Recommendations for Follow-Up After Colonoscopy and Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer

High risk features in colorectal adenomatous polyps: A multi-institutional study

High risk features in colorectal adenomatous polyps include size >1 cm and advanced histology: high-grade dysplasia and villous architecture. We investigated whether the diagnostic rates of advanced histology in colorectal adenomatous polyps were similar among institutions across the United States, and if not, could differences be explained by patient age, polyp size, and/or CRC rate. Nine academic institutions contributed data from three pathologists who had signed out at least 100 colorectal adenomatous polyps each from 2018 to 2019 taken from patients undergoing screening colonoscopy. For each case, we recorded patient age and sex, polyp size and location, concurrent CRC, and presence or absence of HGD and villous features. A total of 2700 polyps from 1886 patients (mean age: 61 years) were collected. One hundred twenty-four (5 %) of the 2700 polyps had advanced histology, including 35 (1 %) with HGD and 101 (4 %) with villous features. The diagnostic rate of advanced histology varied by institution from 1.7 % to 9.3 % (median: 4.3 %, standard deviation [SD]: 2.5 %). The rate of HGD ranged from 0 % to 3.3 % (median: 1 %, SD: 1.2 %), while the rate of villous architecture varied from 1 % to 8 % (median: 3.7 %, SD: 2.5 %). In a multivariate analysis, the factor most strongly associated with advanced histology was polyp size >1 cm with an odds ratio (OR) of 31.82 (95 % confidence interval [CI]: 20.52-50.25, p < 0.05). Inter-institutional differences in the rate of polyps >1 cm likely explain some of the diagnostic variance, but pathologic subjectivity may be another contributing factor.

Long-term impact of artificial intelligence on colorectal adenoma detection in high-risk colonoscopy

BACKGROUND

Improved adenoma detection rate (ADR) has been demonstrated with artificial intelligence (AI)-assisted colonoscopy. However, data on the real-world application of AI and its effect on colorectal cancer (CRC) screening outcomes is limited.

AIM

To analyze the long-term impact of AI on a diverse at-risk patient population undergoing diagnostic colonoscopy for positive CRC screening tests or symptoms.

METHODS

AI software (GI Genius, Medtronic) was implemented into the standard procedure protocol in November 2022. Data was collected on patient demographics, procedure indication, polyp size, location, and pathology. CRC screening outcomes were evaluated before and at different intervals after AI introduction with one year of follow-up.

RESULTS

We evaluated 1008 colonoscopies (278 pre-AI, 255 early post-AI, 285 established post-AI, and 190 late post-AI). The ADR was 38.1% pre-AI, 42.0% early post-AI (P = 0.77), 40.0% established post-AI (P = 0.44), and 39.5% late post-AI (P = 0.77). There were no significant differences in polyp detection rate (PDR, baseline 59.7%), advanced ADR (baseline 16.2%), and non-neoplastic PDR (baseline 30.0%) before and after AI introduction.

CONCLUSION

In patients with an increased pre-test probability of having an abnormal colonoscopy, the current generation of AI did not yield enhanced CRC screening metrics over high-quality colonoscopy. Although the potential of AI in colonoscopy is undisputed, current AI technology may not universally elevate screening metrics across all situations and patient populations. Future studies that analyze different AI systems across various patient populations are needed to determine the most effective role of AI in optimizing CRC screening in clinical practice.

Distinctive Lipid Characteristics of Colorectal Cancer Revealed through Non-targeted Lipidomics Analysis of Tongue Coating

The metabolites and microbiota in tongue coating display distinct characteristics in certain digestive disorders, yet their relationship with colorectal cancer (CRC) remains unexplored. Here, we employed liquid chromatography coupled with tandem mass spectrometry to analyze the lipid composition of tongue coating using a nontargeted approach in 30 individuals with colorectal adenomas (CRA), 32 with CRC, and 30 healthy controls (HC). We identified 21 tongue coating lipids that effectively distinguished CRC from HC (AUC = 0.89), and 9 lipids that differentiated CRC from CRA (AUC = 0.9). Furthermore, we observed significant alterations in the tongue coating lipid composition in the CRC group compared to HC/CRA groups. As the adenoma-cancer sequence progressed, there was an increase in long-chain unsaturated triglycerides (TG) levels and a decrease in phosphatidylethanolamine plasmalogen (PE-P) levels. Furthermore, we noted a positive correlation between N-acyl ornithine (NAOrn), sphingomyelin (SM), and ceramide phosphoethanolamine (PE-Cer), potentially produced by members of the Bacteroidetes phylum. The levels of inflammatory lipid metabolite 12-HETE showed a decreasing trend with colorectal tumor progression, indicating the potential involvement of tongue coating microbiota and tumor immune regulation in early CRC development. Our findings highlight the potential utility of tongue coating lipid analysis as a noninvasive tool for CRC diagnosis.

Single-center experience with intraprocedural cleansing system to improve inadequate bowel preparation during colonoscopy

Inadequate bowel preparation is common despite various preprocedure interventions. There is a need for an intervention at the time of colonoscopy to combat poor preparation. In this retrospective, observational study of 46 patients, we evaluated the clinical efficacy and feasibility of implementing the third generation of the Pure-Vu EVS System, a US Food and Drug Administration-cleared over-the-scope-based intraprocedural cleansing device, into our practice at the Minneapolis VA Medical Center (Minneapolis, Minnesota, United States). To study clinical efficacy, we measured bowel preparation adequacy before and after using the device, as measured by the Boston Bowel Preparation Score, and reviewed colonoscopy surveillance interval recommendations. Technical success and feasibility of using the device were measured by procedure success rates and duration. We found that BBPS scores increased from 4.4 to 7.9 when using the device. Technical success was achieved 78.3% of the time (36/46 cases). Median colonoscopy duration was 46 minutes, although there was a trend toward shorter procedures over time. This is the first clinical evaluation of the third generation of an intraprocedural cleansing device. We found the device efficacious and easy to use with low procedure failure rates, but it does come with a learning curve. We suspect that adoption of this device mutually will benefit patients and health systems with the potential to improve resource utilization.

Lead Time and Immortal Time Biases Impact the Calculation of Post-colonoscopy Colorectal Cancer Survival

The World Endoscopy Organization (WEO) standardized the reporting of post-colonoscopy colorectal cancers (PCCRCs), which account for 7% to 10% of colorectal cancers (CRCs).1 PCCRCs are diagnosed 6 to 36 months after a false negative colonoscopy. Detected CRCs (dCRCs) are diagnosed ≤6 months after an index true positive colonoscopy.2 PCCRC prognosis is unclear, with outcomes reported as comparable,3 superior,4 or inferior5,6 to those of dCRC. Because WEO terminology defines cases relative to the index colonoscopy, conventional survival analyses of PCCRC are susceptible to lead time and immortal time biases. We evaluated the influence of these biases on mortality in a population-based retrospective cohort of 10,938 dCRCs (93.8%) and 717 PCCRCs (6.2%). This study was set within Kaiser Permanente Northern California (KPNC), a large integrated health system, whose members are similar in demographic and socioeconomic characteristics to the Northern California region.7.

ChatGPT4 Outperforms Endoscopists for Determination of Postcolonoscopy Rescreening and Surveillance Recommendations

BACKGROUND & AIMS

Large language models including Chat Generative Pretrained Transformers version 4 (ChatGPT4) improve access to artificial intelligence, but their impact on the clinical practice of gastroenterology is undefined. This study compared the accuracy, concordance, and reliability of ChatGPT4 colonoscopy recommendations for colorectal cancer rescreening and surveillance with contemporary guidelines and real-world gastroenterology practice.

METHODS

History of present illness, colonoscopy data, and pathology reports from patients undergoing procedures at 2 large academic centers were entered into ChatGPT4 and it was queried for the next recommended colonoscopy follow-up interval. Using the McNemar test and inter-rater reliability, we compared the recommendations made by ChatGPT4 with the actual surveillance interval provided in the endoscopist's procedure report (gastroenterology practice) and the appropriate US Multisociety Task Force (USMSTF) guidance. The latter was generated for each case by an expert panel using the clinical information and guideline documents as reference.

RESULTS

Text input of de-identified data into ChatGPT4 from 505 consecutive patients undergoing colonoscopy between January 1 and April 30, 2023, elicited a successful follow-up recommendation in 99.2% of the queries. ChatGPT4 recommendations were in closer agreement with the USMSTF Panel (85.7%) than gastroenterology practice recommendations with the USMSTF Panel (75.4%) (P < .001). Of the 14.3% discordant recommendations between ChatGPT4 and the USMSTF Panel, recommendations were for later screening in 26 (5.1%) and for earlier screening in 44 (8.7%) cases. The inter-rater reliability was good for ChatGPT4 vs USMSTF Panel (Fleiss κ, 0.786; 95% CI, 0.734-0.838; P < .001).

CONCLUSIONS

Initial real-world results suggest that ChatGPT4 can define routine colonoscopy screening intervals accurately based on verbatim input of clinical data. Large language models have potential for clinical applications, but further training is needed for broad use.

Longer Interval Between First Colonoscopy With Negative Findings for Colorectal Cancer and Repeat Colonoscopy

Importance

For individuals without a family history of colorectal cancer (CRC), colonoscopy screening every 10 years is recommended to reduce CRC incidence and mortality. However, debate exists about whether and for how long this 10-year interval could be safely expanded.

Objective

To assess how many years after a first colonoscopy with findings negative for CRC a second colonoscopy can be performed.

Design, Setting, and Participants

This cohort study leveraged Swedish nationwide register-based data to examine CRC diagnoses and CRC-specific mortality among individuals without a family history of CRC. The exposed group included individuals who had a first colonoscopy with findings negative for CRC at age 45 to 69 years between 1990 and 2016. The control group included individuals matched by sex, birth year, and baseline age (ie, the age of their matched exposed individual when the exposed individual's first colonoscopy with findings negative for CRC was performed). Individuals in the control group either did not have a colonoscopy during the follow-up or underwent colonoscopy that resulted in a CRC diagnosis. Up to 18 controls were matched with each exposed individual. Individuals were followed up from 1990 to 2018, and data were analyzed from November 2022 to November 2023.

Exposure

A first colonoscopy with findings negative for CRC, defined as a first colonoscopy without a diagnosis of colorectal polyp, adenoma, carcinoma in situ, or CRC before or within 6 months after screening.

Main Outcomes and Measures

The primary outcomes were CRC diagnosis and CRC-specific death. The 10-year standardized incidence ratio and standardized mortality ratio were calculated to compare risks of CRC and CRC-specific death in the exposed and control groups based on different follow-up screening intervals.

Results

The sample included 110 074 individuals (65 147 females [59.2%]) in the exposed group and 1 981 332 (1 172 646 females [59.2%]) in the control group. The median (IQR) age for individuals in both groups was 59 (52-64) years. During up to 29 years of follow-up of individuals with a first colonoscopy with findings negative for CRC, 484 incident CRCs and 112 CRC-specific deaths occurred. After a first colonoscopy with findings negative for CRC, the risks of CRC and CRC-specific death in the exposed group were significantly lower than those in their matched controls for 15 years. At 15 years after a first colonoscopy with findings negative for CRC, the 10-year standardized incidence ratio was 0.72 (95% CI, 0.54-0.94) and the 10-year standardized mortality ratio was 0.55 (95% CI, 0.29-0.94). In other words, the 10-year cumulative risk of CRC in year 15 in the exposed group was 72% that of the 10-year cumulative risk of CRC in the control group. Extending the colonoscopy screening interval from 10 to 15 years in individuals with a first colonoscopy with findings negative for CRC could miss the early detection of only 2 CRC cases and the prevention of 1 CRC-specific death per 1000 individuals, while potentially avoiding 1000 colonoscopies.

Conclusions and Relevance

This cohort study found that for the population without a family history of CRC, the 10-year interval between colonoscopy screenings for individuals with a first colonoscopy with findings negative for CRC could potentially be extended to 15 years. A longer interval between colonoscopy screenings could be beneficial in avoiding unnecessary invasive examinations.

GI genius endoscopy module: a clinical profile

INTRODUCTION

The identification of early-stage colorectal cancers (CRC) and the resection of pre-cancerous neoplastic lesions through colonoscopy allows to decrease both CRC incidence and mortality. However, colonoscopy miss rates up to 26% for adenomas and 9% for advanced adenomas have been reported. In recent years, artificial intelligence (AI) systems have been emerging as easy-to-use tools, potentially lowering the risk of missing lesions.

AREAS COVERED

This review paper focuses on GI Genius device (Medtronic Co. Minneapolis, MN, U.S.A.) a computer-assisted tool designed to assist endoscopists during standard white-light colonoscopies in detecting mucosal lesions.

EXPERT OPINION

Randomized controlled trials (RCTs) suggest that GI Genius is a safe and effective tool for improving adenoma detection, especially in CRC screening and surveillance colonoscopies. However, its impact seems to be less significant among experienced endoscopists and in real-world clinical scenarios compared to the controlled conditions of RCTs. Furthermore, it appears that GI Genius mainly enhances the detection of non-advanced, small polyps, but does not significantly impact the identification of advanced and difficult-to-detect adenoma. When using GI Genius, no complications were documented. Only a small number of studies reported an increased in withdrawal time or the removal of non-neoplastic lesions.

A population-based analysis on the incidence of metachronous colon cancer after endoscopic resection of advanced adenomas with high-grade dysplasia: does location matter?

BACKGROUND

Advanced adenomas (AAs) with high-grade dysplasia (HGD) represent a risk factor for metachronous neoplasia, with guidelines recommending short-interval surveillance. Although the worse prognosis of proximal (vs distal) colon cancers (CCs) is established, there is paucity of evidence on the impact of laterality on the risk of subsequent neoplasia for these AAs.

METHODS

Adults with HGD adenomas undergoing polypectomy were identified in the Surveillance, Epidemiology, and End Results database (2000-2019). Cumulative incidence of malignancy was estimated using the Kaplan-Meier method. Fine-Gray models assessed the effect of patient and disease characteristics on CC incidence.

RESULTS

Of 3199 patients, 26% had proximal AAs. A total of 65 cases of metachronous adenocarcinoma were identified after polypectomy of 35 proximal and 30 distal adenomas with HGD. The 10-year cumulative incidence of CC was 2.3%; when stratified by location, it was 4.8% for proximal vs 1.4% for distal adenomas. Proximal location was significantly associated with increased incidence of metachronous cancer (adjusted hazard ratio, 3.32; 95% CI, 2.05-5.38).

CONCLUSION

Proximal location of AAs with HGD was associated with >3-fold increased incidence of metachronous CC and shorter time to diagnosis. These data suggest laterality should be considered in the treatment and follow-up of these patients.

Influence of Colorectal Cancer Risk Factors on Predictive Value of a Positive Multitarget Stool DNA Test

GOALS

We analyzed if the predictive value of multitarget stool-based DNA (mt-sDNA) varied when patients had pre-existing known colorectal cancer (CRC) risk factors.

BACKGROUND

mt-sDNA test is approved for CRC screening in average-risk patients. Whether patients with a personal history of adenomatous colon polyps or a family history of CRC (CRC risk factors) benefit from mt-sDNA testing is unknown.

STUDY

We reviewed charts for all positive mt-sDNA referrals between 2017 and 2021. Diagnostic colonoscopy adherence rates were calculated. In those who had colonoscopy, we compared detection rates for any colorectal neoplasia (CRN), multiple (3 or more) adenomas, sessile serrated polyps (SSP), advanced CRN, and CRC between patients with and without known CRC risk factors.

RESULTS

Of 1297 referrals for positive mt-sDNA, 1176 (91%) completed a diagnostic colonoscopy. The absence of neoplasia was noted in 27% of colonoscopy exams. When neoplasia was identified, findings were as follows: any CRN (73%), multiple adenomas (34%), SSP (23%), advanced CRN (33%), and CRC (2.5%). One or more CRC risk factors were present in 229 (19%) of cases. In the CRC risk factor subgroup, patients having a prior history of adenomatous polyps or a family history of CRC were no more likely to have any CRN, multiple adenomas, SSP, advanced CRN, or CRC compared to average-risk patients when mt-sDNA was positive.

CONCLUSIONS

In this real-world analysis of positive mt-sDNA referrals, adherence to subsequent diagnostic colonoscopy recommendations was high. The presence of pre-existing CRC risk factors did not affect the positive predictive value of mt-sDNA.

Surveillance colonoscopy findings in asymptomatic participants over 75 years of age

Background and Aim

Surveillance colonoscopy for colorectal cancer (CRC) is generally not recommended beyond 75 years of age. The study determined incidence and predictors of advanced adenoma and CRC in older individuals undergoing surveillance colonoscopy.

Methods

This was a retrospective cohort study of asymptomatic older participants (≥75 years), enrolled in a South Australian CRC surveillance program who underwent colonoscopy (2015-2020). Clinical records were extracted for demographics, personal or family history of CRC, comorbidities, polypharmacy, and colonoscopy findings. The associations between clinical variables and advanced adenoma or CRC at surveillance were assessed with multivariable Poisson regression analysis.

Results

Totally 698 surveillance colonoscopies were analyzed from 574 participants aged 75-91 years (55.6% male). The incidence of CRC was 1.6% (11/698), while 37.9% (260/698) of procedures had advanced adenoma detected. Previous CRC (incidence rate ratio [IRR] 5.9, 95% CI 1.5-22.5), age ≥85 years (IRR 5.8, 95% CI 1.6-20.1) and active smoking (IRR 4.9, 95% CI 1.0-24.4) were independently associated with CRC diagnosis, while advanced adenoma at immediately preceding colonoscopy (IRR 1.6, 95% CI 1.3-2.0) and polypharmacy (IRR 1.2, 95% CI 1.0-1.5) were associated with advanced adenoma at surveillance colonoscopy in asymptomatic older participants (≥75 years).

Conclusion

Advanced neoplasia was found in more than one third of the surveillance procedures completed in this cohort. Continuation of surveillance beyond age 75 yeasrs may be considered in participants who have previous CRC or are active smokers (provided they are fit to undergo colonoscopy). In other cases, such as past advanced adenoma only, the need for ongoing surveillance should be considered alongside participant preference and health status.

Colon Polyp Surveillance: Separating the Wheat From the Chaff

One goal of colorectal cancer (CRC) screening is to prevent CRC incidence by removing precancerous colonic polyps, which are detected in up to 50% of screening examinations. Yet, the lifetime risk of CRC is 3.9%-4.3%, so it is clear that most of these individuals with polyps would not develop CRC in their lifetime. It is, therefore, a challenge to determine which individuals with polyps will benefit from follow-up, and at what intervals. There is some evidence that individuals with advanced polyps, based on size and histology, benefit from intensive surveillance. However, a large proportion of individuals will have small polyps without advanced histologic features (ie, "nonadvanced"), where the benefits of surveillance are uncertain and controversial. Demand for surveillance will further increase as more polyps are detected due to increased screening uptake, recent United States recommendations to expand screening to younger individuals, and emergence of polyp detection technology. We review the current understanding and clinical implications of the natural history, biology, and outcomes associated with various categories of colon polyps based on size, histology, and number. Our aims are to highlight key knowledge gaps, specifically focusing on certain categories of polyps that may not be associated with future CRC risk, and to provide insights to inform research priorities and potential management strategies. Optimization of CRC prevention programs based on updated knowledge about the future risks associated with various colon polyps is essential to ensure cost-effective screening and surveillance, wise use of resources, and inform efforts to personalize recommendations.

Reducing the Risk of Delayed Colorectal Cancer Diagnoses Through an Ambulatory Safety Net Collaborative

BACKGROUND

An estimated 12 million adults in the United States experience delayed diagnoses and other diagnostic errors annually. Ambulatory safety nets (ASNs) are an intervention to reduce delayed diagnoses by identifying patients with abnormal results overdue for follow-up using registries, workflow redesign, and patient navigation. The authors sought to co-design a collaborative and implement colorectal cancer (CRC) ASNs across various health care settings.

METHODS

A working group was convened to co-design implementation guidance, measures, and the collaborative model. Collaborative sites were recruited through a medical professional liability insurance program and chose to begin with developing an ASN for positive at-home CRC screening or overdue surveillance colonoscopy. The 18-month Breakthrough Series Collaborative ran from January 2022 to July 2023, with sites continuing to collect data while sustaining their ASNs. Data were collected from sites monthly on patients in the ASN, including the proportion that was successfully contacted, scheduled, and completed a follow-up colonoscopy.

RESULTS

Six sites participated; four had an operational ASN at the end of the Breakthrough Series, with the remaining sites launching three months later. From October 2022 through February 2024, the Collaborative ASNs collectively identified 5,165 patients from the registry as needing outreach. Among patients needing outreach, 3,555 (68.8%) were successfully contacted, 2,060 (39.9%) were scheduled for a colonoscopy, and 1,504 (29.1%) completed their colonoscopy.

CONCLUSION

The Collaborative successfully identified patients with previously abnormal CRC screening and facilitated completion of follow-up testing. The CRC ASN Implementation Guide offers a comprehensive road map for health care leaders interested in implementing CRC ASNs.

Real-world data evaluating Guy's rapid diagnostic clinic as an alternate pathway for patients with FIT levels below 10

OBJECTIVE

To analyse the effectiveness of rapid diagnostic clinics (RDCs) as an alternative pathway for patients with concerning symptoms and a faecal immunochemical test (FIT) result <10. Our primary endpoint was rate of colorectal cancer (CRC) detection. Second endpoints were rates of other cancers and gastrointestinal (GI) serious benign conditions. Finally, we analysed the specific pathway followed by FIT <10 patients with cancer at Guy's and St Thomas NHS Foundation Trust (GSTT) RDC.

DESIGN

A retrospective and prospective cohort study.

SETTING

GSTT RDC, one of England's largest single-centre RDCs. Sociodemographic and clinical characteristics of FIT <10 patients were analysed descriptively.

PARTICIPANTS

Patients with an FIT result <10, seen at GSTT RDC between 1 January 2020 and 5 May 2023.

RESULTS

A total of 1299 patients with an FIT<10 were seen at GSTT RDC between January 2020 and May 2023. Of these, 66% (n=861) reported weight loss, 62% (n=805) pain, 37% (n=481) fatigue, 34% (n=444) were anaemic and 23% (n=301) had nausea and vomiting. Among these patients, 7% (n=88) received a cancer diagnosis, 36% (n=462) were identified as having a serious benign condition. Within the patients with cancer, 9% (n=8) were diagnosed with CRC. Among patients with serious benign conditions, 7% (n=31) were referred to colorectal, hepatopancreatobiliary, or upper GI specialists.

CONCLUSION

This study demonstrates the effectiveness of RDCs as an alternate pathway for FIT <10 patients with ongoing clinical concerns. These results contribute to enhancing patient care and optimising resource allocation within the healthcare system.

A Preclinical Blinded Randomized-Controlled Trial Evaluating the Clinical Relevance of Polyp Size Measurement Using a Virtual Scale Endoscope

Background

The virtual scale endoscope (VSE) helps endoscopists measure colorectal polyp size more accurately compared to visual assessment (VA). However, previous studies were not adequately powered to evaluate the sizing of polyps at clinically relevant size thresholds and relative accuracy for size subgroups.

Methods

We created 64 artificial polyps of varied sizes and Paris class morphology, randomly assigned 1:1 to be measured (383 total measurement datapoints with VSE and VA by 6 endoscopists blinded to true size) in a colon model. We added data from two previous trials (480 measurement datapoints). We evaluated for correct classification of polyps into size groups at 3 mm, 5 mm, 10 mm, and 20 mm size thresholds and the relative size measurement accuracy for diminutive polyps (≤5 mm), small polyps (5-9 mm), large polyps at 10-19 mm, and polyps (≥20).

Results

VSE had significantly less size group misclassifications at the 5 mm, and 10 mm thresholds (28 percent vs. 45 percent, P = 0.0159 and 26 percent vs. 44 percent, P = 0.0135, respectively). For the 3 mm and 20 mm thresholds, VSE had lower misclassifications; however, this was not statistically significant (36 percent vs. 46 percent, P = 0.3853 and 38 percent vs. 41 percent, P = 0.2705, respectively). The relative size measurement accuracy was significantly higher for VSE compared to VA for all size subgroups (diminutive (P < 0.01), small polyps (P < 0.01), 10-19 mm (P < 0.01), and ≥20 mm (P < 0.01)).

Conclusion

VSE outperforms VA in categorizing polyps into size groups at the clinically relevant size thresholds of 5 mm and 10 mm. Using VSE resulted in significantly higher relative measurement accuracy for all size subgroups.

A survey of current practices in post-polypectomy surveillance in Korea

BACKGROUND/AIMS

We investigated the clinical practice patterns of post-polypectomy colonoscopic surveillance among Korean endoscopists.

METHODS

In a web-based survey conducted between September and November 2021, participants were asked about their preferred surveillance intervals and the patient age at which surveillance was discontinued. Adherence to the recent guidelines of the U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) was also analyzed.

RESULTS

In total, 196 endoscopists completed the survey. The most preferred first surveillance intervals were: a 5-year interval after the removal of 1-2 tubular adenomas < 10 mm; a 3-year interval after the removal of 3-10 tubular adenomas < 10 mm, adenomas ≥ 10 mm, tubulovillous or villous adenomas, ≤ 20 hyperplastic polyps < 10 mm, 1-4 sessile serrated lesions (SSLs) < 10 mm, hyperplastic polyps or SSLs ≥ 10 mm, and traditional serrated adenomas; and a 1-year interval after the removal of adenomas with highgrade dysplasia, >10 adenomas, 5-10 SSLs, and SSLs with dysplasia. In piecemeal resections of large polyps ( > 20 mm), surveillance colonoscopy was mostly preferred after 1 year for adenomas and 6 months for SSLs. The mean USMSTF guideline adherence rate was 30.7%. The largest proportion of respondents (40.8%-55.1%) discontinued the surveillance at the patient age of 80-84 years.

CONCLUSIONS

A significant discrepancy was observed between the preferred post-polypectomy surveillance intervals and recent international guidelines. Individualized measures are required to increase adherence to the guidelines.

Single Versus Second Observer vs Artificial Intelligence to Increase the ADENOMA Detection Rate of Colonoscopy-A Network Analysis

BACKGROUND AND AIMS

Screening colonoscopy has significantly contributed to the reduction of the incidence of colorectal cancer (CRC) and its associated mortality, with adenoma detection rate (ADR) as the quality marker. To increase the ADR, various solutions have been proposed including the utilization of Artificial Intelligence (AI) and employing second observers during colonoscopies. In the interest of AI improving ADR independently, without a second observer, and the operational similarity between AI and second observer, this network meta-analysis aims at evaluating the effectiveness of AI, second observer, and a single observer in improving ADR.

METHODS

We searched the Medline, Embase, Cochrane, Web of Science Core Collection, Korean Citation Index, SciELO, Global Index Medicus, and Cochrane. A direct head-to-head comparator analysis and network meta-analysis were performed using the random-effects model. The odds ratio (OR) was calculated with a 95% confidence interval (CI) and p-value < 0.05 was considered statistically significant.

RESULTS

We analyzed 26 studies, involving 22,560 subjects. In the direct comparative analysis, AI demonstrated higher ADR (OR: 0.668, 95% CI 0.595-0.749, p < 0.001) than single observer. Dual observer demonstrated a higher ADR (OR: 0.771, 95% CI 0.688-0.865, p < 0.001) than single operator. In network meta-analysis, results were consistent on the network meta-analysis, maintaining consistency. No statistical difference was noted when comparing AI to second observer. (RR 1.1 (0.9-1.2, p = 0.3). Results were consistent when evaluating only RCTs. Net ranking provided higher score to AI followed by second observer followed by single observer.

CONCLUSION

Artificial Intelligence and second-observer colonoscopy showed superior success in Adenoma Detection Rate when compared to single-observer colonoscopy. Although not statistically significant, net ranking model favors the superiority of AI to the second observer.

Social determinants of health influencing the adherence to post-endoscopic mucosal resection surveillance

BACKGROUND AND AIMS

Colorectal cancer (CRC) is a global health challenge, particularly in Alabama, where the incidence rates exceed national averages. This study investigated the factors influencing adherence to post-endoscopic mucosal resection (EMR) colonoscopies, focusing on travel distance and socioeconomic status. This study aimed to provide evidence-based insights to improve patient care in CRC management.

METHODS

This retrospective study in a tertiary care referral center analyzed 465 patients who underwent EMR. The data included demographics, clinical details, and travel-related variables. Descriptive statistics, logistic regression, and spatial analysis were used to assess the factors affecting adherence.

RESULTS

Of 465 patients, 36.6 % had adequate follow-up, 21.8 % had inadequate follow-up, and 41.6 % were lost to follow-up. Noteworthy demographic variations were observed, with median ages differing across adherence groups. Traveled distances showcased compelling insights, indicating a median distance of 22.2 miles for adequate follow-up, 15.7 miles for inadequate follow-up, and 31.6 miles for the lost-to-follow-up group (p<0.001). Longer travel distances were associated with better adherence. Longer travel distances from the hospital were associated with significantly lower odds of inadequate follow-up: 10-25 miles OR:0.29, 25-85 miles OR:0.35, and >80 miles OR:0.24 compared to the first quartile (<10 miles). Socioeconomic factors, particularly educational attainment, significantly influenced the follow-up rates.

CONCLUSIONS

This study revealed suboptimal post-EMR follow-up rates and underscored the impact of travel distance and socioeconomic factors. Targeted interventions addressing distance-related barriers can enhance treatment adherence and ensure timely CRC surveillance after EMR. Further research is needed in diverse healthcare settings.

Audit of hemostatic clip use after colorectal polyp resection in an academic endoscopy unit

Background and study aims Prophylactic closure of endoscopic resection defects reduces delayed hemorrhage after resection of non-pedunculated colorectal lesions ≥ 20 mm that are located proximal to the splenic flexure and removed by electrocautery. The risk of delayed hemorrhage after cold (without electrocautery) resection is much lower, and prophylactic clip closure after cold resection is generally unnecessary. The aim of this study was to audit clip use after colorectal polyp resection in routine outpatient colonoscopies at two outpatient centers within an academic medical center. Patients referred for resection of known lesions were excluded. Patients and methods Retrospective chart analysis was performed as part of a quality review of physician adherence to screening and post-polypectomy surveillance intervals. Results Among 3784 total lesions resected cold by 29 physicians, clips were placed after cold resection on 41.7% of 12 lesions ≥ 20 mm, 19.3% of 207 lesions 10 to 19 mm in size, and 2.8% of 3565 lesions 1 to 9 mm in size. Three physicians placed clips after cold resection of lesions 1 to 9 mm in 18.8%, 25.5%, and 45.0% of cases. These physicians accounted for 8.1% of 1- to 9-mm resections, but 69.7% of clips placed in this size range. Electrocautery was used for 3.1% of all resections. Clip placement overall after cold resection (3.9%) was much lower than after resection with electrocautery (71.1%), but 62.4% of all clips placed were after cold resection. Conclusions Audits of clip use in an endoscopy practice can reveal surprising findings, including high and variable rates of unnecessary use after cold resection. Audit can potentially reduce unnecessary costs, carbon emissions, and plastic waste.

Effectiveness and Cost-Effectiveness of Colorectal Cancer Screening With a Blood Test That Meets the Centers for Medicare & Medicaid Services Coverage Decision

BACKGROUND & AIMS

A blood-based colorectal cancer (CRC) screening test may increase screening participation. However, blood tests may be less effective than current guideline-endorsed options. The Centers for Medicare & Medicaid Services (CMS) covers blood tests with sensitivity of at least 74% for detection of CRC and specificity of at least 90%. In this study, we investigate whether a blood test that meets these criteria is cost-effective.

METHODS

Three microsimulation models for CRC (MISCAN-Colon, CRC-SPIN, and SimCRC) were used to estimate the effectiveness and cost-effectiveness of triennial blood-based screening (from ages 45 to 75 years) compared to no screening, annual fecal immunochemical testing (FIT), triennial stool DNA testing combined with an FIT assay, and colonoscopy screening every 10 years. The CMS coverage criteria were used as performance characteristics of the hypothetical blood test. We varied screening ages, test performance characteristics, and screening uptake in a sensitivity analysis.

RESULTS

Without screening, the models predicted 77-88 CRC cases and 32-36 CRC deaths per 1000 individuals, costing $5.3-$5.8 million. Compared to no screening, blood-based screening was cost-effective, with an additional cost of $25,600-$43,700 per quality-adjusted life-year gained (QALYG). However, compared to FIT, triennial stool DNA testing combined with FIT, and colonoscopy, blood-based screening was not cost-effective, with both a decrease in QALYG and an increase in costs. FIT remained more effective (+5-24 QALYG) and less costly (-$3.2 to -$3.5 million) than blood-based screening even when uptake of blood-based screening was 20 percentage points higher than uptake of FIT.

CONCLUSION

Even with higher screening uptake, triennial blood-based screening, with the CMS-specified minimum performance sensitivity of 74% and specificity of 90%, was not projected to be cost-effective compared with established strategies for colorectal cancer screening.

A colonial serrated polyp classification model using white-light ordinary endoscopy images with an artificial intelligence model and TensorFlow chart

In this study, we implemented a combination of data augmentation and artificial intelligence (AI) model-Convolutional Neural Network (CNN)-to help physicians classify colonic polyps into traditional adenoma (TA), sessile serrated adenoma (SSA), and hyperplastic polyp (HP). We collected ordinary endoscopy images under both white and NBI lights. Under white light, we collected 257 images of HP, 423 images of SSA, and 60 images of TA. Under NBI light, were collected 238 images of HP, 284 images of SSA, and 71 images of TA. We implemented the CNN-based artificial intelligence model, Inception V4, to build a classification model for the types of colon polyps. Our final AI classification model with data augmentation process is constructed only with white light images. Our classification prediction accuracy of colon polyp type is 94%, and the discriminability of the model (area under the curve) was 98%. Thus, we can conclude that our model can help physicians distinguish between TA, SSA, and HPs and correctly identify precancerous lesions such as TA and SSA.

Genome-wide polygenic risk scores for colorectal cancer have implications for risk-based screening

BACKGROUND

Hereditary factors, including single genetic variants and family history, can be used for targeting colorectal cancer (CRC) screening, but limited data exist on the impact of polygenic risk scores (PRS) on risk-based CRC screening.

METHODS

Using longitudinal health and genomics data on 453,733 Finnish individuals including 8801 CRC cases, we estimated the impact of a genome-wide CRC PRS on CRC screening initiation age through population-calibrated incidence estimation over the life course in men and women.

RESULTS

Compared to the cumulative incidence of CRC at age 60 in Finland (the current age for starting screening in Finland), a comparable cumulative incidence was reached 5 and 11 years earlier in persons with high PRS (80-99% and >99%, respectively), while those with a low PRS (< 20%) reached comparable incidence 7 years later. The PRS was associated with increased risk of post-colonoscopy CRC after negative colonoscopy (hazard ratio 1.76 per PRS SD, 95% CI 1.54-2.01). Moreover, the PRS predicted colorectal adenoma incidence and improved incident CRC risk prediction over non-genetic risk factors.

CONCLUSIONS

Our findings demonstrate that a CRC PRS can be used for risk stratification of CRC, with further research needed to optimally integrate the PRS into risk-based screening.

Optimizing Timing of Follow-Up Colonoscopy: A Pilot Cluster Randomized Trial of a Knowledge Translation Tool

BACKGROUND

Endoscopists have low adherence to guideline-recommended colonoscopy surveillance intervals. We performed a cluster-randomized single-blind pilot trial in Winnipeg, Canada, to assess the effectiveness of a newly developed digital application tool that computes guideline-recommended follow-up intervals.

METHODS

Participant endoscopists were randomized to either receive access to the digital application (intervention group) or not receive access (control group). Pathology reports and final recommendations for colonoscopies performed in the 1-4 months before randomization and 3-7 months postrandomization were extracted. Generalized estimating equation models were used to determine whether the access to the digital application predicted guideline congruence.

RESULTS

We included 15 endoscopists in the intervention group and 14 in the control group (of 42 eligible endoscopists in the city), with 343 patients undergoing colonoscopy before randomization and 311 postrandomization. Endoscopists who received the application made guideline-congruent recommendations 67.6% of the time before randomization and 76.1% of the time after randomization. Endoscopists in the control group made guideline-congruent recommendations 72.4% and 72.9% of the time before and after randomization, respectively. Endoscopists in the intervention group trended to have an increase in guideline adherence comparing postintervention with preintervention (odds ratio [OR]: 1.50, 95% confidence interval [CI] 0.82-2.74). By contrast, the control group had no change in guideline adherence (OR: 1.07, 95% CI 0.50-2.29). Endoscopists in the intervention group with less than median guideline congruence prerandomization had a significant increase in guideline-congruent recommendations postrandomization.

DISCUSSION

An application that provides colonoscopy surveillance intervals may help endoscopists with guideline congruence, especially those with a lower preintervention congruence with guideline recommendations ( ClincialTrials.gov number, NCT04889352).

Impact of computer-aided characterization for diagnosis of colorectal lesions, including sessile serrated lesions: Multireader, multicase study

OBJECTIVES

Computer-aided characterization (CADx) may be used to implement optical biopsy strategies into colonoscopy practice; however, its impact on endoscopic diagnosis remains unknown. We aimed to evaluate the additional diagnostic value of CADx when used by endoscopists for assessing colorectal polyps.

METHODS

This was a single-center, multicase, multireader, image-reading study using randomly extracted images of pathologically confirmed polyps resected between July 2021 and January 2022. Approved CADx that could predict two-tier classification (neoplastic or nonneoplastic) by analyzing narrow-band images of the polyps was used to obtain a CADx diagnosis. Participating endoscopists determined if the polyps were neoplastic or not and noted their confidence level using a computer-based, image-reading test. The test was conducted twice with a 4-week interval: the first test was conducted without CADx prediction and the second test with CADx prediction. Diagnostic performances for neoplasms were calculated using the pathological diagnosis as reference and performances with and without CADx prediction were compared.

RESULTS

Five hundred polyps were randomly extracted from 385 patients and diagnosed by 14 endoscopists (including seven experts). The sensitivity for neoplasia was significantly improved by referring to CADx (89.4% vs. 95.6%). CADx also had incremental effects on the negative predictive value (69.3% vs. 84.3%), overall accuracy (87.2% vs. 91.8%), and high-confidence diagnosis rate (77.4% vs. 85.8%). However, there was no significant difference in specificity (80.1% vs. 78.9%).

CONCLUSIONS

Computer-aided characterization has added diagnostic value for differentiating colorectal neoplasms and may improve the high-confidence diagnosis rate.

Estimate of Increase in Colorectal Cancer Diagnoses with Expansion of Fecal Immunochemical Testing in an Urban Safety-Net Population

BACKGROUND

Fecal immunochemical test (FIT) is less effective in detecting advanced adenomas (AA) than colonoscopy. Increase in FIT for colorectal cancer (CRC) screening may lead to an increased number of undetected AAs which may develop into future CRCs.

AIM

We determined the potential impact of FIT expansion on missed AAs and future CRC diagnoses in an urban, tertiary-care, safety-net hospital.

METHODS

CRC and AA diagnoses were identified in patients undergoing colonoscopy for average-risk CRC screening or positive FIT between 2017 and 2019 at Boston Medical Center. Poisson regression modeling was used to estimate the frequency of AAs per year by age group using data from 2017 to 2019, assuming average outpatient volume and proportion of screening colonoscopies. Total number of patients who received FIT was extrapolated from those who underwent colonoscopy for positive FIT. We estimated AAs per year if 'one-time' FIT was used for screening in 75% and 100% of the population and subtracted this from the estimated AAs per year under the Poisson model to determine missed AAs. We used previously described, age and gender specific estimates of the annual progression of AA to CRC.

RESULTS

The estimated number of CRCs detected per year is 4.6/1785 males and 4.6/2086 females screened. With 75% FIT expansion, we estimate an additional 3.5 (95% CI 1.3, 9.5) and 2.2 (95% CI 0.64, 7.6) CRCs; with 100% FIT expansion, we estimate an additional 7.4 (95% CI 3.7, 14.9) and 4.2 (95% CI 1.7, 10.5) CRCs, in 5 years, in males and females, respectively.

CONCLUSION

Expansion of FIT may substantially increase CRC incidence.

Assessing Guidelines on the Need for Colonoscopy After Initial Flexible Sigmoidoscopy in Young Patients With Outlet-Type Rectal Bleeding

BACKGROUND

Although young-age-of-onset colorectal cancer is increasing in incidence, lack of screening leads to symptomatic presentation, often with rectal bleeding. Because most cancers in patients younger than 50 years are left-sided, flexible sigmoidoscopy is a reasonable way of investigating bleeding in these patients.

OBJECTIVE

To predict which patients undergoing flexible sigmoidoscopy for outlet-type rectal bleeding need a full colonoscopy.

DESIGN

Findings at colonoscopy were compared with published indications for colonoscopy after flexible sigmoidoscopy, which were as follows: 1) any number of advanced adenomas defined as a tubular adenoma of >9 mm diameter, a tubulovillous or villous adenoma of any size, or any adenoma with high-grade dysplasia; 2) 3 or more tubular adenomas of any size or histology; 3) any sessile serrated lesion; and 4) 20 or more hyperplastic polyps.

SETTING

Charity Hospital with volunteer specialists.

PATIENTS

Patients were included if they were younger than 57 years, had outlet-type rectal bleeding, and underwent flexible sigmoidoscopy at least to the descending colon followed by colonoscopy with biopsy of all resected lesions.

INTERVENTIONS

Flexible sigmoidoscopy and colonoscopy with excision of all removable lesions.

MAIN OUTCOME MEASURES

Findings at colonoscopy.

RESULTS

There were 66 patients who had a colonoscopy between 5 and 811 days after sigmoidoscopy and also had complete data. There were 43 men and 23 women with a mean age of 39.5 years. Analysis of flexible sigmoidoscopy criteria for finding proximal high-risk lesions on colonoscopy showed a sensitivity of 76.9%, a specificity of 67.9%, a positive predictive value of 37%, a negative predictive value of 92.3%, and an accuracy of 69.7%.

LIMITATIONS

A large number of exclusions for inadequate colonoscopy or inadequate data resulted in a reduced patient number in the study.

CONCLUSIONS

Our criteria for follow-up colonoscopy based on the findings at initial flexible sigmoidoscopy in young patients with outlet-type rectal bleeding are reliable enough to be used in routine clinical practice, provided this is audited. See Video Abstract.

GUA DE EVALUACIN PARA LA NECESIDAD DE COLONOSCOPIA DESPUS DE UNA SIGMOIDOSCOPIA FLEXIBLE INICIAL EN PACIENTES JVENES CON RECTORRAGIA

ANTECEDENTES:Si bien la edad de aparición temprana del cáncer colorrectal está aumentando en incidencia, la falta de pruebas de detección conduce a una presentación sintomática, a menudo con sangrado rectal. Debido a que la mayoría de los cánceres en pacientes menores de 50 años son del lado izquierdo, la sigmoidoscopia flexible es una forma razonable de investigar el sangrado en estos pacientes.OBJETIVO:Predecir qué pacientes sometidos a sigmoidoscopia flexible por rectorragia necesitan una colonoscopia completa.DISEÑO:Los resultados de la colonoscopia se compararon con las indicaciones publicadas para la colonoscopia después de una sigmoidoscopia flexible. Estos fueron: 1. Cualquier número de adenomas avanzados, definidos como un adenoma tubular > 9 mm, un adenoma tubulovelloso o velloso de cualquier tamaño, o cualquier adenoma con displasia de alto grado. 2. Tres o más adenomas tubulares de cualquier tamaño o histología. 3. Cualquier lesión serrada sésil. 4. Veinte o más pólipos hiperplásicos.ENTORNO CLINICO:Hospital de Caridad con especialistas voluntarios.PACIENTES:Menores de 57 años, con rectorragia, sometidos a sigmoidoscopia flexible al menos hasta el colon descendente, seguida de colonoscopia con biopsia de todas las lesiones resecadas.INTERVENCIONES:sigmoidoscopia flexible y colonoscopia con escisión de todas las lesiones removibles.PRINCIPALES MEDIDAS DE VALORACIÓN:Hallazgos en la colonoscopia.RESULTADOS:66 casos a los que se les realizó una colonoscopia entre 5 y 811 días después de la sigmoidoscopia, que también tenían datos completos. 43 hombres y 23 mujeres con una edad media de 39,5 años. El análisis de los criterios de sigmoidoscopia flexible para encontrar lesiones proximales de alto riesgo en la colonoscopia mostró una sensibilidad del 76,9 %, una especificidad del 67,9 %, un valor predictivo positivo del 37 %, un valor predictivo negativo del 92,3 % y una precisión del 69,7 %.LIMITACIONES:Gran número de exclusiones por colonoscopia inadecuada o datos inadecuados que causan un número reducido de pacientes en el estudio.CONCLUSIÓN:Nuestros criterios para la colonoscopia de seguimiento basados en los hallazgos de la sigmoidoscopia flexible inicial en pacientes jóvenes con rectorragia son lo suficientemente confiables para ser utilizados en la práctica clínica habitual, siempre que se audite. (Traducción- Dr. Ingrid Melo ).

The Clinical Impact and Cost-Effectiveness of Surveillance of Incidentally Detected Gastric Intestinal Metaplasia: A Microsimulation Analysis

BACKGROUND & AIMS

Gastric intestinal metaplasia (GIM) is associated with a higher risk of noncardia intestinal gastric adenocarcinoma (GA). The aim of this study was to estimate lifetime benefits, complications, and cost-effectiveness of GIM surveillance using esophagogastroduodenoscopy (EGD).

METHODS

We developed a semi-Markov microsimulation model of patients with incidentally detected GIM, to compare the effectiveness of EGD surveillance with no surveillance at 10-year, 5-year, 3-year, 2-year, and 1-year intervals. We modeled a simulated cohort of 1,000,000 US individuals aged 50 with incidental GIM. Outcome measures were lifetime GA incidence, mortality, number of EGDs, complications, undiscounted life-years gained, and incremental cost-effectiveness ratio with a willingness-to-pay threshold of $100,000/quality-adjusted life-year (QALY).

RESULTS

In the absence of surveillance, the model simulated 32.0 lifetime GA cases and 23.0 lifetime GA deaths per 1000 individuals with GIM, respectively. Among surveilled individuals, simulated lifetime GA incidence (per 1000) decreased with shorter surveillance intervals (10-year to 1-year, 11.2-6.1) as did GA mortality (7.4-3.6). Compared with no surveillance, all modeled surveillance intervals yielded greater life expectancy (87-190 undiscounted life-years gained per 1000); 5-year surveillance provided the greatest number of life-years gained per EGD performed and was the cost-effective strategy ($40,706/QALY). In individuals with risk factors of family history of GA or anatomically extensive, incomplete-type GIM intensified 3-year surveillance was cost-effective (incremental cost-effectiveness ratio $28,156/QALY and $87,020/QALY, respectively).

CONCLUSIONS

Using microsimulation modeling, surveillance of incidentally detected GIM every 5 years is associated with reduced GA incidence/mortality and is cost-effective from a health care sector perspective. Real-world studies evaluating the impact of GIM surveillance on GA incidence and mortality in the United States are needed.

Direct comparison of multiple computer-aided polyp detection systems

BACKGROUND AND STUDY AIMS

 Artificial intelligence (AI)-based systems for computer-aided detection (CADe) of polyps receive regular updates and occasionally offer customizable detection thresholds, both of which impact their performance, but little is known about these effects. This study aimed to compare the performance of different CADe systems on the same benchmark dataset.

METHODS

 101 colonoscopy videos were used as benchmark. Each video frame with a visible polyp was manually annotated with bounding boxes, resulting in 129 705 polyp images. The videos were then analyzed by three different CADe systems, representing five conditions: two versions of GI Genius, Endo-AID with detection Types A and B, and EndoMind, a freely available system. Evaluation included an analysis of sensitivity and false-positive rate, among other metrics.

RESULTS

 Endo-AID detection Type A, the earlier version of GI Genius, and EndoMind detected all 93 polyps. Both the later version of GI Genius and Endo-AID Type B missed 1 polyp. The mean per-frame sensitivities were 50.63 % and 67.85 %, respectively, for the earlier and later versions of GI Genius, 65.60 % and 52.95 %, respectively, for Endo-AID Types A and B, and 60.22 % for EndoMind.

CONCLUSIONS

 This study compares the performance of different CADe systems, different updates, and different configuration modes. This might help clinicians to select the most appropriate system for their specific needs.

What are the priority quality indicators for colonoscopy in real-world clinical practice?

Colonoscopy is widely used as a colorectal cancer (CRC) screening tool. The effectiveness of a screening colonoscopy is associated with a decreased risk of CRC. However, colonoscopy is an operator-dependent procedure, and endoscopists' quality performance varies widely. This article reviewed the priority metrics and practices that contribute to high-quality screening colonoscopy in real-world clinical practice. With growing evidence, quality indicators have been subject to intense research and associated with reducing postcolonoscopy CRC incidence and mortality. Some quality metrics can reflect an endoscopy unit-based practice (i.e. quality of bowel preparation and withdrawal time). Other quality indicators primarily reflect individuals' skill and knowledge (i.e. cecal intubation rate, adenoma detection rate, and appropriately assigned follow-up colonoscopy interval). Measurement and improvement of priority quality indicators for colonoscopy should be made at both the endoscopist and unit levels. Substantial evidence supports the impact of high-quality colonoscopy in reducing the incidence of postcolonoscopy CRC.

Low delayed bleeding and high complete closure rate of mucosal defects with the novel through-the-scope dual-action tissue clip after endoscopic resection of large nonpedunculated colorectal lesions (with video)

BACKGROUND AND AIMS

Complete closure after endoscopic resection of large nonpedunculated colorectal lesions (LNPCLs) can reduce delayed bleeding but is challenging with conventional through-the-scope (TTS) clips alone. The novel dual-action tissue (DAT) clip has clip arms that open and close independently of each other, facilitating tissue approximation. We aimed to evaluate the rate of complete closure and delayed bleeding with the DAT clip after endoscopic resection of LNPCLs.

METHODS

This was a multicenter prospective cohort study of all patients who underwent defect closure with the DAT clip after EMR or endoscopic submucosal dissection (ESD) of LNPCLs ≥20 mm from July 2022 to May 2023. Delayed bleeding was defined as a bleeding event requiring hospitalization, blood transfusion, or any intervention within 30 days after the procedure. Complete closure was defined as apposition of mucosal defect margins without visible submucosal areas <3 mm along the closure line.

RESULTS

One hundred seven patients (median age, 64 years; 42.5% women) underwent EMR (n = 63) or ESD (n = 44) of LNPCLs (median size, 40 mm; 74.8% right-sided colon) followed by defect closure. Complete closure was achieved in 96.3% (n = 103) with a mean of 1.4 ± .6 DAT clips and 2.9 ± 1.8 TTS clips. Delayed bleeding occurred in 1 patient (.9%) without requiring additional interventions.

CONCLUSIONS

The use of the DAT clip in conjunction with TTS clips achieved high complete defect closure after endoscopic resection of large LNPCLs and was associated with a .9% delayed bleeding rate. Future comparative trials and formal cost-analyses are needed to validate these findings. (Clinical trial registration number: NCT05852457.).

Tata Memorial Centre Evidence Based Management of Colorectal cancer

ABSTRACT

This review article examines the evidence-based management of colorectal cancers, focusing on topics characterized by ongoing debates and evolving evidence. To contribute to the scientific discourse, we intentionally exclude subjects with established guidelines, concentrating instead on areas where the current understanding is dynamic. Our analysis encompasses a thorough exploration of critical themes, including the evidence surrounding complete mesocolic excision and D3 lymphadenectomy in colon cancers. Additionally, we delve into the evolving landscape of perioperative chemotherapy in both colon and rectal cancers, considering its nuanced role in the context of contemporary treatment strategies. Advancements in surgical techniques are a pivotal aspect of our discussion, with an emphasis on the utilization of minimally invasive approaches such as laparoscopy and robotic surgery in both colon and rectal cancers, including advanced rectal cases. Moving beyond conventional radical procedures, we scrutinize the feasibility and implications of endoscopic resections for small tumors, explore the paradigm of organ preservation in locally advanced rectal cancers, and assess the utility of total neoadjuvant therapy in the current treatment landscape. Our final segment reviews pivotal trials that have significantly influenced the management of colorectal liver and peritoneal metastasis.

Colon polyps: updates in classification and management

PURPOSE OF REVIEW

Colon polyps are potential precursors to colorectal cancer (CRC), which remains one of the most common causes of cancer-associated death. The proper identification and management of these colorectal polyps is an important quality measure for colonoscopy outcomes. Here, we review colon polyp epidemiology, their natural history, and updates in endoscopic classification and management.

RECENT FINDINGS

Colon polyps that form from not only the adenoma, but also the serrated polyp pathway have significant risk for future progression to CRC. Therefore, correct identification and management of sessile serrated lesions can improve the quality of screening colonoscopy. Malignant polyp recognition continues to be heavily reliant on well established endoscopic classification systems and plays an important role in intraprocedural management decisions. Hot snare remains the gold standard for pedunculated polyp resection. Nonpedunculated noninvasive lesions can be effectively removed by large forceps if diminutive, but cold snare is preferred for colon polyps 3-20 mm in diameter. Larger lesions at least 20 mm require endoscopic mucosal resection. Polyps with the endoscopic appearance of submucosal invasion require surgical referral or advanced endoscopic resection in select cases. Advances in artificial intelligence may revolutionize endoscopic polyp classification and improve both patient and cost-related outcomes of colonoscopy.

SUMMARY

Clinicians should be aware of the most recent updates in colon polyp classification and management to provide the best care to their patients initiating screening colonoscopy.

Evaluation of computer aided detection during colonoscopy among Veterans: Randomized clinical trial

BACKGROUND

There has been significant interest in use of computer aided detection (CADe) devices in colonoscopy to improve polyp detection and reduce miss rate.

AIM

To investigate the use of CADe amongst veterans.

METHODS

Between September 2020 and December 2021, we performed a randomized controlled trial to evaluate the impact of CADe. Patients at Veterans Affairs Palo Alto Health Care System presenting for screening or low-risk surveillance were randomized to colonoscopy performed with or without CADe. Primary outcomes of interest included adenoma detection rate (ADR), adenomas per colonoscopy (APC), and adenomas per extraction. In addition, we measured serrated polyps per colonoscopy, non-adenomatous, non-serrated polyps per colonoscopy, serrated polyp detection rate, and procedural time.

RESULTS

A total of 244 patients were enrolled (124 with CADe), with similar patient characteristics (age, sex, body mass index, indication) between the two groups. Use of CADe was found to have decreased number of adenomas (1.79 vs 2.53, P = 0.030) per colonoscopy compared to without CADe. There was no significant difference in number of serrated polyps or non-adenomatous non-serrated polyps per colonoscopy between the two groups. Overall, use of CADe was found to have lower ADR (68.5% vs 80.0%, P = 0.041) compared to without use of CADe. Serrated polyp detection rate was lower with CADe (3.2% vs 7.5%) compared to without CADe, but this was not statistically significant (P = 0.137). There was no significant difference in withdrawal and procedure times between the two groups or in detection of adenomas per extraction (71.4% vs 73.1%, P = 0.613). No adverse events were identified.

CONCLUSION

While several randomized controlled trials have demonstrated improved ADR and APC with use of CADe, in this RCT performed at a center with high ADR, use of CADe was found to have decreased APC and ADR. Further studies are needed to understand the true impact of CADe on performance quality among endoscopists as well as determine criteria for endoscopists to consider when choosing to adopt CADe in their practices.

Age Matters: Adenoma Detection Rates in Average-risk Screening Patients Aged 45 to 49 Compared With Those Aged 50 to 54

GOALS

This study aims to address gaps in medical knowledge by determining whether adenoma detection rate (ADR) in average-risk screening patients aged 45 to 49 is equivalent to screening patients aged 50 to 54.

BACKGROUND

Current guidelines recommend initiating colon cancer screening at age 45, yet our understanding of the effects of ADR in average-risk individuals among 45- to 49-year-olds is still limited.

STUDY

A retrospective analysis was conducted on records of average-risk screening colonoscopies performed on patients aged 45 to 54 from January 2018 to August 2022. Exclusions were prior diagnoses of colorectal cancer or adenomatous polyps, inflammatory bowel disease, personal or family history of genetic cancer syndromes, incomplete colonoscopy, and inadequate bowel preparation. The primary outcome was ADR in the age 45 to 49 group compared with the age 50 to 54 group.

RESULTS

Of the 3199 average-risk screening colonoscopies performed, 879 and 2116 patients were included in the age 45 to 49 and 50 to 54 groups, respectively. Both groups were predominantly female, White ethnicity, never smokers, and obese. ADR was found to be 27% in the age 45 to 49 group compared with 34% in the age 50 to 54 group (odds ratio 0.70, 90% CI: 0.60-0.83, P-value for equivalence=0.81 w/ margin 0.77 to 1.30).

CONCLUSIONS

The study did not demonstrate equivalent ADR between the 2 age groups, with ADR being substantially lower in the age 45 to 49 group (27% vs. 34%). Despite this, the ADR in the 45 to 49 age range surpasses the established benchmark of 25%, supporting the decision to lower the screening age to 45 years. Ongoing national monitoring is essential to comprehensively evaluate the impact of these updated guidelines.

Risk-Stratified Screening for Colorectal Cancer Using Genetic and Environmental Risk Factors: A Cost-Effectiveness Analysis Based on Real-World Data

BACKGROUND & AIMS

Previous studies on the cost-effectiveness of personalized colorectal cancer (CRC) screening were based on hypothetical performance of CRC risk prediction and did not consider the association with competing causes of death. In this study, we estimated the cost-effectiveness of risk-stratified screening using real-world data for CRC risk and competing causes of death.

METHODS

Risk predictions for CRC and competing causes of death from a large community-based cohort were used to stratify individuals into risk groups. A microsimulation model was used to optimize colonoscopy screening for each risk group by varying the start age (40-60 years), end age (70-85 years), and screening interval (5-15 years). The outcomes included personalized screening ages and intervals and cost-effectiveness compared with uniform colonoscopy screening (ages 45-75, every 10 years). Key assumptions were varied in sensitivity analyses.

RESULTS

Risk-stratified screening resulted in substantially different screening recommendations, ranging from a one-time colonoscopy at age 60 for low-risk individuals to a colonoscopy every 5 years from ages 40 to 85 for high-risk individuals. Nevertheless, on a population level, risk-stratified screening would increase net quality-adjusted life years gained (QALYG) by only 0.7% at equal costs to uniform screening or reduce average costs by 1.2% for equal QALYG. The benefit of risk-stratified screening improved when it was assumed to increase participation or costs less per genetic test.

CONCLUSIONS

Personalized screening for CRC, accounting for competing causes of death risk, could result in highly tailored individual screening programs. However, average improvements across the population in QALYG and cost-effectiveness compared with uniform screening are small.

Risk of recurrent advanced colorectal neoplasia in individuals with baseline non-advanced neoplasia followed up at 5 vs 7-10 years

BACKGROUND AND AIM

Colorectal cancer (CRC) is one of the commonest cancers, especially among the Asian populations. We compared the recurrence rate of advanced colorectal neoplasia (ACN) at 5 year vs 7-10 years among individuals with non-advanced adenoma (NAA) detected and polypectomized at baseline colonoscopy in a large Chinese population.

METHODS

We extracted data of a large Chinese population with NAA polypectomized who received surveillance colonoscopy after 5 or 7-10 years from a large database (2008-2018). The outcome variable included recurrence of ACN at surveillance colonoscopy. We examined the association between length of surveillance and the outcome variable, whilst controlling for risk factors of colorectal cancer.

RESULTS

We include 109 768 subjects who have received a baseline colonoscopy from our dataset. They were aged 67.35 (SD 9.84) years, and 60.9% of them were male subjects. The crude 5-year and 10-year recurrence rate of ACN was 1.50% and 2.42%, respectively (crude odds ratio = 1.629, 95% CI 1.362 to 1.949, P < 0.001). From the binary logistic regression model, individuals with surveillance colonoscopy performed at 10 years had a statistically higher recurrence rate of ACN than those followed-up at 5 year (adjusted odds ratio [aOR] = 1.544, 95% CI 1.266 to 1.877, P < 0.001), but the effect size of aOR is small.

CONCLUSIONS

There is a small difference in recurrence of ACN between individuals who received colonoscopy workup at 5 years vs 7-10 years. These findings support a 7-10 years surveillance period after baseline NAA was polypectomized.

Representation of Racial Minorities in the United States Colonoscopy Surveillance Interval Guidelines

BACKGROUND/AIMS

Clinical guidelines should ideally be formulated from data representative of the population they are applicable to; however, historically, studies have disproportionally enrolled non-Hispanic White (NHW) patients, leading to potential inequities in care for minority groups. Our study aims to evaluate the extent to which racial minorities were represented in the United States Colorectal Cancer Surveillance Guidelines.

METHODS

We reviewed US guidelines between 1997 and 2020 and all identified studies cited by recommendations for surveillance after a baseline colonoscopy with no polyps, adenomas, sessile serrated polyps, and hyperplastic polyps. We analyzed the proportion of studies reporting race, and among these studies, we calculated the racial distribution of patients and compared the proportion of Non-NHW patients between each subtype.

RESULTS

For all guidelines, we reviewed 75 studies encompassing 9,309,955 patients. Race was reported in 24% of studies and 14% of total patients. Non-NHW comprised 43% of patients in studies for normal colonoscopies, compared with 9% for adenomas, 22% for sessile serrated polyps, and 15% for hyperplastic polyps. For the 2020 guidelines, we reviewed 33 studies encompassing 5,930,722 patients. Race was reported in 15% of studies and 21% of total patients. Non-NHW comprised 43% of patients in studies for normal colonoscopies, compared with 9% for tubular adenomas. Race was not cited for any other 2020 guideline.

CONCLUSION

Racial minorities are significantly underrepresented in US Colorectal Cancer Surveillance Guidelines, which may contribute to disparities in care. Future studies should prioritize enrolling a diverse patient population to provide data that accurately reflects their population.

Multitarget Stool RNA Test for Colorectal Cancer Screening

Importance

Noninvasive tests for colorectal cancer screening must include sensitive detection of colorectal cancer and precancerous lesions. These tests must be validated for the intended-use population, which includes average-risk individuals 45 years or older.

Objective

To evaluate the sensitivity and specificity of a noninvasive, multitarget stool RNA (mt-sRNA) test (ColoSense) test compared with results from a colonoscopy.

Design, Setting, and Participants

This phase 3 clinical trial (CRC-PREVENT) was a blinded, prospective, cross-sectional study to support a premarket approval application for a class III medical device. A total of 8920 participants were identified online using social media platforms and enrolled from June 2021 to June 2022 using a decentralized nurse call center. All participants completed the mt-sRNA test, which incorporated a commercially available fecal immunochemical test (FIT), concentration of 8 RNA transcripts, and participant-reported smoking status. Stool samples were collected prior to participants completing a colonoscopy at their local endoscopy center. The mt-sRNA test results (positive or negative) were compared with index lesions observed on colonoscopy. Over the course of 12 months, individuals 45 years and older were enrolled in the clinical trial using the decentralized recruitment strategy. Participants were enrolled from 49 US states and obtained colonoscopies at more than 3800 different endoscopy centers.

Main Outcomes and Measures

The primary outcomes included the sensitivity of the mt-sRNA test for detecting colorectal cancer and advanced adenomas and the specificity for no lesions on colonoscopy.

Results

The mean (range) age of participants was 55 (45-90) years, with 4% self-identified as Asian, 11% as Black, and 7% as Hispanic. Of the 8920 eligible participants, 36 (0.40%) had colorectal cancer and 606 (6.8%) had advanced adenomas. The mt-sRNA test sensitivity for detecting colorectal cancer was 94%, sensitivity for detecting advanced adenomas was 46%, and specificity for no lesions on colonoscopy was 88%. The mt-sRNA test showed significant improvement in sensitivity for colorectal cancer (94% vs 78%; McNemar P = .01) and advanced adenomas (46% vs 29%; McNemar P < .001) compared with results of the FIT.

Conclusions and Relevance

In individuals 45 years and older, the mt-sRNA test showed high sensitivity for colorectal neoplasia (colorectal cancer and advanced adenoma) with significant improvement in sensitivity relative to the FIT. Specificity for no lesions on colonoscopy was comparable to existing molecular diagnostic tests.

Trial Registration

ClinicalTrials.gov Identifier: NCT04739722.

Low Incidence of Colorectal Advanced Neoplasia During Surveillance in Individuals with a Family History of Colorectal Cancer

BACKGROUND

Family history of colorectal cancer (CRC) is used to stratify individuals into risk categories which determine timing of initial screening and ongoing CRC surveillance. Evidence for long-term CRC risk following a normal index colonoscopy in family history populations is limited.

AIMS

To assess the incidence of advanced neoplasia and associated risk factors in a population undergoing surveillance colonoscopies due to family history of CRC.

METHODS

Surveillance colonoscopy findings were examined in 425 individuals with a family history of CRC, a normal index colonoscopy and a minimum of 10 years of follow-up colonoscopies. Advanced neoplasia risk was determined for three CRC family history categories (near-average, medium and high-risk), accounting for demographics and time after the first colonoscopy.

RESULTS

The median follow-up was 13.5 years (IQR 11.5-16.0), with an incidence of advanced neoplasia of 14.35% (61/425). The number of affected relatives and age of CRC diagnosis in the youngest relative did not predict the risk of advanced neoplasia (p > 0.05), with no significant differences in advanced neoplasia incidence between the family history categories (p = 0.16). Patients ≥ 60 years showed a fourfold (HR 4.14, 95% CI 1.33-12.89) higher advanced neoplasia risk during surveillance than those < 40 years at index colonoscopy. With each subsequent negative colonoscopy, the risk of advanced neoplasia at ongoing surveillance was reduced.

CONCLUSIONS

The incidence of advanced neoplasia was low (14.35%), regardless of the family history risk category, with older age being the main risk for advanced neoplasia. Delaying onset of colonoscopy or lengthening surveillance intervals could be a more efficient use of resources in this population.

Frequency of endoscopic photodocumentation of large colorectal polyps

BACKGROUND AND AIMS

Colonoscopy quality affects colorectal cancer (CRC) incidence and mortality. The U.S. Multi-Society Task Force on Colorectal Cancer strongly recommends photodocumentation (PD) of lesions ≥10 mm in size (ie, large polyps [LPs]) pre-resection and suggests PD postresection to enhance the quality of colonoscopy. No studies have assessed the frequency of LP PD. We evaluated the frequency of and factors associated with PD of LPs.

METHODS

Reports from endoscopists performing ≥50 colonoscopies with LP resection between 2016 and 2021 were reviewed. The frequency of LP PD pre-resection and post-resection and factors associated with PD were collected. A composite score of 2 quality metrics (PD of completeness of examination and bowel preparation quality) was created. Endoscopists were divided into 2 tiers based on the frequency of the score on all included examinations: Tier 1, ≥95% of examinations; and Tier 2, <95% of examinations. Univariate and multivariate analyses were used to assess factors associated with PD.

RESULTS

A total of 1322 colonoscopies, 1693 LPs, and 25 endoscopists were included in this study. PD of LPs occurred in 1392 (82%) pre-resection and in 878 (52%) post-resection. Factors associated with pre-resection PD include endoscopist subspecialty (colorectal surgery vs gastroenterology: odds ratio [OR], .12; 95% confidence interval [CI], .04-.42); >1 LP on examination (2 vs 1 LP: OR, .41 [95% CI, .27-.61]; and ≥3 vs 1 LP: OR, .41 [95% CI, .24-.70]), and longer withdrawal time (OR, 1.02; 95% CI, 1.01-1.04).

CONCLUSIONS

We provide the first data on PD of LP pre-resection and post-resection, which can inform future benchmarking in this area. The implications of PD on metachronous advanced neoplasia need to be studied.

Adoption of colonoscopy surveillance intervals in subjects who received polypectomy in southern China: A cost-effectiveness analysis

BACKGROUND AND AIM

We aimed to evaluate the cost-effectiveness of different colonoscopy intervals among average-risk (5 vs 10 years) and high-risk (1 vs 3 years) southern Chinese populations.

METHODS

We constructed a Markov model with a hypothetical population of 100 000 individuals aged 50-85 years. Average risk was defined as 1-2 non-advanced adenomas (tubular adenoma sized < 10 mm without high-grade dysplasia). High risk was defined as ≥ 3 non-advanced adenomas or any advanced adenoma (adenoma sized ≥ 10 mm, with high-grade dysplasia, or with villous/tubulovillous histology). Three strategies were compared: a 5/1 strategy (average-risk subjects: 5-year interval; high-risk subjects: 1-year interval), a 10/3 strategy, and a control strategy (a 10/10 strategy). Costs (US dollar), quality-adjusted-life-years, incremental cost-effectiveness ratio, and net health benefit were calculated. If the incremental cost-effectiveness ratio of one strategy against another was less than willingness-to-pay ($24 302 US/quality-adjusted-life-years), the strategy was more cost-effective than another.

RESULTS

Compared with the 10/3 strategy, the 5/1 strategy involved more costs and effects (incremental cost-effectiveness ratio = $40 044 US/quality-adjusted life-years). When the 10/10 strategy was regarded as the control, the 5/1 strategy had a higher incremental cost-effectiveness ratio than the 10/3 strategy ($26 056 vs $10 344 US/quality-adjusted life-years). Furthermore, the 10/3 strategy had the highest net health benefit.

CONCLUSIONS

A 10/3 interval was more cost-effective than a 5/1 interval. From an economic perspective, our findings supported a 10-year interval for average-risk individuals and a 3-year interval for high-risk subjects. The findings could help form the optimal colonoscopy interval for average-risk and high-risk patients.

Third Eye? The Assistance of Artificial Intelligence (AI) in the Endoscopy of Gastrointestinal Neoplasms

Gastrointestinal cancers are characterized by high incidence and mortality. However, there are well-established methods of screening. The endoscopy exam provides the macroscopical image and enables harvesting the tissue samples for further histopathological diagnosis. The efficiency of endoscopies relies not only on proper patient preparation, but also on the skills of the personnel conducting the exam. In recent years, a number of reports concerning the application of artificial intelligence (AI) in medicine have arisen. Numerous studies aimed to assess the utility of deep learning/ neural network systems supporting endoscopies. In this review, we summarized the most recent reports and randomized clinical trials regarding the application of AI in screening and surveillance of gastrointestinal cancers among patients suffering from esophageal, gastric, and colorectal cancer, along with the advantages, limitations, and controversies of those novel solutions.

A Multilevel Primary Care Intervention to Improve Follow-Up of Overdue Abnormal Cancer Screening Test Results: A Cluster Randomized Clinical Trial

Importance

Realizing the benefits of cancer screening requires testing of eligible individuals and processes to ensure follow-up of abnormal results.

Objective

To test interventions to improve timely follow-up of overdue abnormal breast, cervical, colorectal, and lung cancer screening results.

Design, Setting, and Participants

Pragmatic, cluster randomized clinical trial conducted at 44 primary care practices within 3 health networks in the US enrolling patients with at least 1 abnormal cancer screening test result not yet followed up between August 24, 2020, and December 13, 2021.

Intervention

Automated algorithms developed using data from electronic health records (EHRs) recommended follow-up actions and times for abnormal screening results. Primary care practices were randomized in a 1:1:1:1 ratio to (1) usual care, (2) EHR reminders, (3) EHR reminders and outreach (a patient letter was sent at week 2 and a phone call at week 4), or (4) EHR reminders, outreach, and navigation (a patient letter was sent at week 2 and a navigator outreach phone call at week 4). Patients, physicians, and practices were unblinded to treatment assignment.

Main Outcomes and Measures

The primary outcome was completion of recommended follow-up within 120 days of study enrollment. The secondary outcomes included completion of recommended follow-up within 240 days of enrollment and completion of recommended follow-up within 120 days and 240 days for specific cancer types and levels of risk.

Results

Among 11 980 patients (median age, 60 years [IQR, 52-69 years]; 64.8% were women; 83.3% were White; and 15.4% were insured through Medicaid) with an abnormal cancer screening test result for colorectal cancer (8245 patients [69%]), cervical cancer (2596 patients [22%]), breast cancer (1005 patients [8%]), or lung cancer (134 patients [1%]) and abnormal test results categorized as low risk (6082 patients [51%]), medium risk (3712 patients [31%]), or high risk (2186 patients [18%]), the adjusted proportion who completed recommended follow-up within 120 days was 31.4% in the EHR reminders, outreach, and navigation group (n = 3455), 31.0% in the EHR reminders and outreach group (n = 2569), 22.7% in the EHR reminders group (n = 3254), and 22.9% in the usual care group (n = 2702) (adjusted absolute difference for comparison of EHR reminders, outreach, and navigation group vs usual care, 8.5% [95% CI, 4.8%-12.0%], P < .001). The secondary outcomes showed similar results for completion of recommended follow-up within 240 days and by subgroups for cancer type and level of risk for the abnormal screening result.

Conclusions and Relevance

A multilevel primary care intervention that included EHR reminders and patient outreach with or without patient navigation improved timely follow-up of overdue abnormal cancer screening test results for breast, cervical, colorectal, and lung cancer.

Trial Registration

ClinicalTrials.gov Identifier: NCT03979495.

What do 'false-positive' stool tests really mean? Data from the New Hampshire colonoscopy registry

We utilized the population-based New Hampshire Colonoscopy Registry to calculate false discovery rates (FDR) and positive predictive values (PPVs) using three 'positive' colonoscopy definitions. Understanding the frequency of meaningful 'true positive' mt-sDNA and Fecal Immunochemical Test (FIT) results can optimize the use of these colorectal cancer (CRC) screening tests. We calculated FDR (positive stool test followed by negative colonoscopy divided by all positive stool tests) and PPV for mt-sDNA and FIT cohorts using the following definitions: 1) DeeP-C Study (CRC, adenomas/serrated polyps ≥ 1 cm, villous/High Grade Dysplasia); 2) < 10 year US Multi-Society Task Force (USMSTF) follow-up: DeeP-C findings & ≥1 sessile serrated polyps (SSPs) < 1 cm (with/without dysplasia) or ≥ 1 tubular adenomas < 1 cm. 3) Clinically Significant: DeeP-C + USMSTF + clinically significant serrated polyps: traditional serrated adenomas, SSPs, hyperplastic polyps (HPs) > 1 cm, and 5-9 mm proximal HPs. The sample included 549 mt-sDNA + and 410 FIT + and patients (mean age 66.4, 43.0% male). Using the most limited definition of positive colonoscopy, DeeP-C, FDR was 71.9% for mt-sDNA + and 81.7% for FIT +. Using the USMSTF definition, FDR decreased substantially: mt-sDNA+:33.2% and FIT+:47.6%. Adding all CSSPs resulted in the lowest FDR: mt-sDNA+:32.2% and FIT+:47.1%. Decreasing FDRs corresponded to increasing PPVs: mt-sDNA+:28.1% and FIT+:18.3% (DeeP-C definition) and mt-sDNA+:67.8% and FIT+:52.9% (DeeP-C + USMSTF + CSSP) (Table 1). FDRs decreased substantially when the definition of positive exams included all significant precancerous findings. These data present a comprehensive understanding of false positive outcomes at colonoscopies following positive stool tests, which to our knowledge is the first such analysis.

Evaluation of Computer-Aided Detection During Colonoscopy in the Community (AI-SEE): A Multicenter Randomized Clinical Trial

INTRODUCTION

There has been increasing interest in artificial intelligence in gastroenterology. To reduce miss rates during colonoscopy, there has been significant exploration in computer-aided detection (CADe) devices. In this study, we evaluate the use of CADe in colonoscopy in community-based, nonacademic practices.

METHODS

Between September 28, 2020, and September 24, 2021, a randomized controlled trial (AI-SEE) was performed evaluating the impact of CADe on polyp detection in 4 community-based endoscopy centers in the United States Patients were block-randomized to undergoing colonoscopy with or without CADe (EndoVigilant). Primary outcomes measured were adenomas per colonoscopy and adenomas per extraction (the percentage of polyps removed that are adenomas). Secondary end points included serrated polyps per colonoscopy; nonadenomatous, nonserrated polyps per colonoscopy; adenoma and serrated polyp detection rates; and procedural time.

RESULTS

A total of 769 patients were enrolled (387 with CADe), with similar patient demographics between the 2 groups. There was no significant difference in adenomas per colonoscopy in the CADe and non-CADe groups (0.73 vs 0.67, P = 0.496). Although the use of CADe did not improve identification of serrated polyps per colonoscopy (0.08 vs 0.08, P = 0.965), the use of CADe increased identification of nonadenomatous, nonserrated polyps per colonoscopy (0.90 vs 0.51, P < 0.0001), resulting in detection of fewer adenomas per extraction in the CADe group. The adenoma detection rate (35.9 vs 37.2%, P = 0.774) and serrated polyp detection rate (6.5 vs 6.3%, P = 1.000) were similar in the CADe and non-CADe groups. Mean withdrawal time was longer in the CADe group compared with the non-CADe group (11.7 vs 10.7 minutes, P = 0.003). However, when no polyps were identified, there was similar mean withdrawal time (9.1 vs 8.8 minutes, P = 0.288). There were no adverse events.

DISCUSSION

The use of CADe did not result in a statistically significant difference in the number of adenomas detected. Additional studies are needed to better understand why some endoscopists derive substantial benefits from CADe and others do not. ClinicalTrials.gov number: NCT04555135.

The carbon footprint of ambulatory gastrointestinal endoscopy

BACKGROUND

Endoscopy is considered the third highest generator of waste within healthcare. This is of public importance as approximately 18 million endoscopy procedures are performed yearly in the USA and 2 million in France. However, a precise measure of the carbon footprint of gastrointestinal endoscopy (GIE) is lacking.

METHODS

This retrospective study for 2021 was conducted in an ambulatory GIE center in France where 8524 procedures were performed on 6070 patients. The annual carbon footprint of GIE was calculated using "Bilan Carbone" of the French Environment and Energy Management Agency. This multi-criteria method accounts for direct and indirect greenhouse gas (GHG) emissions from energy consumption (gas and electricity), medical gases, medical and non-medical equipment, consumables, freight, travel, and waste.

RESULTS

GHG emissions in 2021 were estimated to be 241.4 tonnes CO2 equivalent (CO2e) at the center, giving a carbon footprint for one GIE procedure of 28.4 kg CO2e. The main GHG emission, 45 % of total emissions, was from travel by patients and center staff to and from the center. Other emission sources, in rank order, were medical and non-medical equipment (32 %), energy consumption (12 %), consumables (7 %), waste (3 %), freight (0.4 %), and medical gases (0.005 %).

CONCLUSIONS

This is the first multi-criteria analysis assessing the carbon footprint of GIE. It highlights that travel, medical equipment, and energy are major sources of impact, with waste being a minor contributor. This study provides an opportunity to raise awareness among gastroenterologists of the carbon footprint of GIE procedures.