Background: Endoscopic Ultrasound (EUS) is widely used for the diagnosis of bilio-pancreatic and gastrointestinal (GI) tract diseases, for the evaluation of subepithelial lesions, and for sampling of lymph nodes and solid masses located next to the GI tract. The role of Artificial Intelligence in healthcare in growing. This review aimed to provide an overview of the current state of AI in EUS from imaging to pathological diagnosis and training. Methods: AI algorithms can assist in lesion detection and characterization in EUS by analyzing EUS images and identifying suspicious areas that may require further clinical evaluation or biopsy sampling. Deep learning techniques, such as convolutional neural networks (CNNs), have shown great potential for tumor identification and subepithelial lesion (SEL) evaluation by extracting important features from EUS images and using them to classify or segment the images. Results: AI models with new features can increase the accuracy of diagnoses, provide faster diagnoses, identify subtle differences in disease presentation that may be missed by human eyes, and provide more information and insights into disease pathology. Conclusions: The integration of AI in EUS images and biopsies has the potential to improve the diagnostic accuracy, leading to better patient outcomes and to a reduction in repeated procedures in case of non-diagnostic biopsies.

Endoscopic retrograde cholangiopancreatography (ERCP) is considered the preferred method for managing biliary obstructions. However, the prevalence of surgically modified anatomies often poses challenges, making the standard side-viewing duodenoscope unable to reach the papilla in most cases. The increasing instances of surgically altered anatomies (SAAs) result from higher rates of bariatric procedures and surgical interventions for pancreatic malignancies. Conventional ERCP with a side-viewing endoscope remains effective when there is continuity between the stomach and duodenum. Nonetheless, percutaneous transhepatic biliary drainage (PTBD) or surgery has historically been used as an alternative for biliary drainage in malignant or benign conditions. The evolving landscape has seen various endoscopic approaches tailored to anatomical variations. Innovative methodologies such as cap-assisted forward-viewing endoscopy and enteroscopy have enabled the performance of ERCP. Despite their utilization, procedural complexities, prolonged durations, and accessibility challenges have emerged. As a result, there is a growing interest in novel enteroscopy and endoscopic ultrasound (EUS) techniques to ensure the overall success of endoscopic biliary drainage. Notably, EUS has revolutionized this domain, particularly through several techniques detailed in the review. The rendezvous approach has been pivotal in this field. The antegrade approach, involving biliary tree puncturing, allows for the validation and treatment of strictures in an antegrade fashion. The EUS-transmural approach involves connecting a tract of the biliary system with the GI tract lumen. Moreover, the EUS-directed transgastric ERCP (EDGE) procedure, combining EUS and ERCP, presents a promising solution after gastric bypass. These advancements hold promise for expanding the horizons of comprehensive and successful biliary drainage interventions, laying the groundwork for further advancements in endoscopic procedures.

There are different cancers in the peri-ampullary region, including pancreatic ductal adenocarcinoma (PDAC), duodenum cancers (DCs), and ampullary adenocarcinoma (AAC). Here, significant morphological–molecular characterizations should be necessary for the distinction of primary tumours and classifications of their subtypes of cancers. The sub classification of AACs might include up to five different variants, according to different points of view, concerning the prevalence of the two more-cellular components found in the ampulla. In particular, regarding the AACs, the most important subtypes are represented by the intestinal (INT) and the pancreato-biliary (PB) ones. The subtyping of AACs is essential for diagnosis, and their identifications have been impacting clinical management responses to treatments and overall survival (os) after surgery. Pb is associated with a worse clinical outcome. Otherwise, the criteria, through which are possible to attribute its subtype classification, are not well established. A triage of immune markers represented by CK7, CK20, and CDX-2 seem to represent the best compromise in order to split the cohort of AAC patients in the INT and PB groups. The test of choice for the sub-classification of AACs is represented by the immuno-histochemical approach, in which its molecular classification acquires its diagnostic, predictive, and prognostic value for both the INT and PB patients.

Endoscopic palliation of concomitant biliary and duodenal malignant obstruction can be challenging because of difficult access to the papilla, which may consequently result in possible failure of endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic ultrasonography-guided biliary drainage (EUS-BD), either before or after duodenal stent placement, has emerged as an alternative approach in these cases. A novel cautery-tipped lumen apposing metal stent (LAMS; Hot-AXIOS, Boston Scientific Corp., Natick, Massachusetts, USA) has recently been developed for this purpose [1] [2] [3]. In this case series, we describe a new approach for the palliation of patients presenting with simultaneous duodenal and biliary obstruction based on the single-session sequential deployment of this novel cautery-tipped LAMS and a duodenal stent in patients with unreachable papilla or failed ERCP. Four patients with unresectable pancreatic cancer (three men, one woman; mean age 63 ± 18) and one man aged 53 with a duodenal adenocarcinoma were treated. Biliary drainage was obtained by placing the LAMS by the transbulbar approach under EUS guidance in a fluoroless and wireless manner ([Fig. 1] and [Fig. 2 a]; [Video 1]). A duodenal self-expanding metal stent (SEMS; WallFlex Enteral, Boston Scientific) was placed, taking care to avoid overlapping the LAMS, during the same endoscopic session [4] ([Fig. 2 b] and [Fig. 3]; [Video 2]). The overall technical success rate for both EUS-guided choledochoduodenostomy and duodenal stenting was 100 %. The mean time for the whole procedure was 45 ± 5.7 minutes (range 38 – 52) and for the EUS-BD was 19 ± 0.8 minutes (range 18 – 20). No early or late complications were observed and the mean bilirubin level of the patients 1 week after stent placement had decreased from 14.5 mg/dL (range 11.8 – 18.3) to 2.9 mg/dL (range 2.1 – 4.9). Our report suggests that a single-session endoscopic sequential approach for palliation of concomitant biliary and duodenal obstruction using a cautery-tipped LAMS can be proposed as a safe and effective technique in patients with an unreachable papilla due to malignant duodenal obstruction. Endoscopy_UCTN_Code_TTT_1AR_2AZ