansion of endoscopic therapies for acute cholecystitis, making endoscopic gallbladder drainage easier, faster, and hence more widely available. Moreover, EUS-GBD with LAMS opened the possibility of several cholecystoscopy-guided interventions, such as gallstone lithotripsy and clearance. Finally, EUS-GBD has also been proposed as a rescue drainage modality in malignant biliary obstruction after failure of standard techniques, with encouraging results. In this review, we will describe the TBGD and EUS-GBD techniques, and we will discuss the available data on clinical efficacy in different settings in comparison with PGBD. Finally, we will comment on the future perspectives of EUS-GBD, discussing the areas of uncertainty in which new data are more strongly awaited.

Endoscopic ultrasound in the management of acute cholecystitis: Practical review

Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) has emerged over the last years as an alternative procedure to percutaneous drainage (PT)-GBD in patients with acute cholecystitis (AC) at high surgical risk. This process has been driven by the advent of lumen-apposing metal stents (LAMS) with electrocautery-enhanced capability, which has rendered the drainage procedure easier to accomplish and safer. Studies and meta-analyses have proven the superiority of EUS-GBD over PT-GBD in high-surgical-risk patients with AC. Little evidence exists in the same setting that EUS-GBD compares equally with laparoscopic cholecystectomy (LC). Moreover, EUS-GBD might theoretically have a possible role in patients at high surgical risk with an indication to undergo cholecystectomy or with a high probability of conversion from LC to open cholecystectomy. Properly designed studies are needed to better clarify the role of EUS-GBD in these patient populations.

Endoscopic Ultrasound-Guided Locoregional Treatments for Solid Pancreatic Neoplasms

Solid pancreatic neoplasms are one of the most diagnosed gastrointestinal malignancies thanks to the current and progressive advances in radiologic methods. Endoscopic ultrasound-guided techniques have over time gained a prominent role in the differential diagnosis and characterization of these pancreatic lesions, including pancreatic cancer, neuroendocrine tumors, and metastases. Recently, several endoscopic ultrasound-guided locoregional treatment techniques, which are divided into thermal ablative techniques and non-thermal injection techniques, have been developed and applied in different settings for the treatment of solid pancreatic neoplasms. The most common ablative techniques are radiofrequency, microwave, laser, photodynamic therapy and hybrid techniques such as hybrid cryothermal ablation. The most common injection techniques are ethanol injection, immunotherapy and brachytherapy. In this review, we update evidence about the efficacy and safety of endoscopic ultrasound-guided locoregional treatments for solid pancreatic neoplasms.

Current landscape of therapeutic EUS: Changing paradigms in gastroenterology practice

Therapeutic EUS has witnessed exponential growth in the last decade, but it has been considered investigational until recently. An increasing body of good-quality evidence is now demonstrating clear advantages over established alternatives, adding therapeutic EUS to management algorithms of complex hepato-pancreato-biliary (HPB) and gastrointestinal (GI) conditions. In this review, the available evidence and clinical role of therapeutic EUS in established and evolving applications will be discussed. A Graphical Summary for each scenario will provide (1) technical steps, (2) anatomical sketch, (3) best-supporting evidence, and (4) role in changing current and future GI practice. Therapeutic EUS has accepted well-established applications such as drainage of symptomatic peripancreatic fluid collections, biliary drainage in failed endoscopic retrograde cholangiopancreatography, and treatment of acute cholecystitis in unfit-for-surgery patients. In addition, good-quality evidence on several emerging indications (e.g., treatment of gastric outlet obstruction, local ablation of pancreatic solid lesions, etc.) is promising. Specific emphasis will be given to how these technical innovations have changed management paradigms and algorithms and expanded the possibilities of gastroenterologists to provide therapeutic solutions to old and emerging clinical needs. Therapeutic EUS is cementing its role in everyday practice, radically changing the treatment of different HPB diseases and other conditions (e.g., GI obstruction). The development of dedicated accessories and increased training opportunities will expand the ability of gastroenterologists to deliver highly effective yet minimally invasive therapies, potentially translating into a better quality of life, especially for oncological and fragile patients.

Feasibility of therapeutic endoscopic ultrasound in the bridge-to-surgery scenario: The example of pancreatic adenocarcinoma

Upfront resection is becoming a rarer indication for pancreatic ductal adenocarcinoma, as biologic behavior and natural history of the disease has boosted indications for neoadjuvant treatments. Jaundice, gastric outlet obstruction and acute cholecystitis can frequently complicate this window of opportunity, resulting in potentially deleterious chemotherapy discontinuation, whose resumption relies on effective, prompt and long-lasting management of these complications. Although therapeutic endoscopic ultrasound (t-EUS) can potentially offer some advantages over comparators, its use in potentially resectable patients is primal and has unfairly been restricted for fear of potential technical difficulties during subsequent surgery. This is a narrative review of available evidence regarding EUS-guided choledochoduodenostomy, gastrojejunostomy and gallbladder drainage in the bridge-to-surgery scenario. Proof-of-concept evidence suggests no influence of t-EUS procedures on outcomes of eventual subsequent surgery. Moreover, the very high efficacy-invasiveness ratio over comparators in managing pancreatic cancer-related symptoms or complications can provide a powerful weapon against chemotherapy discontinuation, potentially resulting in higher subsequent resectability. Available evidence is discussed in this short paper, together with technical notes that might be useful for endoscopists and surgeons operating in this scenario. No published evidence supports restricting t-EUS in potential surgical candidates, especially in the setting of pancreatic cancer patients undergoing neoadjuvant chemotherapy. Bridge-to-surgery t-EUS deserves further prospective evaluation.

Trial sequential analysis of EUS-guided gallbladder drainage versus percutaneous cholecystostomy in patients with acute cholecystitis

BACKGROUND AND AIMS

Meta-analytic comparison of EUS-guided gallbladder drainage (EUS-GBD) versus percutaneous gallbladder drainage (PT-GBD) for acute cholecystitis (AC) brings the risk of spurious results if too few studies are included. Trial sequential analysis (TSA) can overcome this, providing information about its credibility.

METHODS

Comparative studies between EUS-GBD, using lumen-apposing metal stents, and PT-GBD for AC until July 2021 were used for conventional meta-analysis and TSA, which allowed the use of monitoring boundaries and the estimation of the required information size (RIS) needed to prove credibility.

RESULTS

Four studies accrued 535 patients. Technical success was in favor of PT-GBD (relative risk [RR], .967; P = .036), but TSA estimated that 1663 participants would be needed to avoid a Type I error (false positive). Clinical success was similar (RR, .965; P = .146), and TSA supported the absence of any demonstrable superiority of one therapy rather than a Type II error (false negative). EUS-GBD reduced overall adverse events (RR, .424; P < .001) and unplanned readmissions (RR, .215; P < .001), and TSA confirmed the avoidance of a Type I error, with early RIS achievement, providing necessary credibility. EUS-GBD had fewer reinterventions (RR, .244; P < .001), but a Type I error was not avoided, needing additional 97 patients to the accrued 535 to prove credibility.

CONCLUSIONS

PT-GBD can provide superior technical success than EUS-GBD if a very large sample size is accrued, thus limiting the single-patient benefit. Clinical success is probably equivalent. EUS-GBD convincingly decreased overall adverse events and unplanned readmissions, whereas the need for reinterventions requires additional studies.