Introduction

Large series from eastern expert centres have defined the rate of submucosal invasive cancer (SMIC) in LNPCP according to subtype along with associated clinicopathological features. Large western series are very limited and provide conflicting results leading some authors to suggest differences in invasive potential between eastern and western patients with LNPCP. Notable differences exist between studies in reported associations between incidence of SMI and clinicopathological features which can heavily influence recommendations for therapeutic strategy.

Aims & Methods

We aimed to define the true risk of SMIC by morphological subtype and clinicopathological features of LNPCP in a large cohort of patients with LNPCP referred to a tertiary centre. All patients with LNPCP referred for consideration of treatment by ER at a tertiary referral centre between January 2011 and December 2024 were included. Data collected included morphological subtype of LNPCP, size, location, sex and age. The incidence of SMIC by morphological subtype was determined and significant differences in SMIC by clinicopathological features were sought.

Results

1641 LNPCP were treated by endoscopic resection. Mean size was 48mm (median 40mm, range 20-210mm). 43% of lesions were located in the right colon, 20% in the left colon and 37% in the rectum. 45% were treated using ESD and 57% were resected en bloc. The incidence of SMIC by morphological subtype was: laterally spreading tumour granular nodular mixed type (LST G NM) 13.4%; LST granular homogenous (LST GH) 2.8%, Is 12.9%; LST non granular (LST NG) flat-elevated 17.3% and LST NG pseudodepressed type (LST NG PD) 51.6%. SMIC was similar across size groups: 20-30mm 9.8%; 31-40mm 12.3%; 41-60mm 11.4% and >60mm 12.2% (p=0.59). No association was found between SMIC and age (p=0.35) or sex (p=0.12). SMIC was associated with rectal or left colon location: right colon 5.7%; left colon 14.9% and rectum 15.3% (p<0.001). For right colon LNPCP, the incidence of SMIC in LST G NM was 7.0%, LST NG 14.3% and LST NG PD 50.0%.

Conclusion

These data, from one of the largest single institution western series, help define the risk of SMIC according to clinicopathological features of LNPCP. High rates of en bloc resection increase the validity of these results. The risk of SMIC is largely determined by morphological subtype and occurred with similar incidence in this series to large series from eastern centres, suggesting similar tumour biology. Contrary to findings from some studies, size of LNPCP, age or sex are of limited significance. Although right colon LNPCP have a lower overall risk of SMIC, certain morphological subtypes still signal a high risk of SMIC justifying en bloc resection.

Introduction

Endoscopic retrograde cholangiopancreatography (ERCP) with stent placement is the current standard for drainage of distal malignant biliary obstruction (MBO), but carries a significant risk of post-procedural pancreatitis.[1] EUS-guided choledochoduodenostomy (EUS-CDS) is increasingly used as a promising alternative, but comparative studies are still scarce.[2,3] While previous studies have mainly focused on stent patency, the current study aims to evaluate whether EUS-CDS is superior to ERCP in achieving a textbook outcome for the patients, indicating an optimal post-procedural course.

Aims & Methods

This single-center study included patients with distal MBO who underwent technically successful (1) EUS-CDS with a lumen apposing metal stent (LAMS) plus additional coaxial stent or (2) ERCP with fully covered self-expandable metal stent (FCSEMS) as part of the prospective SCORPION studies and SPHINX trial, respectively.[1,4] The primary endpoint was textbook outcome, defined as the absence of procedure- or stent-related adverse events (AEs), reinterventions, or hospital readmissions within 30 days of the procedure. Secondary endpoints included individual components of the primary outcome, mortality, time to initiation of treatment (e.g., systemic therapy or surgery), and textbook outcome at 90 days.

Results

A total of 144 patients were enrolled for EUS-CDS (n=49) or ERCP (n=95). Primary etiologies included pancreatic cancer (n=117, 81%) and distal cholangiocarcinoma (n=14, 10%). Coaxial stents used in the EUS-CDS group were FCSEMS (n=20) or double pigtail plastic stents (n=29). Textbook outcome was achieved in 44 patients (90%) in the EUS-CDS group and in 67 patients (71%) in the ERCP group at 30 days (RR 1.27, 95% CI 1.08-1.50). EUS-CDS led to fewer procedure- or stent-related AEs (RR 0.35, 95% CI 0.14-0.84) compared with ERCP, particularly post-procedure pancreatitis (0% vs. 23%). Other AEs, including perforation (2% vs. 0%), bleeding (0% vs. 0%), stent dysfunction with or without cholangitis (4% vs. 6%), and cholecystitis (4% vs. 3%) were similar between groups. Hospital readmission rate was lower in the EUS-CDS group (6% vs. 30%, RR 0.21, 95% CI 0.07-0.65), as was the length of hospital stay (mean 0.3 days [SD 1.3] vs. 1.8 days [SD 4.0], P=0.01). In-hospital mortality (8% vs. 5%), need for reinterventions (8% vs. 6%), and time to treatment initiation, either surgery or chemotherapy, did not differ (median 33 days [IQR 23-42] vs. 30 days [IQR 18-41]). At 90 days, textbook outcome was more often present in the EUS-CDS group when compared to ERCP however the difference was no longer significant (78% vs. 69%, RR 1.22, 95% CI 1.02-1.44).

Conclusion

EUS-CDS with LAMS and additional coaxial stent was superior to ERCP with FCSEMS in achieving textbook outcome at 30 days post-procedure. EUS-CDS resulted in less procedure- or stent-related AEs, particularly post-procedure pancreatitis, and consequently in fewer hospital readmissions and shorter hospital stay. Therefore, when expertise is available, EUS-CDS with coaxial stent placement could be considered as primary biliary drainage technique in patients with distal MBO.

References

1. Onnekink, A. M., Gorris, M., Bekkali, N. L., et al (2024). Endoscopic sphincterotomy to prevent post-ERCP pancreatitis after self-expandable metal stent placement for distal malignant biliary obstruction (SPHINX): a multicentre, randomised controlled trial. Gut, gutjnl-332695. https://doi.org/10.1136/gutjnl-2024-332695
2. Teoh, A. Y. B., Napoleon, B., Kunda, R et al (2023). EUS-Guided choledocho-duodenostomy using lumen apposing stent versus ERCP with covered metallic stents in patients with unresectable malignant distal biliary obstruction: a multicenter randomized controlled trial (DRA-MBO trial). Gastroenterology, 165(2), 473-482.e2. https://doi.org/10.1053/j.gastro.2023.04.016
3. Chen, Y., Sahai, A., Donatelli, G. et al (2023). Endoscopic Ultrasound-Guided Biliary Drainage of First Intent With a Lumen-Apposing Metal Stent vs Endoscopic Retrograde Cholangiopancreatography in Malignant Distal Biliary Obstruction: A Multicenter Randomized Controlled Study (ELEMENT Trial). Gastroenterology, 165(5), 1249-1261.e5. https://doi.org/10.1053/j.gastro.2023.07.024
4. Fritzsche, J. A., Fockens, P., Besselink, M. G. et al (2024). Optimizing EUS-guided choledochoduodenostomy with lumen-apposing metal stents for primary drainage of malignant distal biliary obstruction (SCORPION-IIp): a prospective pilot study. Gastrointestinal Endoscopy. https://doi.org/10.1016/j.gie.2024.10.012

Disclosure

Paul Fockens acted as a consultant for Cook Endoscopy and Olympus, outside the submitted work.
Roy L.J. van Wanrooij acted as a consultant for Boston Scientific. Jeanin E. van Hooft has received research support from Cook Medical and acted as lecturer for Cook Medical, Boston Scientific and Falk, and as consultant for Olympus. Rogier P. Voermans received a research grant and acted as consultant for Boston Scientific. All outside the submitted work. All other authors declare that they have no competing financial interests or personal relationships that could have appeared to influence the work reported in this abstract.

Introduction

Post-procedural pancreatitis (PPP) is the most common adverse event associated with endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic ultrasound-guided choledochoduodenostomy (EUS-CDS) using a lumen-apposing metal stent is emerging as a promising approach for managing malignant distal biliary obstruction (MDBO), offering the potential to lower the risk of PPP. We compared the outcomes of EUS-CDS with ERCP when used as the primary modality for biliary decompression.

Aims & Methods

This was a multicenter randomized controlled study, enrolling consecutive patients admitted for obstructive jaundice due to malignant distal biliary obstruction with dilated common bile duct (CBD>15mm). Patients were randomly allocated to receive EUS-CDS or ERCP for primary biliary drainage. This was a superiority trial with post-procedural acute pancreatitis (abdominal pain, elevation in pancreatic enzymes, and hospitalisation) as primary outcome. Other outcomes included technical success, clinical success, adverse events, 6-months stent patency rate, and overall survival. Analyses were performed according to intention-totreat principles.

Results

Between April 2021 and October 2023, 220 patients were enrolled in the study (EUS-CDS group: 111; ERCP group: 109). EUS-CDS group showed a lower risk for post-procedural acute pancreatitis (1.8% in EUS-CDS group vs 7.3% in ERCP group; RR: 0.25, 95%CI 0.07-0.88). Technical success was achieved in 94.6% in EUS-CDS group vs 78.9% ERCP group (p value: <0.001), in a mean procedural time of 13.5+11.6 minutes, and 24.7+14.9 minutes, respectively (p value: <0.001). No differences were found in other adverse events, clinical success, stent patency, or overall mortality

Conclusion

EUS-CDS is superior to ERCP in reducing post-procedural acute pancreatitis risk, without significantly affecting the overall risk of adverse events. Additionally EUS-CDS showed improved technical success, and comparable clinical efficacy. These results support the use of EUS-CDS as the potential preferred primary approach in patients with dilated CBD (NCT04099862).

Introduction

Preoperative biliary drainage (PBD) is commonly used in patients with malignant distal biliary obstruction (MDBO) to maintain performance status, prevent cholangitis and allow subsequent surgical or neoadjuvant treatment. Endoscopic retrograde cholangiopancreatography (ERCP) is the first-line approach, but in cases of failure, percutaneous transhepatic biliary drainage (PTBD) or endoscopic ultrasound-guided biliary drainage (EUS-BD) are considered. While EUS-BD has shown favourable outcomes compared to PTBD in the palliative setting, evidence comparing these modalities in the preoperative setting is limited.

Aims & Methods

The aim of this study was to compare the efficacy, safety, and surgical outcomes of PTBD and EUS-BD in patients with MDBO after failed ERCP. This retrospective multicenter study included patients who underwent PTBD or EUS-BD followed by pancreaticoduodenectomy (PD) for periampullary cancer at 15 referral centers in Japan between January 2012 and December 2021. Only patients who had failed or were not amenable to ERCP were included. The primary outcome was surgery-related adverse events (AEs), while secondary outcomes included drainage efficacy, recurrence patterns, disease-free survival (DFS), and overall survival (OS). Propensity score matching (PSM) was used to adjust for baseline differences.

Results

In total, 2350 patients received PBD before PD. Of the 79 patients in whom ERCP failed, 65 underwent PTBD and 14 underwent EUS-BD. After PSM, 13 matched pairs were analyzed. Technical and clinical success rates were comparable between groups. However, the EUS-BD group had a significantly higher internalization success rate (100% vs. 46%, P=0.005) and fewer drainage sessions required (median: 1 vs. 2, P=0.015). The EUS-BD group also had a significantly shorter hospital stay for drainage (11 vs. 17 days, P=0.042). Rates of drainage-related AEs tended to be lower in the EUS-BD group, although not statistically significant. Surgery-related outcomes, including operative time, intraoperative blood loss, R0 resection rate, postoperative hospital stay, and surgery-related AEs, were not significantly different between groups. No cases of needle tract seeding were observed. Median DFS and OS were comparable between groups (DFS: 14.2 vs. 16.8 months, P=0.22; OS: 17.9 vs. 27.9 months, P=0.167).

Conclusion

EUS-BD showed comparable surgical outcomes and long-term oncological efficacy to PTBD, while offering superior internalization success, fewer interventions, and a shorter preoperative hospital stay. These advantages make EUS-BD a favorable alternative to PTBD in the preoperative management of MDBO after failed ERCP, particularly in patients scheduled for neoadjuvant therapy.

Disclosure

Kitano M has received grants from Boston Scientific, Zeon Medical Inc., and Medicos Hirata Inc. Takenaka M, Shiomi H, Kitagawa K, Shintani S, Maruyama H, Sagami R, Ikeura T, Ogura T, Ishida Y, Mandai K, Sugimori S, Imamura Y, Masuda A, Ikezawa K,Shimizu A, Nakai A, Nagai M and Nakano R have no conflicts of interest or financial ties to disclose.

Introduction

Colorectal anastomotic dehiscence (CAD) is one of the most severe postoperative complications in colorectal surgery, significantly impacting patient morbidity and mortality. Current risk assessment methods rely on clinical and intraoperative factors, but no real-time predictive tool exists. This study aimed to develop an artificial intelligence model based on intraoperative recording of the anastomosis for CAD prediction.

Aims & Methods

A convolutional neural network (CNN) was trained using a dataset of annotated frames from colorectal surgery videos across three international high-volume centers: IPO Lisboa, Hospital das Clínicas de Ribeirão Preto, São Paulo, Brazil and Royal Liverpool University Hospital. The dataset included a total of 5,356 annotated frames from 25 patients, 2,007 frames classified as CAD-positive and 3,349 as CAD-negative. Four CNN architectures (EfficientNetB0, EfficientNetB7, ResNet50, and MobileNetV2) were tested. Performance was evaluated using sensitivity, specificity, accuracy, and area under the receiver operating characteristic (AUROC) curve. Heatmaps were generated to identify key regions influencing predictions.

Results

The best-performing model achieved an accuracy of 99.55%, AUROC of 99.60%, sensitivity of 99.21%, specificity of 100%, PPV of 100%, and NPV of 98.94%. The model reliably identified CAD-positive frames and provided visual explanations through heatmaps.

Conclusion

To our knowledge, this is the first AI model developed to predict CAD using intraoperative video analysis. Its accuracy suggests the potential to redefine surgical decision-making by providing real-time risk assessment. Further refinement with a larger dataset and diverse surgical techniques could enable intraoperative interventions to prevent CAD before it occurs, marking a paradigm shift in colorectal surgery.