Autonomous Artificial Intelligence vs Artificial Intelligence-Assisted Human Optical Diagnosis of Colorectal Polyps: A Randomized Controlled Trial.

BACKGROUND & AIMS: Artificial intelligence (AI)-based optical diagnosis systems (CADx) have been developed to allow pathology prediction of colorectal polyps during colonoscopies. However, CADx systems have not yet been validated for autonomous performance. Therefore, we conducted a trial comparing autonomous AI to AI-assisted human (AI-H) optical diagnosis. METHODS: We performed a randomized noninferiority trial of patients undergoing elective colonoscopies at 1 academic institution. Patients were randomized into (1) autonomous AI-based CADx optical diagnosis of diminutive polyps without human input or (2) diagnosis by endoscopists who performed optical diagnosis of diminutive polyps after seeing the real-time CADx diagnosis. The primary outcome was accuracy in optical diagnosis in both arms using pathology as the gold standard. Secondary outcomes included agreement with pathology for surveillance intervals. RESULTS: A total of 467 patients were randomized (238 patients/158 polyps in the autonomous AI group and 229 patients/179 polyps in the AI-H group). Accuracy for optical diagnosis was 77.2% (95% confidence interval [CI], 69.7-84.7) in the autonomous AI group and 72.1% (95% CI, 65.5-78.6) in the AI-H group (P = .86). For high-confidence diagnoses, accuracy for optical diagnosis was 77.2% (95% CI, 69.7-84.7) in the autonomous AI group and 75.5% (95% CI, 67.9-82.0) in the AI-H group. Autonomous AI had statistically significantly higher agreement with pathology-based surveillance intervals compared to AI-H (91.5% [95% CI, 86.9-96.1] vs 82.1% [95% CI, 76.5-87.7]; P = .016). CONCLUSIONS: Autonomous AI-based optical diagnosis exhibits noninferior accuracy to endoscopist-based diagnosis. Both autonomous AI and AI-H exhibited relatively low accuracy for optical diagnosis; however, autonomous AI achieved higher agreement with pathology-based surveillance intervals. (ClinicalTrials.gov, Number NCT05236790).

Environmental impact of single-use versus reusable gastroscopes.

INTRODUCTION: The environmental impact of endoscopy is a topic of growing interest. This study aimed to compare the carbon footprint of performing an esogastroduodenoscopy (EGD) with a reusable (RU) or with a single-use (SU) disposable gastroscope. METHODS: SU (Ambu aScope Gastro) and RU gastroscopes (Olympus, H190) were evaluated using life cycle assessment methodology (ISO 14040) including the manufacture, distribution, usage, reprocessing and disposal of the endoscope. Data were obtained from Edouard Herriot Hospital (Lyon, France) from April 2023 to February 2024. Primary outcome was the carbon footprint (measured in Kg CO2 equivalent) for both gastroscopes per examination. Secondary outcomes included other environmental impacts. A sensitivity analysis was performed to examine the impact of varying scenarios. RESULTS: Carbon footprint of SU and RU gastroscopes were 10.9 kg CO2 eq and 4.7 kg CO2 eq, respectively. The difference in carbon footprint equals one conventional car drive of 28 km or 6 days of CO2 emission of an average European household. Based on environmentally-extended input-output life cycle assessment, the estimated per-use carbon footprint of the endoscope stack and washer was 0.18 kg CO2 eq in SU strategy versus 0.56 kg CO2 eq in RU strategy. According to secondary outcomes, fossil eq depletion was 130 MJ (SU) and 60.9 MJ (RU) and water depletion for 6.2 m3 (SU) and 9.5 m3 (RU), respectively. CONCLUSION: For one examination, SU gastroscope have a 2.5 times higher carbon footprint than RU ones. These data will help with the logistics and planning of an endoscopic service in relation to other economic and environmental factors.

Cold Snare Resection in the Colorectum: When to Choose it, When to Avoid it, and How to Do it.

Cold snaring is now the preferred resection method for the majority of colorectal polyps encountered during colonoscopy. A key advantage of cold resection over resection utilizing electrocautery is a substantially lower risk of delayed hemorrhage. Cold snare resection is preferred for all lesions ≤10 mm and for nondysplastic sessile serrated lesions of any size but should be avoided when lesions have a significant risk of submucosal invasion or fibrosis. Cold snare resection can be considered for certain lesions 11-19 mm in size and some lateral spreading lesions ≥20 mm. This review discusses tips and techniques to optimize cold snare resection.

Using Computer-aided Optical Diagnosis and Expert Review to Evaluate Colorectal Polyps Diagnosed as Normal Mucosa in Pathology.

Pathological assessment of colorectal polyps is considered the current reference standard for histologic diagnosis. About 10% of polyps sent to the pathology lab are returned with the diagnosis of mucosal folds, mucosal prolapse, or normal mucosa.1,2 Two recent publications have indicated that disagreements between endoscopic optical diagnosis and the subsequent pathological diagnoses might be due to misdiagnosis in pathology.3,4 We were therefore interested in re-evaluating pathology-based diagnosis of "mucosal polyps" using expert endoscopists and computer-assisted diagnosis (CADx) evaluation.

Snare Tip Soft Coagulation vs Argon Plasma Coagulation vs No Margin Treatment After Large Nonpedunculated Colorectal Polyp Resection: a Randomized Trial.

BACKGROUND & AIMS: Thermal treatment of the defect margin after endoscopic mucosal resection (EMR) of large nonpedunculated colorectal lesions reduces the recurrence rate. Both snare tip soft coagulation (STSC) and argon plasma coagulation (APC) have been used for thermal margin treatment, but there are few data directly comparing STSC with APC for this indication. METHODS: We performed a randomized 3-arm trial in 9 US centers comparing STSC with APC with no margin treatment (control) of defects after EMR of colorectal nonpedunculated lesions ≥15 mm. The primary end point was the presence of residual lesion at first follow-up. RESULTS: There were 384 patients and 414 lesions randomized, and 308 patients (80.2%) with 328 lesions completed ≥1 follow-up. The proportion of lesions with residual polyp at first follow-up was 4.6% with STSC, 9.3% with APC, and 21.4% with control subjects (no margin treatment). The odds of residual polyp at first follow-up were lower for STSC and APC when compared with control subjects (P = .001 and P = .01, respectively). The difference in odds was not significant between STSC and APC. STSC took less time to apply than APC (median, 3.35 vs 4.08 minutes; P = .019). Adverse event rates were low, with no difference between arms. CONCLUSIONS: In a randomized trial STSC and APC were each superior to no thermal margin treatment after EMR. STSC was faster to apply than APC. Because STSC also results in lower cost and plastic waste than APC (APC requires an additional device), our study supports STSC as the preferred thermal margin treatment after colorectal EMR. (Clinicaltrials.gov, Number NCT03654209.).

Development and initial validation of a video-based peroral endoscopic myotomy assessment tool.

BACKGROUND AND AIMS: Video analysis has emerged as a potential strategy for performance assessment and improvement. We aimed to develop a video-based skill assessment tool for peroral endoscopic myotomy (POEM). METHODS: POEM was deconstructed into basic procedural components through video analysis by an expert panel. A modified Delphi approach and 2 validation exercises were conducted to refine the POEM assessment tool (POEMAT). Twelve assessors used the final POEMAT version to grade 10 videos. Fully crossed generalizability (G) studies investigated the contributions of assessors, endoscopists' performance, and technical elements to reliability. G coefficients below .5 were considered unreliable, between .5 and .7 as modestly reliable, and above .7 as indicative of satisfactory reliability. RESULTS: After task deconstruction, discussions, and the modified Delphi process, the final POEMAT comprised 9 technical elements. G analysis showed low variance for endoscopist performance (.8%-24.9%) and high interrater variability (range, 63.2%-90.1%). The G score was moderately reliable (≥.60) for "submucosal tunneling" and "myotomy" and satisfactorily reliable (≥.70) for "active hemostasis" and "mucosal closure." CONCLUSIONS: We developed and established initial content and response process validity evidence for the POEMAT. Future steps include appraisal of the tool using a wider range of POEM videos to establish and improve the discriminative validity of this tool.

The environmental impact of small-bowel capsule endoscopy.

INTRODUCTION: The environmental impact of endoscopy, including small-bowel capsule endoscopy (SBCE), is a topic of growing attention and concern. This study aimed to evaluate the greenhouse gas (GHG) emissions (kgCO2) generated by an SBCE procedure. METHODS: Life cycle assessment methodology (ISO 14040) was used to evaluate three brands of SBCE device and included emissions generated by patient travel, bowel preparation, capsule examination, and video recording. A survey of 87 physicians and 120 patients was conducted to obtain data on travel, activities undertaken during the procedure, and awareness of environmental impacts. RESULTS: The capsule itself (4 g) accounted for < 6 % of the total product weight. Packaging (43-119 g) accounted for 9 %-97 % of total weight, and included deactivation magnets (5 g [4 %-6 %]) and paper instructions (11-50 g [up to 40 %]). A full SBCE procedure generated approximately 20 kgCO2, with 0.04 kgCO2 (0.2 %) attributable to the capsule itself and 18 kgCO2 (94.7 %) generated by patient travel. Capsule retrieval using a dedicated device would add 0.98 kgCO2 to the carbon footprint. Capsule deconstruction revealed materials (e. g. neodymium) that are prohibited from environmental disposal; 76 % of patients were not aware of the illegal nature of capsule disposal via wastewater, and 63 % would have been willing to retrieve it. The carbon impact of data storage and capsule reading was negligible. CONCLUSION: The carbon footprint of SBCE is mainly determined by patient travel. The capsule device itself has a relatively low carbon footprint. Given that disposal of capsule components via wastewater is illegal, retrieval of the capsule is necessary but would likely be associated with an increase in device-related emissions.

Perspectives and awareness of endoscopy healthcare professionals on sustainable practices in gastrointestinal endoscopy: results of the LEAFGREEN survey.

BACKGROUND: Gastrointestinal (GI) endoscopy is one of healthcare's main contributors to climate change. We aimed to assess healthcare professionals' attitudes and the perceived barriers to implementation of sustainable GI endoscopy. METHODS: The LEAFGREEN web-based survey was a cross-sectional study conducted by the European Society of Gastrointestinal Endoscopy (ESGE) Green Endoscopy Working Group. The questionnaire comprised 39 questions divided into five sections (respondent demographics; climate change and sustainability beliefs; waste and resource management; single-use endoscopes and accessories; education and research). The survey was available via email to all active members of the ESGE and the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) in March 2023. RESULTS: 407 respondents participated in the survey (11% response rate). Most participants (86%) agreed climate change is real and anthropogenic, but one-third did not consider GI endoscopy to be a significant contributor to climate change. Improvement in the appropriateness of endoscopic procedures (41%) and reduction in single-use accessories (34%) were considered the most important strategies to reduce the environmental impact of GI endoscopy. Respondents deemed lack of institutional support and knowledge from staff to be the main barriers to sustainable endoscopy. Strategies to reduce unnecessary GI endoscopic procedures and comparative studies of single-use versus reusable accessories were identified as research priorities. CONCLUSIONS: In this survey, ESGE and ESGENA members acknowledge climate change as a major threat to humanity. Further improvement in sustainability beliefs and professional attitudes, reduction in inappropriate GI endoscopy, and rational use of single-use accessories and endoscopes are critically required.

Local recurrence rates after resection of large colorectal serrated lesions with or without margin thermal ablation.

INTRODUCTION: Serrated lesions (SLs) including traditional serrated adenomas (TSA), large hyperplastic polyps (HP) and sessile serrated lesions (SSLs) are associated with high incomplete resection rates. Margin ablation combined with EMR (EMR-T) has become routine to reduce local recurrence while cold snare polypectomy (CSP) is becoming recognized as equally effective for large SLs. Our aim was to evaluate local recurrence rates (LRR) and the use of margin ablation in preventing recurrence in a retrospective cohort study. METHODS: Patients undergoing resection of ≥15 mm colorectal SLs from 2010-2022 were identified through a pathology database and electronic medical records search. Hereditary CRC syndromes, first follow-up > 18 months or no follow-up, surgical resection were excluded. Primary outcome was LRRs (either histologic or visual) during the first 18-month follow-up. Secondary outcomes were LRRs according to size, and resection technique. RESULTS: 191 polyps in 170 patients were resected (59.8% women; mean age, 65 years). The mean size of polyps was 22.4 mm, with 107 (56.0%) ≥20 mm. 99 polyps were resected with EMR, 39 with EMR-T, and 26 with CSP. Mean first surveillance was 8.2 mo. Overall LRR was 18.8% (36/191) (16.8% for ≥20 mm, 17.9% for ≥30 mm). LRR was significantly lower after EMR-T when compared with EMR (5.1% vs. 23.2%; p = 0.013) or CSP (5.1% vs. 23.1%; p = 0.031). There was no difference in LRR between EMR without margin ablation and CSP (p = 0.987). CONCLUSION: The local recurrence rate for SLs ≥15 mm is high with 18.8% overall recurrence. EMR with thermal ablation of the margins is superior to both no ablation and CSP in reducing LRRs.

Effect of fecal immunochemical test cut-off levels on adenoma detection rate: a systematic review and meta-analysis.

BACKGROUND: Adenoma detection rate (ADR) is higher after a positive fecal immunochemical test (FIT) compared to direct screening colonoscopy. OBJECTIVE: This meta-analysis evaluated how ADR, the rates of advanced adenoma detection (AADR), colorectal cancer detection (CDR), and sessile serrated lesion detection (SSLDR) are affected by different FIT positivity thresholds. METHODS: We searched MEDLINE, EMBASE, CINAHL, and EBM Reviews databases for studies reporting ADR, AADR, CDR, and SSLDR according to different FIT cut-off values in asymptomatic average-risk individuals aged 50-74 years old. Data were stratified according to sex, age, time to colonoscopy, publication year, continent, and FIT kit type. Study quality, heterogeneity, and publication bias were assessed. RESULTS: Overall, 4280 articles were retrieved and fifty-eight studies were included (277,661 FIT-positive colonoscopies; mean cecal intubation 96.3%; mean age 60.8 years; male 52.1%). Mean ADR was 56.1% (95% CI 53.4 - 58.7%), while mean AADR, CDR, and SSLDR were 27.2% (95% CI 24.4 - 30.1%), 5.3% (95% CI 4.7 - 6.0%), and 3.0% (95% CI 1.7 - 4.6%), respectively. For each 20 µg Hb/g increase in FIT cut-off level, ADR increased by 1.54% (95% CI 0.52 - 2.56%, p < 0.01), AADR by 3.90% (95% CI 2.76 - 5.05%, p < 0.01) and CDR by 1.46% (95% CI 0.66 - 2.24%, p < 0.01). Many detection rates were greater amongst males and Europeans. CONCLUSIONS: ADRs in FIT-positive colonoscopies are influenced by the adopted FIT positivity threshold, and identified targets, importantly, proved to be higher than most current societal recommendations.

Expert endoscopist assessment of colorectal polyp size using virtual scale endoscopy, visual or snare-based estimation: a prospective video-based study.

BACKGROUND AND AIMS: Accurate polyp size estimation during colonoscopy has an impact on clinical decision-making. A laser-based virtual scale endoscope (VSE) is available to allow measuring polyp size using a virtual adaptive scale. This study evaluates video-based polyp size measurement accuracy among expert endoscopists using either VSE or visual assessment (VA) with either snare as reference size or without any reference size information. METHODS: A prospective, video-based study was conducted with 10 expert endoscopists. Video sequences from 90 polyps with known reference size (fresh specimen measured using calipers) were distributed on three different slide sets so that each slide set showed the same polyp only once with either VSE, VA or snare-based information. A slide set was randomly assigned to each endoscopist. Endoscopists were asked to provide size estimation based on video review. RESULTS: Relative accuracies for VSE, VA, and snare-based estimation were 75.1% (95% CI [71.6-78.5]), 65.0% (95% CI [59.5-70.4]) and 62.0% (95% CI [54.8-69.0]), respectively. VSE yielded significantly higher relative accuracy compared to VA (p = 0.002) and to snare (p = 0.001). A significantly lower percentage of polyps 1-5 mm were misclassified as >5 mm using VSE versus VA and snare (6.52% vs. 19.6% and 17.5%, p = 0.004) and a significantly lower percentage of polyps >5 mm were misclassified as 1-5 mm using VSE versus VA and snare (11.4% vs. 31.9% and 14.9%, p = 0.038). CONCLUSIONS: Endoscopists estimate polyp size with the highest accuracy when virtual adaptive scale information is displayed. Using a snare to assist sizing did not improve measurement accuracy compared to displaying visual information alone.

Harlequin syndrome in a patient with probable hemicrania continua and exertional headache - is there a link? a case report.

BACKGROUND: The harlequin syndrome is a rare disorder of the autonomic nervous system characterized by unilateral diminished flushing and sweating of the face following exposure to heat or physical activity. It results from sympathetic dysfunction and most commonly occurs idiopathically. A secondary development due to an underlying pathology (e.g., carotid artery dissection, tumors) must be excluded at first appearance. There is evidence that the cranial autonomic system is involved in the pathophysiology of trigeminal autonomic headaches like hemicrania continua. Therefore, an overlap in the pathophysiology of harlequin syndrome and trigeminal autonomic headache disorders seems plausible. However, the association of a harlequin syndrome with hemicrania continua was never reported. CASE PRESENTATION: This work describes the case of a 42-year-old female patient presenting to our headache unit. The patient reported persisting unilateral headache of the right side of dragging or squeezing character accompanied by trigeminal autonomic symptoms, including lacrimation, nasal congestion, conjunctival injection and Horner's syndrome, and was responsive to treatment with 75mg/d indomethacin. Five months after the initial consultation, the patient noted that the upper right quadrant of her face was pale after jogging. A harlequin syndrome was diagnosed. Further, she developed a short-lasting, bilateral headache of pulsatile character during strenuous exercise consistent with exertional headache. Comprehensive diagnostic evaluations, encompassing cranial and cervical MRI scans, laboratory tests, and biopsies, culminated in the diagnosis of Sjögren's syndrome. This finding suggests that the trigemino-autonomic dysfunction may either be idiopathic or a direct manifestation of Sjögren's syndrome. CONCLUSIONS: This report documents the case of a rare combination of a headache resembling probable hemicrania continua and the harlequin syndrome (and even exertional headache). It illustrates the underlying anatomy of the autonomic nervous system in a clinical context and emphasizes the hypothesis of a pathophysiological link between abnormal sympathetic activity and trigeminal autonomic headaches.

Circadian functional changes of pain-processing brainstem nuclei and implications for cluster headache: A 7 Tesla imaging study.

BACKGROUND: Pain thresholds and primary headaches, including cluster headache attacks, have circadian rhythmicity. Thus, they might share a common neuronal mechanism. OBJECTIVE: This study aimed to elucidate how the modulation of nociceptive input in the brainstem changes from noon to midnight. Insights into the mechanism of these fluctuations could allow for new hypotheses about the pathophysiology of cluster headache. METHODS: This repeated measure observational study was conducted at the University Hospital Zurich from December 2019 to November 2022. Healthy adults between 18 and 85 years of age were eligible. All participants were examined at noon and midnight. We tested the pain threshold on both sides of the foreheads with quantitative sensory testing, assessed tiredness levels, and obtained high-field (7 Tesla) and high-resolution functional magnetic resonance imaging (MRI) at each visit. Functional connectivity was assessed at the two visits by performing a region-of-interest analysis. We defined nuclei in the brainstem implicated in processing nociceptive input as well as the thalamus and suprachiasmatic nucleus as the region-of-interest. RESULTS: Ten people were enrolled, and seven participants were included. First, we did not find statistically significant differences between noon and midnight of A-delta-mediated pain thresholds (median mechanical pain threshold at noon: left 9.2, right 9.2; at night: left 6.5, right 6.1). Second, after correction for a false discovery rate, we found changes in the mechanical pain sensitivity to have a statistically significant effect on changes in the functional connectivity between the left parabrachial nucleus and the suprachiasmatic nucleus (T = -40.79). CONCLUSION: The MRI data analysis suggested that brain stem nuclei and the hypothalamus modulate A-delta-mediated pain perception; however, these changes in pain perception did not lead to statistically significantly differing pain thresholds between noon and midnight. Hence, our findings shed doubt on our hypothesis that the physiologic circadian rhythmicity of pain thresholds could drive the circadian rhythmicity of cluster headache attacks.

International consensus on the management of large (≥20 mm) colorectal laterally spreading tumors: World Endoscopy Organization Delphi study.

OBJECTIVES: There have been significant advances in the management of large (≥20 mm) laterally spreading tumors (LSTs) or nonpedunculated colorectal polyps; however, there is a lack of clear consensus on the management of these lesions with significant geographic variability especially between Eastern and Western paradigms. We aimed to provide an international consensus to better guide management and attempt to homogenize practices. METHODS: Two experts in interventional endoscopy spearheaded an evidence-based Delphi study on behalf of the World Endoscopy Organization Colorectal Cancer Screening Committee. A steering committee comprising six members devised 51 statements, and 43 experts from 18 countries on six continents participated in a three-round voting process. The Grading of Recommendations, Assessment, Development and Evaluations tool was used to assess evidence quality and recommendation strength. Consensus was defined as ≥80% agreement (strongly agree or agree) on a 5-point Likert scale. RESULTS: Forty-two statements reached consensus after three rounds of voting. Recommendations included: three statements on training and competency; 10 statements on preresection evaluation, including optical diagnosis, classification, and staging of LSTs; 14 statements on endoscopic resection indications and technique, including statements on en bloc and piecemeal resection decision-making; seven statements on postresection evaluation; and eight statements on postresection care. CONCLUSIONS: An international expert consensus based on the current available evidence has been developed to guide the evaluation, resection, and follow-up of LSTs. This may provide guiding principles for the global management of these lesions and standardize current practices.

The prevalence of head and face pain decreased from 1997 to 2017 in Switzerland.

BACKGROUND: Pain in the head and the face is highly prevalent but may have changed during the past years. This study aimed to analyze changes in the prevalence of pain in the head and the face in Switzerland from 1997 to 2017. METHODS: This is a secondary analysis of data collected in the Swiss Health Surveys of 1997-2017. Included persons were 15 years and older. Besides studying demographic data, we analyze the item assessing the presence of "headache, pressure in the head, or facial pain" during the past 4 weeks. Percentages with their Wilson confidence intervals are reported for each response option of categorical variables. Moreover, we calculate the age-standardized number of persons affected by the pain. RESULTS: While 41% reported head and face pain in 1997, the proportion dropped to 31% in 2017. There was a decrease of 19.5% in women and 29.4% in men; after age standardization, the decrease was 16.5% in women and 25.4% in men. The most considerable numerical changes in the percentages of women with pain occurred in those aged 55-69 and 85 and above. In men, the changes were not limited to specific age groups. CONCLUSIONS: The proportion of people reporting headaches, pressure in the head, or facial pain has dropped in Switzerland from 1997 to 2017. However, in women, the prevalence diminished more strongly and consistently in the middle-aged and the elderly than in the young.

The longitudinal influence of tDCS on occipital GABA and glutamate/glutamine levels in episodic migraineurs.

This study investigated differences in the concentration of gamma-aminobutyric acid (GABA) and the combination of glutamine and glutamate (as GLX) in the early visual cortex of patients with episodic migraine and the influence of transcranial direct current stimulation (tDCS) on GABA and GLX. In this single-blind, sham-controlled trial, we randomly assigned patients with episodic migraine to receive daily anodal tDCS or sham stimulation. In addition, we included healthy controls. We acquired proton MR spectroscopy data of the visual cortex with 3 Tesla MRI at baseline and from migraine patients directly after the stimulation period and 4 months later. In 22 migraineurs and 25 controls, the GABA and the GLX concentrations did not differ at baseline between the groups. tDCS resulted in reduced concentrations of GABA but not GLX or the migraine frequency directly after the stimulation period, but not 4 months later. The changes in the levels of GABA in the early visual cortex of patients with episodic migraine in the interictal period suggest an effect of tDCS that allowed for subsequent changes in the migraine frequency. However, we might have missed relevant variations in the concentrations of these neurotransmitters during the follow-up period, as changes in migraine frequency appeared after the first MRI and disappeared before the second.

Comparison of adenoma miss rate and adenoma detection rate between conventional colonoscopy and colonoscopy with second generation distal attachment cuff: a multicenter, randomized, back-to-back trial.

BACKGROUND AND AIMS: Endocuff VisionTM has been designed to enhance mucosal visualization thereby improving detection of (pre-)malignant colorectal lesions. This multicenter, international, back-to-back, randomized colonoscopy trial compared adenoma detection rate (ADR) and adenoma miss rate (AMR) between Endocuff Vision-assisted colonoscopy (EVC) and conventional colonoscopy (CC). METHODS: Patients aged 40-75 years referred for non-immunochemical fecal occult blood test-based screening, surveillance, or diagnostic colonoscopy were included at ten hospitals and randomized into four groups: Group 1; 2xCC, Group 2; CC followed by EVC, Group 3; EVC followed CC and Group 4; 2xEVC. Primary outcomes included ADR and AMR. RESULTS: A total of 717 patients were randomized of which 661 patients (92.2%) had one and 646 (90.1%) patients had two completed back-to-back colonoscopies. EVC did not significantly improve ADR compared to CC (41.1% [95%-CI;36.1-46.3] versus 35.5% [95%-CI;30.7-40.6], respectively, P=0.125), but EVC did reduced AMR by 11.7% (29.6% [95%-CI;23.6-36.5] versus 17.9% [95%-CI;12.5-23.5], respectively, P=0.049). AMR of 2xCC compared to 2xEVC was also not significantly different (25.9% [95%-CI;19.3-33.9] versus 18.8% [95%-CI;13.9-24.8], respectively, P=0.172). Only 3.7% of the polyps missed during the first procedures had advanced pathologic features. Factors affecting risk of missing adenomas were age (P=0.002), Boston Bowel Preparation Scale (P=0.008) and region where colonoscopy was performed (P<0.001). CONCLUSIONS: Our trial shows that EVC reduces the risk of missing adenomas but does not lead to a significant improved ADR. Remarkably, 25% of adenomas are still missed during conventional colonoscopies, which is not different from miss rates reported 25 years ago; reassuringly, advanced features were only found in 3.7% of these missed lesions. TRAIL REGISTRATION NUMBER: NCT03418948.

Novel through-the-scope suture closure of colonic EMR defects (with video).

BACKGROUND AND AIMS: Large colon polyps removed by EMR can be complicated by delayed bleeding. Prophylactic defect clip closure can reduce post-EMR bleeding. Larger defects can be challenging to close using through-the-scope clips (TTSCs), and proximal defects are difficult to reach using over-the-scope techniques. A novel, through-the-scope suturing (TTSS) device allows direct closure of mucosal defects without scope withdrawal. The goal of this study was to evaluate the rate of delayed bleeding after the closure of large colon polyp EMR sites with TTSS. METHODS: A multicenter retrospective cohort study was performed involving 13 centers. All defect closure by TTSS after EMR of colon polyps ≥2 cm from January 2021 to February 2022 were included. The primary outcome was rate of delayed bleeding. RESULTS: A total of 94 patients (52% female; mean age, 65 years) underwent EMR of predominantly right-sided (n = 62 [66%]) colon polyps (median size, 35 mm; interquartile range, 30-40 mm) followed by defect closure with TTSS during the study period. All defects were successfully closed with TTSS alone (n = 62 [66%]) or with TTSS and TTSCs (n = 32 [34%]), using a median of 1 (interquartile range, 1-1) TTSS system. Delayed bleeding occurred in 3 patients (3.2%), with 2 requiring repeated endoscopic evaluation/treatment (moderate). CONCLUSION: TTSS alone or with TTSCs was effective in achieving complete closure of all post-EMR defects, despite a large lesion size. After TTSS closure with or without adjunctive devices, delayed bleeding was seen in 3.2% of cases. Further prospective studies are needed to validate these findings before wider adoption of TTSS for large polypectomy closure.

Risk of total metachronous advanced neoplasia at surveillance colonoscopy after detection of serrated lesions: a matched case-cohort study.

BACKGROUND : Serrated lesions are potential colorectal cancer precursors. This study evaluated the presence of total metachronous advanced neoplasia (T-MAN) at follow-up in patients with index serrated lesions compared with a matched cohort without serrated lesions. METHODS : Patients aged 45-74 years with serrated lesions were matched 2:1 by sex, age, synchronous polyps, and timing of index colonoscopy, to patients without serrated lesions. The primary outcome was T-MAN (advanced adenoma or high-risk serrated lesion) at follow-up. Secondary outcomes included presence of T-MAN stratified by synchronous polyps and serrated lesion characteristics. RESULTS : 1425 patients were included (475 patients, 642 serrated lesions; 950 controls; median follow-up 2.9 versus 3.6 years). Patients with serrated lesions had greater risk of T-MAN than those without (hazard ratio [HR] 6.1, 95 %CI 3.9-9.6). Patients with serrated lesions and high-risk adenoma (HRA) had higher risk of T-MAN than those with HRA alone (HR 2.6, 95 %CI 1.4-4.7); similarly, patients with serrated lesions plus low-risk adenoma (LRA) had higher risk than those with LRA alone (HR 7.0, 95 %CI 2.8-18.4), as did patients with serrated lesions without adenoma compared with no adenoma (HR 14.9, 95 %CI 6.5-34.0). Presence of proximal sessile serrated lesion (SSL; HR 9.3, 95 %CI 5.4-15.9), large SSL (HR 17.8, 95 %CI 7.4-43.3), and proximal large SSL (HR 25.0, 95 %CI 8.8-71.3), but not distal SSL, were associated with greater risk for T-MAN. CONCLUSION : Patients with serrated lesions had higher risk for T-MAN regardless of synchronous adenomas. Patients with serrated lesions and HRA, and those with large or proximal SSLs, were at greatest risk.

Incomplete resection of colorectal polyps of 4-20 mm in size when using a cold snare, and its associated factors.

BACKGROUND : Cold snare polypectomy (CSP) is increasingly used for polypectomy and is recommended as the first-line modality for small (< 10 mm) polyps. This study aimed to evaluate incomplete resection rates (IRRs) when using CSP for colorectal polyps of 4-20 mm. METHODS : Adults (45-80 years) undergoing screening, surveillance, or diagnostic colonoscopy and CSP by one of nine endoscopists were included. The primary outcome was the IRR for colorectal polyps of 4-20 mm, defined as the presence of polyp tissue in marginal biopsies after resection of serrated polyps or adenomas. Secondary outcomes included the IRR for serrated polyps, ease of resection, and complications. RESULTS: 413 patients were included (mean age 63; 48 % women) and 182 polyps sized 4-20 mm were detected and removed by CSP. CSP required conversion to hot snare resection in < 1 % of polyps of < 10 mm and 44 % of polyps sized 10-20 mm. The IRRs for polyps < 10 mm and ≥ 10 mm were 18 % and 21 %. The IRR was higher for serrated polyps (26 %) compared with adenomas (16 %). The IRR was higher for flat (IIa) polyps (odds ratio [OR] 2.9, 95 %CI 1.1-7.4); and when resection was judged as difficult (OR 4.2, 95 %CI 1.5-12.1), piecemeal resection was performed (OR 6.6, 95 %CI 2.0-22.0), or visible residual polyp was present after the initial resection (OR 5.4, 95 %CI 2.0-14.9). Polyp location, use of a dedicated cold snare, and submucosal injection were not associated with incomplete resection. Intraprocedural bleeding requiring endoscopic intervention occurred in 4.7 %. CONCLUSIONS : CSP for polyps of 4-9 mm is safe and feasible; however, for lesions ≥ 10 mm, CSP failure occurs frequently, and the IRR remains high even after technical success. Incomplete resection was associated with flat polyps, visual residual polyp, piecemeal resection, and difficult polypectomies.