bluuebunny/crossref_metadata_2025_split huggingface dataset:
A134 ENDOSCOPIC RESECTION IS EFFECTIVE FOR COMPLEX LARGE NON-PEDUNCULATED COLORECTAL POLYPS
Authors: Jiang S X , Zarrin A , Walia A , Galorport C , Xiong W , Enns R , Lam E , Shahidi N 
Published: February 2024

Abstract

Background
Endoscopic resection is preferred for most large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs) due to superior efficacy, safety, and cost-efficiency compared to surgery. However, endoscopic resection can be challenging due to anatomical location, lesion characteristics, and concomitant colonic disease; these complex LNPCPs (C-LNPCPs) historically have suboptimal outcomes compared to uncomplicated LNPCPs (UC-LNPCPs).

Aims
To compare the outcomes of C-LNPCPs to UC-LNPCPs following endoscopic resection.

Methods
Consecutive patients ampersand:003E 18 years of age who underwent endoscopic resection of a LNPCP were enrolled in a prospective single center observation cohort study (clinicaltrials.gov ID: NCT05402696). C-LNPCP were defined by at least one of the following criteria: involvement of the appendiceal orifice, ileocecal valve, or anorectal junction; previous resection attempt; ≥ 90% circumferential involvement; concomitant inflammatory bowel disease. All other lesions were classified as UC-LNPCPs. Performance was evaluated by technical success (all neoplastic tissue removed at index procedure), procedure-related adverse events (intra-procedural perforation, clinically significant post-endoscopic resection bleeding (CSPEB), delayed perforation, serositis), referral to surgery, and recurrence at first surveillance colonoscopy (SC1).

Results
From 06/2022-09/2023, 350 LNPCPs were referred for endoscopic resection and 335 were attempted (91 C-LNPCPs, 244 UC-LNPCPs). Median age was 68 years (IQR 62-74 years) and 144 (54.1%) were male. Median size was 30mm (IQR 20-40mm). Most lesions were adenomatous (63.7% C-LNPCPs, 64.8% UC-LNPCPs), with cancer identified in 3.3% and 4.9% of C-LNPCPs and UC-LNPCPs, respectively. EMR was the most common resection modality (62.6% C-LNPCPs vs. 64.8% UC-LNPCPs) with C-LNPCPs undergoing more ESD (17.6% vs. 7.0%) and less CSR (19.8% vs. 28.3%; p=0.011). Auxiliary modalities were more frequently used in C-LNPCPs (6.6% vs. 1.2% UC-LNPCPs; p=0.004). Technical success was 95.6% in C-LNPCPs compared to 99.2% in UC-LNPCPs (p=0.049). There was no significant difference between groups in the frequencies of adverse events. 17 LNPCPs (5.1%; 4 C-LNPCP, 13 UC-LNPCPs) underwent surgery (p=1.000). Of those LNPCPs assessed at SC1, there was 1 recurrence (1.0%) in the UC-LNPCP subgroup.

Conclusions
With site-specific technical modifications and mitigating strategies for procedural-related adverse events, endoscopic resection outcomes for C-LNPCPs are comparable to UC-LNPCPs.

Funding Agencies
None
A135 DEEPLY EMBEDDED ESOPHAGEAL FISHBONE REMOVED BY ENDOSCOPIC MUCOSAL DISSECTION: CASE REPORT AND LITERATURE REVIEW
Authors: Jugnundan S , Gupta S , Teshima C 
Published: February 2024

Abstract

Background
Foreign body ingestion is frequently encountered in gastroenterology clinical practice. While most objects pass spontaneously, sharp objects, most commonly bony fragments in adults, have a tendency to become lodged in the esophagus. The European and American Society of Gastrointestinal Endoscopy both recommend emergent endoscopy for sharp objects or bones impacted in the esophagus. However, there is little guidance regarding management of deeply embedded foreign bodies, that may not be visible intra-luminally or that may have penetrated the submucosa or muscularis propria.

Aims
In this case report, we describe successful endoscopic retrieval of a deeply embedded fishbone in the distal esophagus. A literature review was also conducted to evaluate the current evidence surrounding the use of endoscopic ultrasound (EUS) and submucosal dissection (ESD) to localize and remove deeply embedded foreign bodies.

Methods
A literature search on EUS and ESD use in foreign body retrieval was performed via MEDLINE/PubMed (September 2023) using relevant keywords and MeSH terms.

Results
CASE DESCRIPTION
A 50-year-old man presented to hospital with several hours of dysphagia after consuming fish. A fishbone deeply embedded through the submucosa into the muscularis propria was identified on CT scan and EUS. ESD was employed to free the bone and a fully covered metal stent was deployed to close the defect. The patient had no immediate complications and recovered well post-procedure.
Our literature search revealed a total of 6 case reports detailing endoscopic management of penetrating foreign bodies. One case used EUS to localize an object which was subsequently removed surgically. The remaining 5 cases all used ESD to remove submucosal objects without any short or long-term complications.

Conclusions
Clinical history is critical to prompt diagnosis of foreign body ingestion, and it is crucial to be familiar with the radiologic characteristics of the suspected object. Fishbones are frequently encountered and are most commonly radiolucent on plain films. CT scans should be obtained in these patients. Rarely, these objects will be found to be deeply penetrating. There are emerging case reports supporting the use of EUS in the localization of some of these objects, particularly when they cannot be seen intraluminally. Upon review of the literature, there is a paucity of reports describing their removal. This case report adds to the sparse literature demonstrating that ESD has an emerging role in the management of deeply penetrating foreign bodies. Following multidisciplinary discussion and consultation with the appropriate surgical service, ESD may prevent the need for otherwise invasive and potentially morbid surgical intervention.

Fishbone embedded in the distal esophagus. Removed by ESD, defect closed with metal stent.

Funding Agencies
None
A136 EXPLORING ENDOSCOPIST PERCEPTIONS OF ARTIFICIAL INTELLIGENCE-AIDED COLONOSCOPY: A QUALITATIVE ANALYSIS
Authors: Lee C , Parker C H , Liu L W , Salim M , Jeyalingam T 
Published: February 2024

Abstract

Background
Artificial intelligence (AI) is gaining recognition as a promising adjunct in healthcare including gastrointestinal endoscopy. Randomized controlled trials have demonstrated improved polyp detection with computer-aided detection (CADe) systems in colonoscopy. Despite the foreseeable translation of CADe systems into the endoscopy suite, no study to date has explored how introducing this novel technology influences endoscopist perceptions and cognitive processes.

Aims
To explore how AI assistance impacts endoscopists’ perceptions of and cognitive processes during colonoscopy.

Methods
Faculty in gastroenterology and general surgery at the University Health Network (Toronto, Canada) were interviewed in April 2023 to explore their baseline perceptions of AI before the planned installation of the Medtronic GI GeniusTM Intelligent Endoscopy Module, an AI polyp detection tool, at Toronto Western Hospital in May 2023. After performing a minimum of 10 colonoscopies using GI GeniusTM, participants were re-interviewed to discuss their perceptions of AI-assisted colonoscopy and how it influenced their cognition during the procedure. Analysis was informed by constructivist grounded theory, whereby interview data were transcribed and coded iteratively using constant comparison to generate themes.

Results
In this interim constant comparative analysis, 9 participants (6 gastroenterologists and 3 general surgeons) were interviewed to generate 16 interview transcripts (9 pre-exposure and 7 post-exposure; 1 interview pending, 1 participant on leave). Participants held the view that: (1) AI will inevitably become the standard of care in colonoscopy, where clinicians and AI function symbiotically and in partnership; (2) CADe systems may facilitate standardization of practice and reduce inter-endoscopist variability by improving detection of specific types of lesions (e.g., sessile serrated polyps); (3) CADe assistance provides a “second set of eyes” that interacts with, but does not replace, endoscopists’ cognitive processes; and (4) trainees should gain familiarity with AI systems, despite mixed opinions regarding AI’s specific role in training.

Conclusions
We found that study participants conceptualize AI as an essential component of colonoscopy practice and training, with endoscopist thought processes and CADe systems appearing to function symbiotically. Elucidating the specific ways in which AI and endoscopist cognition interact will facilitate the future refinement of these tools.

Funding Agencies
None
A138 ENDOSCOPIC SUBMUCOSAL DISSECTION OUTCOMES IN T1B COLORECTAL CANCER: A SINGLE CENTER EXPERIENCE
Authors: Milne F , Bechara R 
Published: February 2024

Abstract

Background
Endoscopic submucosal dissection (ESD) has transformed the approach to gastrointestinal neoplasms, particularly in managing T1 colorectal cancer(CRC) with superficial submucosal invasion (SMI), which is considered curative when other high-risk features are absent.

Aims
The aim of this study is to describe a single center’s experience with safety, and technical and clinical outcomes for patients undergoing ESD with T1b CRC, as well as explore differences in outcomes depending on depth of SMI.

Methods
This is a retrospective, single center study of patients who underwent ESD for suspected CRC at the Kingston Health Sciences Center, Ontario, Canada between October 2016 and April 2023. Patients with T1b CRC on their final pathology were included. We analyzed patient demographics, tumor characteristics, and technical outcomes. Patients were followed to determine cancer-free survival and tumor recurrence. Patients were stratified and compared by depth of SMI on their final pathology.

Results
A total of 32 patients with 33 T1b CRCs were included. 19 lesions had superficial SMI, and 14 had deep SMI on final specimens. Two procedures were aborted due to suspected deep invasion or fibrosis limiting ESD. The mean procedure time was 74.5 minutes and the mean efficiency was 12.3 min/cm3. ESD had high en-bloc (90.9%) and R0 (78.7%) resection rates, and there was no significant difference regardless of depth of SMI (p=0.08 and 0.372, respectively). 24 of 33 lesions had biopsy prior to ESD, and 22 of 24 lesions with previous histology (91.7%) had upgrade in pathology on their final ESD specimen. 2 patients had adverse events, and both were managed supportively.
A total of 9 patients (27%) went on to have surgery. Those with deep SMI were more likely to have surgery (5% vs 57%, pampersand:003C0.005). The most common reason was lymphovascular invasion (44%). However, in the 7 patients who had complete ESD procedure and subsequent surgery, none had residual cancer on their surgical specimens, or malignant lymph nodes.
The follow-up period for all patients ranged from 1 to 43 months with a mean follow-up time of 14.9 months. Of those who did not have surgery, all were cancer free at a mean follow up time of 16.2 months. Within the group of patients who had surgery, all were cancer free at a mean follow up time of 11.6 months. 5 patients died during the follow up period. None were from procedural related complications or disease recurrence.

Conclusions
ESD for T1b CRC is safe with high en-bloc and R0 resection rates. Patients with deep SMI were more likely to go on to have surgery, though this was frequently due to an additional high risk feature. Recurrence rates were low, but studies with longer follow up are needed.

Funding Agencies
None
A139 EARLY VIDEO CAPSULE ENDOSCOPY VERSUS COLONOSCOPY FOLLOWING NEGATIVE ESOPHAGOGASTRODUDENOSCOPY IN PATIENTS WITH SUSPECTED UPPER GASTROINTESTINAL BLEEDING: PRELIMINARY DATA FROM A RANDOMIZED CONTROLLED TRIAL
Authors: Patel K , Yang D , Krahn T , Wesilenko S , Halloran B , Zepeda-Gomez S 
Published: February 2024

Abstract

Background
Esophagogastroduodenoscopy (EGD) is recommended for initial endoscopic evaluation of patients with suspected upper gastrointestinal bleeding (UGIB). When this is negative, the standard recommendation is to perform a colonoscopy, despite low diagnostic yield of less than 5%. In these patients, the question remains as to whether small bowel investigations would be of higher yield prior to colonoscopy.

Aims
To compare the diagnostic yield between early video capsule endoscopy (VCE) versus colonoscopy after a negative EGD in patients with suspected UGIB.

Methods
This is preliminary data from a prospective randomized control trial (RCT) of adult patients with suspected UGIB (melena and hemoglobin drop of more than 20 g/L within 48 hours of admission). Patients at a single centre were enrolled prior to initial EGD; those with negative EGD were included and randomized to either colonoscopy (next day) or early VCE (immediately after EGD). Patients with a confirmed source of bleeding in their group required no further testing, but those without underwent further testing with the alternative (VCE or colonoscopy). We evaluated patient outcomes, including bleeding localization time, hospitalization duration, procedure count, complications and rebleeding rates.

Results
A total of 19 adult patients have been enrolled, of which 12 had negative EGD and were randomized to either VCE or colonoscopy, with six patients in each arm (Figure 1). In the VCE group, 100% (6/6) of patients had bleeding sources detected by early VCE, with 50% (3/6) of them undergoing endoscopic treatment. In the colonoscopy group, only one patient had a positive finding (1/6), the rest underwent subsequent VCE. The VCE identified the bleeding source in 80% (4/5) of patients with negative colonoscopy. Patient are outlined in Table 1.

Conclusions
Based on our preliminary data, the diagnostic yield of early and subsequent VCE was higher when compared to colonoscopy after initial negative EGD in patients with suspected UGIB.
Table 1. Summary of findings and patient outcomes

Funding Agencies
Medtronic Canada (Brampton, ON, CA) will provide the video capsule in the treatment group. This is the only equipment funding required in this study.
A141 RISK OF TOTAL METACHRONOUS ADVANCED NEOPLASIA AFTER DETECTION OF PROXIMAL HYPERPLASTIC POLYPS, ADENOMAS, AND THEIR COMBINATION
Authors: Safih W , von Renteln D , Popescu Crainic I , Haumesser C , Noyon B , Mubaid F , Rekkabi C , Marques P , Li Y , Djinbachian R 
Published: February 2024

Abstract

Background
Recent research findings have identified an association between proximal sessile serrated lesions (SSL) and a greater risk of advanced metachronous neoplasia, without significant impact of distal SSL.

Aims
The principal aim of this study was to assess the risk of total metachronous advanced neoplasia (T-MAN) at the follow-up (fu) colonoscopy after detection of proximal hyperplastic polyps (HP), adenomas and their combination at the initial colonoscopy.

Methods
Medical records for patients aged 45 to 74 who underwent colonoscopies in both 2014 and 2015 were reviewed. The primary outcome was the presence of T-MAN (comprising advanced adenomas or high-risk SL) during the follow-up colonoscopy depending on the presence of proximal HP, adenoma, or their combination at index colonoscopy. Secondary outcomes included assessing the risk of T-MAN at follow-up depending on index findings characteristics.

Results
2014 patients were screened and 764 were included in the final analysis (44.1% male vs 55.9% female; mean age, 63y; median follow-up, 3.46 years). Patients with both proximal hyperplastic polyps and colonic adenomas during their initial colonoscopy had a significantly higher risk of developing T-MAN than patients with a combination of adenomas and distal HP or with only adenomas at index colonoscopy (30.5% vs 19%) [Hazard-ratio (HR)=1.95 (95% confidence interval (CI)1.3-2.9)]. A combination of proximal hyperplastic polyps and colonic adenomas is associated with a higher risk of T-MAN during follow-up than proximal HP alone (30.5% vs 13.9%) [HR=3.4 (95% CI 1.3-8.7)]. No statistically significant evidence was found to identify an increased risk of developing T-MAN at follow-up in patients presenting adenomas alone vs those with only proximal HP (19.1% vs 13.9%) [HR=1.9 (95% CI 0.75-4.7)].

Conclusions
Patients with proximal hyperplastic polyps have an increased risk of presenting a T-MAN at the follow-up colonoscopy. Presenting a combination of hyperplastic polyps and adenomas indicates a higher risk of developing T-MAN than presenting an HP or adenoma alone.

Funding Agencies
Daniel von Renteln is supported by a "Fonds de Recherche du Québec Santé" career development award. He has also received research funding from ERBE Elektromedizin GmbH, Ventage, Pendopharm, Fujifilm and Pentax, and has received consultant or speaker fees from Boston Scientific Inc., ERBE Elektromedizin GmbH, and Pendopharm. Roupen Djinbachian is supported by a “Fonds de Recherche du Québec Santé/Ministère de la Santé et des Services Sociaux” clinical research award. The remaining authors declare that they have no conflict of interest.
A142 PROGNOSTICATING FACTORS AND OUTCOMES OF EARLY ENDOSCOPIC EVALUATION IN ACUTE UPPER GASTROINTESTINAL BLEEDING
Authors: Saunders M , Melchiorre H , Schmanda L , Savage D , Zezos P 
Published: February 2024

Abstract

Background
Current guidelines recommend esophagogastroduodenal endoscopy (EGD) early (ampersand:003C24 hours after presentation) for all suspected acute upper gastrointestinal bleeds (AUGIB). Among referral centers providing advanced tiers of care to large regions, treatment is often delayed secondary to geographic constraints. Metropolitan centers meet early EGD recommendations in up to 87.5% of patients. Some centers limit endoscopy to the ICU setting outside of normal hospital operational times. There is currently no data assessing Canadian referral center endoscopic timing, including factors delaying AUGIB endoscopy and outcomes.

Aims
The aim of this study was to report the prevalence of early EGD in AUGIB at a Northern Ontario referral center. Factors associated with delayed EGD and poor outcomes associated with AUGIB were also evaluated.

Methods
Of 441 patients retrospectively identified with an ICD-10 discharge diagnosis of gastrointestinal hemorrhage from 2016–22, 327 patients met inclusion criteria. Patients were excluded if they were below the age of 18 years at the time of presentation, had chronic UGIB, or lower gastrointestinal hemorrhage.

Results
Pre-endoscopic risk stratification via GBS and clinical Rockall score was high at 10 and 3, respectively. There were 279 patients who received early EGD for AUGIB, of which 56% were male. The median (IQR) time to endoscopy was 27.4 (29.3) hours with early EGD achieved in 46% of presentations. A significantly greater proportion of patients presenting to hospital on the weekend (n=105) had delayed EGD (pampersand:003C0.0001; Phi effect size 0.45). Patients presenting at times when EGD was unavailable (n=157) also experienced delayed EGD (pampersand:003C0.05). regional patients did not experience a greater proportion of delayed EGD. In multivariate analysis, presentation on the weekend, higher CCI, absence of pre-existing evidence of liver cirrhosis, and absence of major stigmata of recent hemorrhage on EGD were independent predictors of delayed EGD (Nagelkerke R2 = 0.379, pampersand:003C0.0001). The odds ratio for receiving late EGD was 8.9 times greater (95% CI 3.7–21.3) for patients presenting on the weekend (pampersand:003C0.0001). Longer endoscopy wait time was significant correlated with higher pre-EGD blood transfusions and longer length of stay (pampersand:003C0.001). Delayed EGD did not increase all-cause 30-day mortality.

Conclusions
Prevalence of delayed EGD in AUGIB was markedly elevated and associated with hospital presentation during times of limited endoscopic capabilities. Outcomes of delayed GED included increased length of stay and higher blood transfusion rates.

Funding Agencies
NOAMA
A144 ZENKER’S PERORAL ENDOSCOPIC MYOTOMY (Z-POEM) OUTCOMES IN TREATMENT OF ZENKER’S DIVERTICULUM: A RETROSPECTIVE CASE SERIES
Authors: Youssef M , Ching Hui Yee C , Bechara R 
Published: February 2024

Abstract

Background
Zenker’s diverticulum (ZD) is an outpouching of tissue in an area of the posterior hypopharynx called the Killian triangle. ZD is associated with dysphagia, regurgitation, cough and recurrent aspirations. Open surgical repair has been the traditional treatment approach but has high morbidity (0-40%) and mortality (0-9.5%). Endoscopic intervention with septotomy is a less invasive approach with lower complications and shorter recovery times. However, technical success rates range between 56.4-100%, and recurrences occur in 0-32% of patients. Recent studies have shown promising results for peroral endoscopic myotomy treatment of ZD (Z-POEM), although data is limited.

Aims
In this first Canadian case series, we assess the safety and efficacy of Z-POEM, a novel approach for managing ZD.

Methods
This is a retrospective case series of all patients who underwent Z-POEM for ZD at Kingston Health Sciences center between July 2021-2023. Data collected included patient demographics, symptoms [Kothari Haber Score (KHS)] pre and post Z-POEM, ZD size and prior treatments. Technical outcomes were also analyzed including the procedure time and the Z-POEM Difficulty Score (ZPDS), which ranges from 0-3 based on maneuverability, fibrosis, and oozing. Clinical success was defined as complete or near-complete resolution of symptoms (i.e. KHS ampersand:003C2), and recurrence was defined as KHS of 3 or more. Lastly, we recorded adverse events and hospital length of stay.

Results
This case series included 9 patients (6 males and 3 females). The mean age ± standard deviation (SD) was 66.1 ± 10.64 years. One patient had two separate Z-POEM procedures and those were analyzed separately (total sample size = 10). The mean duration of symptoms before the procedure was 31.2 ± 10.12 months and the mean size of ZD was 2.25 ± 1.10 cm. Two patients had prior treatments before their Z-POEM procedure. The median preprocedural KHS was 6 (range 3-10) with dysphagia being the most commonly reported symptom in 80% of patients. In terms of technical outcomes, the mean procedural time was 32.3 ± 13.21 mins, and the median ZPDS score was 2. Most patients required 4-6 clips, with one patient requiring 11 clips for closure. No adverse events or periprocedural complications were reported. 9/10 patients (90%) were discharged one day after the procedure, and one patient required a longer stay (4 days) for observation. Clinical success was achieved in 8/10 patients (80%) of patients with a KHS score of 0 at mean 12 months follow-up. The remaining two patients (20%) had a KHS score of 3 at follow-up suggesting some persistent symptoms.

Conclusions
Z-POEM is safe and effective in management of ZD with high technical and clinical success rates in the short-term. Larger-scale studies are required to determine the long-term clinical efficacy of Z-POEM in treatment of ZD.

Funding Agencies
None