EUS-directed Transenteric ERCP (EDEE) in Patients With Benign and Malignant Underlying Conditions and Inaccessible Papilla/Biliodigestive Anastomosis (BDA)

Background and Study Objective Endoscopic retrograde cholangiopancreatography (ERCP) is considered the gold standard when biliary intervention is indicated. However, there are situations where conventional ERCP is no longer feasible - for example, in the presence of malignant gastric outlet obstruction.

Additionally, the number of patients with surgically altered anatomy due to benign or malignant underlying diseases is increasing. For this group of patients, enteroscopy-assisted ERCP can generally be considered. However, the success rate of this procedure varies depending on the anatomical situation and is only around 61.7%. Therefore, patients in whom the papilla or the biliodigestive anastomosis (BDA) cannot be reached either via conventional endoscopy or enteroscopy-assisted ERCP - yet require biliary intervention - present a particular clinical challenge.

Traditionally, the only option in such cases has often been percutaneous transhepatic drainage (PTBD). This approach frequently requires repeated procedures over several months and, in some cases, results in a permanent external drainage. In recent years, endoscopic ultrasound (EUS)-guided techniques have emerged as a promising treatment option for this patient population. These methods show a high technical success rate of approximately 90%, but are not suitable in cases requiring complex interventions (e.g., multiple strictures of the BDA) or when targeting the right biliary system.

An alternative approach involves a two-step procedure: first, an EUS-guided entero-enteric anastomosis is created using a lumen-apposing metal stent (LAMS); in a second step, ERCP is performed via the LAMS. This procedure is referred to in the literature as Endoscopic Ultrasound-Directed Transenteric ERCP (EDEE).

Since only a few systematic studies on this alternative procedure have been published so far, the objective of this retrospective study is to assess the technical and clinical success rates and evaluate the safety of EDEE.

• Clinical success rate [Time frame: at the day of last procedure]
• Technical aspects of gastro-enterostomy [Time frame: during the procedure]
• Techinical aspect of ERCP via LAMS [Time frame: during procedure]
• Requirement for reinterventions [Time frame: during the procedure]