Colorectal Cancer Surveillance Research Articles

Chinese national clinical practice guidelines on prevention, diagnosis and treatment of early colorectal cancer.

The incidence and mortality of colorectal cancer (CRC) in China are increasing in recent years. The clarified pathogenesis and detectable precancerous lesions of CRC make it possible to prevent, screen, and diagnose CRC at an early stage. With the development of endoscopic and surgical techniques, the choice of treatment for early CRC is also worth further discussion, and accordingly, a standard follow-up program after treatment needs to be established. This clinical practice guideline (CPG) was developed following the recommended process of the World Health Organization, adopting Grading of Recommendations Assessment, Development and Evaluation (GRADE) in assessing evidence quality, and using the Evidence to Decision framework to formulate clinical recommendations, thereby minimizing bias and increasing transparency of the CPG development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guides to ensure the guideline's completeness and transparency. This CPG comprises 46 recommendations concerning prevention, screening, diagnosis, treatment, and surveillance of CRC. In these recommendations, we have indicated protective and risk factors for CRC and made recommendations for chemoprevention. We proposed a suitable screening program for CRC based on the Chinese context. We also provided normative statements for the diagnosis, treatment, and surveillance of CRC based on existing clinical evidence and guidelines. The 46 recommendations in this CPG are formed with consideration for stakeholders' values and preferences, feasibility, and acceptability. Recommendations are generalizable to resource-limited settings with similar CRC epidemiology pattern as China.

Systematic review: risk prediction models for metachronous advanced colorectal neoplasia after polypectomy.

Colorectal cancer (CRC) is the fourth leading cause of cancer death globally. CRC surveillance is a common indication for colonoscopy, representing a considerable burden for endoscopy services. Accurate identification of high-risk patients who would benefit from more intensive surveillance, as well as low-risk patients suitable for less frequent follow-up, could improve the effectiveness of surveillance protocols and resource use. Our aim was to identify and critically appraise published risk models for the occurrence of metachronous advanced colorectal neoplasia (ACN), defined here as CRC or advanced adenomas detected during surveillance colonoscopy. We searched PubMed and EMBASE for primary research studies reporting the development and/or validation of multivariable models that predict metachronous ACN risk. Screening of studies for inclusion, data extraction, and risk of bias assessment were conducted by two researchers independently. We identified nine studies describing nine risk models. Six models were internally validated and two were externally validated. No model underwent both internal and external validation. Good model discrimination (concordance index>0.7) was reported for two models during internal validation and for one model during external validation. Calibration was acceptable when assessed (n=4). Methodological limitations and a high risk of bias were observed for all studies. Several published models predicting metachronous ACN risk showed some promise. However, adherence to methodological standards was limited, and only two models were externally validated. Head-to-head comparisons of existing models using populations independent from model development cohorts should be prioritized to identify models suitable for use in clinical practice.

Colonoscopy and Upper Endoscopy Surveillance in Lynch Syndrome: A Longitudinal Study From a Large Tertiary Healthcare System

Background and AimsLynch syndrome (LS) is caused by pathogenic mutations in mismatch repair (MMR) genes. There is limited data on differences in colorectal cancer (CRC) surveillance by MMR genes, and an international consensus on surveillance based on genes is not established. We aimed to evaluate colonoscopy and EGD surveillance outcomes and compare CRC surveillance findings by the mutated gene. Methods101 patients with LS were included and colonoscopy results were compared by MMR mutation. Primary outcomes included the development and recurrence of adenoma, CRC, high-grade dysplasia (HGD), advanced adenoma (AA), and sessile serrated lesions (SSL). Logistic regressions evaluated the relationship between genes and the development or recurrence of primary outcomes. Survival analysis evaluated primary outcomes in patients with > 2 colonoscopies. EGD results were summarized. Results327 colonoscopies were reviewed. Compared to PMS2, MLH1 was associated with a higher risk of AA/HGD/CRC development (OR 9.85, 95% CI: 1.97-77.24) and MSH2 was associated with a higher risk of adenoma development (OR 4.17, 95% CI: 1.11-17.61). Among those with >2 colonoscopies, MLH1 (HR 18.98, 95% CI: 1.31-274.51) and MSH6 (HR 15.03, 95% CI: 1.16-194.65) had a higher risk of SSL compared to MSH2. Among patients who had adenoma detected once, MLH1 had a higher risk of adenoma recurrence compared to MSH6 (OR 14.59, 95% CI: 1.53-244.30) and PMS2 (OR 47.15, 95% CI: 4.26-984.28). MSH2 had a higher risk of adenoma recurrence compared to PMS2 (OR 11.89, 95% CI: 1.38-164.78). Of 170 EGDs, an actionable finding was identified in 16% of patients during their first three EGDs. ConclusionSurveillance colonoscopy outcomes differed in patients with Lynch Syndrome and suggest the need to guide surveillance based on MMR gene mutation.

Evaluación de la sensibilidad y especificidad de la sigmoidoscopia en comparación con la colonoscopia en la detección de actividad inflamatoria intestinal en el seguimiento de pacientes con colitis ulcerosa

IntroductionUlcerative colitis (UC) is a chronic disease characterized by periods of inflammatory activity and remission, which vary from the rectum to the proximal colon. Currently, mucosal healing is a long-term goal in the management of inflammatory bowel disease, with colonoscopy and sigmoidoscopy being the recommended tools for evaluation. ObjectiveTo assess the effectiveness of both examinations in determining the presence of inflammatory activity in the follow-up of patients with UC. MethodsRetrospective observational study analyzing colonoscopies performed as part of the follow-up of UC patients between January 2021 and July 2023 by gastroenterologists from the Inflammatory Bowel Disease Program at the Clínica Universidad de los Andes. The study compared endoscopic and histological activity observed in the rectosigmoid region with that found in the rest of the colon. Sensitivity and specificity were determined using concordance and correlations tests. ResultsA very good concordance and correlation were observed regarding endoscopic findings, with a Kappa index of 0.97 and a Spearman coefficient of 0.97. The Positive Predictive Value (PPV) of sigmoidoscopy for endoscopic activity was 1, and the Negative Predictive Value (NPV) was 0.96. In relation to histological activity, the concordance had a Kappa index of 0.93 and a Spearman coefficient of 0.93, with a PPV of sigmoidoscopy for histological activity being 1 and an NPV of 0.91. ConclusionThis cohort suggests that sigmoidoscopy is a cost-effective option for evaluating mucosal healing in UC patients in symptomatic and biomarker remission. However, complete colonoscopy should be considered in cases of discrepancies with the clinical picture or in colorectal cancer surveillance.

Extent of investigation and management of cases of ‘unexplained’ mismatch repair deficiency (u-dMMR): a UK Cancer Genetics Group consensus

BackgroundMismatch repair deficiency (dMMR) is a characteristic feature of cancers linked to Lynch syndrome. However, in most cases, it results from sporadic somatic events rather than hereditary factors. The term...

Effect of alverine citrate plus simethicone in colonoscopy: a randomized controlled trial.

Colonoscopy is the standard procedure for screening, and surveillance of colorectal cancer, including the treatment for colonic lesions. Colonic spasm is an important problem from colonoscopy that affects both surgeons and patients. The spasm also might be the cause of longer cecal intubation time, difficulty of the procedure, and increased pain. Previous reports indicated that antispasmodic agents can decrease such symptoms. Therefore, we conducted this study to investigate the cecal intubation time of antispasmodic agents. A single blinded randomized controlled trial was conducted from 01/11/2020 to 31/08/2021. One hundred four patients were allocated to antispasmodic agent group and control group, in 1:1 ratio. The efficacy of median (range) cecal intubation time showed similar results of 5 (2, 14) and 5 (2, 15) minutes with no statistically significant difference. The mean scores of all domains i.e., pain, spasm, cleanliness, and difficulty were better in the antispasmodic agent group about 2.6 (1.4), 1.8 (0.8), 2.4 (0.9), and 2.0 (0.9), respectively, than control group but there were spasm and cleanliness showed statistically significant difference. Moreover, the satisfaction scores showed better efficacy in decreased spasm, decreased difficulty, and increased cleanliness than control group. Prescribing of antispasmodic drugs before colonoscopy might be the choice of treatment for the patients. The antispasmodic drugs will be beneficial to both of the patient and the doctor.

ChatGPT4 Outperforms Endoscopists for Determination of Postcolonoscopy Rescreening and Surveillance Recommendations

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. 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. 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). 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.

Surveillance colonoscopy findings in asymptomatic participants over 75 years of age.

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. 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. 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). 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.

Artificial intelligence for dysplasia detection during surveillance colonoscopy in patients with ulcerative colitis: A cross-sectional, non-inferiority, diagnostic test comparison study

Background and study aimHigh-definition virtual chromoendoscopy, along with targeted biopsies, is recommended for dysplasia surveillance in ulcerative colitis patients at risk for colorectal cancer. Computer-aided detection (CADe) systems aim to improve colonic adenoma detection, however their efficacy in detecting polyps and adenomas in this context remains unclear. This study evaluates the CADe Discovery™ system's effectiveness in detecting colonic dysplasia in ulcerative colitis patients at risk for colorectal cancer. Patients and methodsA prospective cross-sectional, non-inferiority, diagnostic test comparison study was conducted on ulcerative colitis patients undergoing colorectal cancer surveillance colonoscopy between January 2021 and April 2021. Patients underwent virtual chromoendoscopy (VCE) with iSCAN 1 and 3 with optical enhancement. One endoscopist, blinded to CADe Discovery™ system results, examined colon sections, while a second endoscopist concurrently reviewed CADe images. Suspicious areas detected by both techniques underwent resection. Proportions of dysplastic lesions and patients with dysplasia detected by VCE or CADe were calculated. ResultsFifty-two patients were included, and 48 lesions analyzed. VCE and CADe each detected 9 cases of dysplasia (21.4% and 20.0%, respectively; p=0.629) in 8 patients and 7 patients (15.4% vs. 13.5%, respectively; p=0.713). Sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy for dysplasia detection using VCE or CADe were 90% and 90%, 13% and 5%, 21% and 2%, 83% and 67%, and 29.2% and 22.9%, respectively. ConclusionsThe CADe Discovery™ system shows similar diagnostic performance to VCE with iSCAN in detecting colonic dysplasia in ulcerative colitis patients at risk for colorectal cancer.

NFKB2 mediates colorectal cancer cell immune escape and metastasis in a STAT2/PD‐L1‐dependent manner

This study systematically analyzed the molecular mechanism and function of nuclear factor kappa B subunit 2 (NFKB2) in colorectal cancer (CRC) to investigate the potential of NFKB2 as a therapeutic target for CRC. Various experimental techniques, including RNA sequencing, proteome chip assays, and small molecule analysis, were used to obtain a deeper understanding of the regulation of NFKB2 in CRC. The results revealed that NFKB2 was upregulated in a significant proportion of patients with advanced hepatic metastasis of CRC. NFKB2 played an important role in promoting tumor growth through CD8+ T-cell exhaustion. Moreover, NFKB2 directly interacted with signal transducer and activator of transcription 2 (STAT2), leading to increased phosphorylation of STAT2 and the upregulation of programmed death ligand 1 (PD-L1). Applying a small molecule inhibitor of NFKB2 (Rg5) led to a reduction in PD-L1 expression and improved response to programmed death-1 blockade-based immunotherapy. In conclusion, the facilitated NFKB2-STAT2/PD-L1 axis may suppress immune surveillance in CRC and targeting NFKB2 may enhance the efficacy of immunotherapeutic strategies. Our results provide novel insights into the molecular mechanisms underlying the contribution of NFKB2 in CRC immune escape.

Synchronous early rectal adenocarcinoma and neuroendocrine tumour: A treatment strategy

IntroductionSynchronous colorectal adenocarcinoma with neuroendocrine tumour (NET) are a unique combination of tumours. These may be incidental lesions, usually a histopathological diagnosis rather than a clinical diagnosis from symptoms, examination or even gross appearances.AimThis paper aims to highlight our management strategy on manging a middle-aged woman with synchronous rectal adenocarcinoma and NET.Case studyA 53-year-old woman presented with lower gastrointestinal bleeding with constitutional symptoms. Clinical examination and colonoscopy revealed a classical rectal adenocarcinoma, confirmed via biopsy. However, the final histopathology reports of the resected tumour revealed an early rectal adenocarcinoma with synchronous NET.Results and discussionWe review the relevant literature and a discussion regarding guidelines available for diagnosis, follow-up and surveillance of this rare case.ConclusionsThere are no current guidelines for surveillance colonoscopy after detecting gastrointestinal NET, particularly synchronous tumours. NET may be another colorectal cancer risk factor with similar mutations and common genetic markers. Clinicians should consider doing a colonoscopy when or if their patients are diagnosed with any gastrointestinal NET. Detection of any NET warrants a thorough evaluation of the whole colon for colorectal cancer and close surveillance so that timely management can be achieved.

Abstract 2180: Modulation of immune infiltration patterns in inflammation-associated colorectal cancer through rice bran-based dietary strategies

Abstract The correlation between gut microbiota dysbiosis and inflammation-associated colorectal cancer (CRC) has generated considerable interest in dietary interventions targeting immune modulation. Our prior study demonstrated the colon cancer protective effects of rice bran (RB) and ex vivo Bifidobacterium longum fermented rice bran (FRB) diet intervention against azoxymethane/dextran sodium sulfate (AOM/DSS)-induced CRC in gut microbiota-intact specific pathogen-free mice (SPF). RB showed higher levels of protection compared to FRB against CRC, as evidenced by diminished neoplastic lesion size and restored colonic epithelial integrity. The major objective of the present study was to leverage cutting-edge multispectral imaging technique for simultaneous detection of multiple immune cells markers and for a comprehensive analysis of distinct immune landscapes. We also performed spatial correlations within the tumor microenvironment of AOM/DSS-SPF mice undergoing RB and FRB dietary interventions. The primary focus was on T cell subtypes including cytotoxic T cells, helper T cells, regulatory T (Treg) cells, natural killer (NK) cells, NKT cells, B cells and macrophages (MΦ) subtypes (M1 MΦ, and M2 MΦ) to uncover the intricacies of the immune landscape and the interplay for CRC prevention through dietary intervention. The results indicated that RB intervention for 15 weeks led to reductions in overall T cell subtypes in the colonic tissue, particularly Treg cells, which are associated with protecting tumors against immune surveillance in CRC. On the other hand, FRB intervention also resulted in reductions in overall T cell subtypes but exhibited higher infiltration of NK cells and proinflammatory M1 macrophages in the colonic tissue after 15 weeks. While an increased presence of NK cells might be beneficial in countering CRC, the infiltration of M1 macrophages could potentially lessen the impact of FRB compared to RB intervention in CRC protection. The outcomes suggest that the better protective efficacy of non-fermented RB diets is linked to the modulation of Treg cell infiltration, whereas the efficacy of the FRB diet is to some extent limited by the presence of M1 macrophages. Overall, this study provides valuable insights into the complex immune landscape influenced by RB and FRB interventions in a murine model of inflammation-induced CRC, and a novel mechanism for the immunomodulatory effects of dietary RB interactions with gut microbiota. In the future, observing immune modulation throughout diet intervention would enhance our understanding of the role played by these immune cells. Citation Format: Robin Kumar, Lakshmi Sai Pratyusha Bugata, Md. Imtiazul Kabir, Rajesh Agarwal, Elizabeth P. Ryan, Komal Raina. Modulation of immune infiltration patterns in inflammation-associated colorectal cancer through rice bran-based dietary strategies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2180.

Exogenous Insulin Therapy Is Associated with the Risk of Advanced Colorectal Adenoma in Patients with Diabetes Mellitus.

Exogenous insulin therapy increases systemic exposure to insulin which may promote the development of colorectal neoplasia. We sought to evaluate the association between exogenous insulin therapy and the incidence of advanced adenoma in type 2 diabetes mellitus. A retrospective cohort study was conducted from January 1, 2007, to January 1, 2018, in a regional health system serving the United States Philadelphia metropolitan area, Central New Jersey, and South Central Pennsylvania. Study patients consisted of a random sample of patients with type 2 diabetes mellitus aged 40-80years who had undergone two rounds of colonoscopy examinations. The exposure was cumulative duration of insulin therapy (i.e., no use, 1-365days and > 365days). The outcome was time to incident advanced adenoma. Of the 975 eligible patients, 184 patients accumulated > 365days of insulin therapy before the follow-up colonoscopy. The mean (standard deviation) duration between the two rounds of colonoscopy examination was 5.1 (2.9) years among the insulin users and 5.3 (3.9) years among non-users. Compared to no insulin exposure, receiving > 365days of insulin therapy was associated with an increased incidence of advanced adenoma (adjusted hazard ratio [aHR] 4.84, 95% confidence interval [CI] 2.82-8.30), right-sided advanced adenoma (aHR 5.48, 95% CI 2.90-10.35), and 3 or more adenomas (aHR 2.61, 95% CI 1.46-4.69) at the follow-up colonoscopy examination. Insulin therapy is associated with an increased risk of advanced adenoma and may serve as a novel risk-stratification factor to enhance the efficiency of existing colorectal cancer screening and surveillance programs.

Abstract 2313 Use of Big Data to Assess Disparities in Adherence to Colorectal Cancer Surveillance: a Biological, Environmental, and Social Determinants of Health Integrated Approach

Abstract 2313 Use of Big Data to Assess Disparities in Adherence to Colorectal Cancer Surveillance: a Biological, Environmental, and Social Determinants of Health Integrated Approach

Dynamic Prediction of Advanced Colorectal Neoplasia in Inflammatory Bowel Disease

Colonoscopic surveillance is recommended in patients with colonic inflammatory bowel disease (IBD) given their increased risk of colorectal cancer (CRC). We aimed to develop and validate a dynamic prediction model for the occurrence of advanced colorectal neoplasia (aCRN, including high-grade dysplasia and CRC) in IBD. We pooled data from six existing cohort studies from Canada, the Netherlands, the UK, and the USA. Patients with IBD and an indication for CRC surveillance were included if they underwent at least one follow-up procedure. Exclusion criteria included prior aCRN, prior colectomy, or an unclear indication for surveillance. Predictor variables were selected based on literature. A dynamic prediction model was developed using a landmarking approach based on Cox proportional hazard modelling. Model performance was assessed with Harrell's concordance-statistic (discrimination) and by calibration curves. Generalizability across surveillance cohorts was evaluated by internal-external cross-validation. The surveillance cohorts comprised 3,731 patients, enrolled and followed-up in the time period 1973-2021, with a median follow-up of 5.7 years (26,336 patient-years of follow-up); 146 individuals were diagnosed with aCRN. The model contained eight predictors, with a cross-validation median c-statistic of 0.74 and 0.75 for a 5- and 10-year prediction window, respectively. Calibration plots showed good calibration. Internal-external cross-validation results showed medium discrimination and reasonable to good calibration. The new prediction model showed good discrimination and calibration, however, generalizability results varied. Future research should focus on formal external validation and relate predicted aCRN risks to surveillance intervals prior to clinical application.

Improving Concordance Between Clinicians With Australian Guidelines for Bowel Cancer Prevention Using a Digital Application: Randomized Controlled Crossover Study.

Australia's bowel cancer prevention guidelines, following a recent revision, are among the most complex in the world. Detailed decision tables outline screening or surveillance recommendations for 230 case scenarios alongside cessation recommendations for older patients. While these guidelines can help better allocate limited colonoscopy resources, their increasing complexity may limit their adoption and potential benefits. Therefore, tools to support clinicians in navigating these guidelines could be essential for national bowel cancer prevention efforts. Digital applications (DAs) represent a potentially inexpensive and scalable solution but are yet to be tested for this purpose. This study aims to assess whether a DA could increase clinician adherence to Australia's new colorectal cancer screening and surveillance guidelines and determine whether improved usability correlates with greater conformance to guidelines. As part of a randomized controlled crossover study, we created a clinical vignette quiz to evaluate the efficacy of a DA in comparison with the standard resource (SR) for making screening and surveillance decisions. Briefings were provided to study participants, which were tailored to their level of familiarity with the guidelines. We measured the adherence of clinicians according to their number of guideline-concordant responses to the scenarios in the quiz using either the DA or the SR. The maximum score was 18, with higher scores indicating improved adherence. We also tested the DA's usability using the System Usability Scale. Of 117 participants, 80 were included in the final analysis. Using the SR, the adherence of participants was rated a median (IQR) score of 10 (7.75-13) out of 18. The participants' adherence improved by 40% (relative risk 1.4, P<.001) when using the DA, reaching a median (IQR) score of 14 (12-17) out of 18. The DA was rated highly for usability with a median (IQR) score of 90 (72.5-95) and ranked in the 96th percentile of systems. There was a moderate correlation between the usability of the DA and better adherence (rs=0.4; P<.001). No differences between the adherence of specialists and nonspecialists were found, either with the SR (10 vs 9; P=.47) or with the DA (13 vs 15; P=.24). There was no significant association between participants who were less adherent with the DA (n=17) and their age (P=.06), experience with decision support tools (P=.51), or academic involvement with a university (P=.39). DAs can significantly improve the adoption of complex Australian bowel cancer prevention guidelines. As screening and surveillance guidelines become increasingly complex and personalized, these tools will be crucial to help clinicians accurately determine the most appropriate recommendations for their patients. Additional research to understand why some practitioners perform worse with DAs is required. Further improvements in application usability may optimize guideline concordance further.

A123 THE EFFECTS OF INFLAMMATORY BOWEL DISEASE ON THE MANAGEMENT AND OUTCOMES OF COMPLEX POLYPS IN PATIENTS UNDERGOING SURVEILLANCE COLONOSCOPY: A RETROSPECTIVE COHORT STUDY

Abstract Background The influence of inflammatory bowel disease (IBD) on the outcomes of complex polyps remains an area of uncertainty. Aims To investigate the impact of IBD on the management and outcomes of complex polyps during surveillance colonoscopy. Methods This retrospective cohort study utilized a prospectively collected database, involving patients who underwent surveillance colonoscopy for colorectal cancer or IBD surveillance who were identified to have complex polyps between February 2019 and December 2020 in Southwestern Ontario. Patient demographics, disease characteristics, medication history, polyp description and management were analyzed. The data were summarized in median and interquartile range for continuous variable and frequency and percentage for categorical variables. Characteristics between IBD and non-IBD were compared using the Wilcoxon rank sum test and Fisher’s exact test, as appropriate. Results 383 patients were included in the study, of which 27 individuals had IBD (5 Crohn's disease, 13 ulcerative colitis, and 9 indeterminate colitis). Patients with IBD were generally younger than their non-IBD counterparts (median age 61 vs 67 respectively). No significant differences were identified in terms of rates of complete polyp removal (17.70 % vs 22.22 %, pampersand:003C0.602), residual polyps after resection (76.97% vs 70.37%, pampersand:003C0.476), repeat removal attempts (84.27% vs 74.07%, pampersand:003C0.179), or surgical intervention (88.76% vs 88.89%, pampersand:003C0.99). A higher proportion of IBD patients were managed by gastroenterologists vs other endoscopists (81.48% vs. 40.17%, p ampersand:003C 0.001). No significant differences in complex polyp characteristics were observed, except in difficult locations of complex polyps were more common in the non-IBD cohort (55.34% vs 25.93%, pampersand:003C0.004). Conclusions In this retrospective cohort study, IBD does not appear to influence the management or outcome of complex polyps. Larger studies are required given the small IBD cohort size in this study. Funding Agencies None

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. MethodsThis 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. ResultsOf 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. ConclusionsThis 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.

Current Approaches for Monitoring of Patients with Inflammatory Bowel Diseases: A Narrative Review.

Patients with inflammatory bowel diseases (IBD) require proactive monitoring both during the active phase to evaluate therapeutic response and during the remission phase to evaluate relapse or colorectal cancer surveillance. However, monitoring may vary between patients with ulcerative colitis (UC) and Crohn's disease (CD), with distinct tools and intervals. This narrative review aims to focus on modern approaches to IBD monitoring, considering international guidelines and expert consensus. The most recent European diagnostic guidelines advocate a combination of clinical, laboratory, endoscopic, and radiological parameters to evaluate the disease course of patients with IBD. Unfortunately, the conventional symptom-based therapeutic approach does not improve long-term outcomes and there is no single ideal biomarker available. Endoscopy plays a key role in evaluating response to therapy as well as monitoring disease activity. Recently, bedside intestinal ultrasound (IUS) has gained increasing interest and diffusion as it appears to offer several advantages including the monitoring of therapeutic response. In light of growing clinical advances, we present a schematic evidence-based monitoring algorithm that can be easily applied in clinical practice which combines all major monitoring modalities, including noninvasive tools such as IUS and video-capsule endoscopy.

Colorectal Cancer Prevention: Is Chat Generative Pretrained Transformer (Chat GPT) ready to Assist Physicians in Determining Appropriate Screening and Surveillance Recommendations?

To determine whether a publicly available advanced language model could help determine appropriate colorectal cancer (CRC) screening and surveillance recommendations. Poor physician knowledge or inability to accurately recall recommendations might affect adherence to CRC screening guidelines. Adoption of newer technologies can help improve the delivery of such preventive care services. An assessment with 10 multiple choice questions, including 5 CRC screening and 5 CRC surveillance clinical vignettes, was inputted into chat generative pretrained transformer (ChatGPT) 3.5 in 4 separate sessions. Responses were recorded and screened for accuracy to determine the reliability of this tool. The mean number of correct answers was then compared against a control group of gastroenterologists and colorectal surgeons answering the same questions with and without the help of a previously validated CRC screening mobile app. The average overall performance of ChatGPT was 45%. The mean number of correct answers was 2.75 (95% CI: 2.26-3.24), 1.75 (95% CI: 1.26-2.24), and 4.5 (95% CI: 3.93-5.07) for screening, surveillance, and total questions, respectively. ChatGPT showed inconsistency and gave a different answer in 4 questions among the different sessions. A total of 238 physicians also responded to the assessment; 123 (51.7%) without and 115 (48.3%) with the mobile app. The mean number of total correct answers of ChatGPT was significantly lower than those of physicians without [5.62 (95% CI: 5.32-5.92)] and with the mobile app [7.71 (95% CI: 7.39-8.03); P < 0.001]. Large language models developed with artificial intelligence require further refinements to serve as reliable assistants in clinical practice.