Colorectal Cancer Surveillance Research Articles

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.

Screening and surveillance for hereditary colorectal cancer.

Hereditary colorectal cancer is a type of cancer that is caused by a genetic mutation. Individuals with a family history of colorectal cancer, or who have a known hereditary syndrome, are at an increased risk of developing the disease. Screening and surveillance are important tools for managing the risk of hereditary colorectal cancer. Screening involves a combination of tests that can detect precancerous or cancerous changes in the colon and rectum. Surveillance involves regular follow-up examinations to monitor disease progression and to identify new developments. The frequency and type of screening and surveillance tests may vary depending on an individual's risk factors, genetic profile, and medical history. However, early detection and treatment of hereditary colorectal cancer can significantly improve patient outcomes and reduce mortality rates. By implementing comprehensive screening and surveillance strategies, healthcare providers can help individuals at risk of hereditary colorectal cancer to receive timely interventions and make informed decisions about their health. Specific examples of screening and surveillance tests for hereditary colorectal cancer include colonoscopy, genetic testing, and imaging tests. In this review article, we will discuss detailed screening and surveillance of hereditary colorectal cancer.

Management of colorectal cancer screening backlog due to the COVID-19 pandemic: A retrospective analysis of the use of a colorectal cancer screening clinical-decision support tool in Argentina

BackgroundThe COVID-19 pandemic created a backlog in colorectal cancer (CRC) screening and surveillance colonoscopies. The real impact in Argentina is not fully known. GoalTo estimate the impact of the COVID-19 pandemic on CRC prevention by comparing the number of CRC screening and surveillance consults in a clinical decision support-tool used in Argentina before, during and after pandemic lockdown. MethodsWe analyzed data from May 2019 to December 2021 from CaPtyVa, a clinical decision support tool for CRC screening and surveillance. Queries were divided in pre-pandemic (May 2019 to March 2020), lockdown (April 2020 to December 2020), and post-lockdown (January 2021 to December 2021). The number of CRC monthly screening and surveillance visits were compared among the three periods and stratified according to CRC risk. ResultsOverall, 27,563 consults were analyzed of which 9035 were screening and 18,528 were surveillance. Pre-pandemic, the median number of screening consults was 346 per month (IQR25–75 280–410). There was a decrease to 156 (80–210)/month (p<0.005) during lockdown that partially recovered during post-lockdown to 230 (170–290)/month (p=0.05). Pre-pandemic, the median number of surveillance consults was 716 (560–880)/month. They decreased to 354 (190–470)/month during lockdown (p<.05) and unlike screening, completely recovered during post-lockdown to 581 (450–790)/month. ConclusionsThere was a >50% decrease in the number of CRC screening and surveillance consults registered in CaPtyVa during lockdown in Argentina. Post-lockdown, surveillance consults recovered to pre-pandemic levels, but screening consults remained at 66% of pre-pandemic levels. This has implications for delays in CRC diagnoses and patient outcomes.

P536 Outcome of colorectal cancer surveillance in paediatric inflammatory bowel disease: Time for new guidelines?

Abstract Background Paediatric inflammatory bowel disease (IBD) patients have an increased risk of colorectal cancer (CRC). Current guidelines advise to conduct CRC surveillance colonoscopy eight years following IBD diagnosis, or more often in case other risk factors for CRC are present, such as previous findings of colorectal dysplasia, or a concomitant primary sclerosing cholangitis (PSC) diagnosis. However, these guidelines are based on adult data and with no regard to the patient’s age, while frequent endoscopies impose a significant burden on children. In this study, we aimed to estimate the risk of dysplasia and CRC in paediatric IBD patients before the ages of 18 and 27 years. Methods Using the Dutch Nationwide Pathology Databank (PALGA), we examined the incidence and prevalence of dysplasia and CRC in patients up to 27 years in all Dutch paediatric IBD patients diagnosed between 1991 and 2023. Additionally, we assessed the influence of PSC diagnosis on CRC risk. Results Out of the 7,873 patients with biopsy-proven paediatric IBD, 24 developed dysplasia (0.34%) and two (0.025%) developed CRC before the age of 18 years. Out of the 3,425 patients from this cohort currently aged over 26 years, eleven (0.3%) developed CRC between 17 and 27 years. Overall, 120 patients (1.5%) were diagnosed with concomitant PSC, seven (5.8%) of which developed dysplasia and two (1.6%) of which developed CRC before the age of 27 years. The median time between IBD diagnosis and CRC diagnosis was 9.5 years in this cohort. Overall, CRC incidence before the age of 27 years decreased between 1991 and 2023. Additional clinical data on IBD localisation, severity of the disease, and concomitant diagnoses could not reliably be obtained from this database. Conclusion In this retrospective study, we found low prevalence of dysplasia and CRC in paediatric IBD patients, both before the age of 18 years and before the age of 27 years. PSC prevalence was low in this cohort, since only biopsy-proven PSC was included. However, we showed that PSC significantly increased the risk of CRC in paediatric IBD patients. Based on our findings it could be proposed to initiate CRC surveillance beyond the age of 18 years by experienced adult gastroenterologists, except in case of a concomitant PSC diagnosis.

P464 Could Chat Generative Pre-Trained Transformer (ChatGPT) be an AI-provided friend of the patients for frequently asked questions concerning their IBD management? An evidence- and guidelines-controlled textual analysis of AI-provided outputs

Abstract Background Artificial intelligence (AI) is gradually and potentially entering the everyday lives of patients with Inflammatory Bowel Disease (IBD). Systems such as Chat Generative Pre-Trained Transformer (ChatGPT), based on large language models (LLM), are now within reach. It is necessary to weigh whether these LLM systems can be real generators of medical information and whether the latter is generated based on credible databases and evidence. This study evaluated and analysed whether the outputs of ChatGPT to common questions from IBD patients can provide credible and scientifically reliable outputs. Methods IBD-expert physicians retrieved a list of ten IBD frequently asked questions in their clinical practice. The ten with the highest frequency (Q1-10) were collected from the total number of questions and then input on ChatGPT (see Table) on three different days (18th, 19th, and 20th August 2023), and each output generated by the chatbot was categorised as O1, O2, and O3. The same research team evaluated the AI-generated responses by ChatGPT for each question by objectively comparing them with the available evidence (provided by meta-analyses, systematic reviews and ECCO guidelines). Results Q1 O1-3 were reliable, with a correct definition of the absence of definitive therapy for IBD. In Q2 O1-3, ChatGPT failed to clarify the lack of solid evidence for nutritional therapy in IBD. Q3 O1-3 provided corrected guidance on repeat endoscopic examinations for IBD. Q4 O1-3 did not provide reliable answers on removing topical therapy in ulcerative colitis. In Q5 O1-3 good advice was given to the IBD patient on how to plan a pregnancy. Q6 O1-3 brought out the lack of ChatGPT update (stopped in September 2021), limiting the range of new oral small molecule therapies available for the IBD patient. In Q7 O1-3 ChatGPT correctly outlined the need for individual risk stratification for endoscopic surveillance of colorectal cancer. In Q8 and Q9 O1-3 ChatGPT correctly weighed the risk of infection/cancer during biologic therapy and how heritability is only one piece of the pathogenetic puzzle of IBD. Finally, in Q10 he correctly elucidated the possibility of biological therapy preventing post-operative recurrence of Crohn's disease. Conclusion ChatGPT is a potentially useful complementary tool for communicating with IBD patients. It is necessary to improve the degree to which it is updated and sources on appropriate databases (e.g., Scopus, Web of Science, and MEDLINE). Ultimately, there are still significant limitations. Much of the latest findings, in fact, are excluded from ChatGPT evaluation. A portion of the outputs provided are partially incorrect or not fully detailed and not yet ready to be released to the patient without a physician filter.

Surveillance of resected metastatic colorectal cancer utilizing circulating DNA.

214 Background: There is limited data to guide surveillance in patients with metastatic colorectal cancer (CRC) who have had curative resection using circulating tumor DNA (ctDNA) in addition to labs and imaging studies. Minimal residual disease (MRD) assays utilize circulating tumor DNA (ctDNA) for the purposes of monitoring for early recurrence and predicting therapeutic response. In this study, we aim to investigate the utility of ctDNA monitoring in the setting of resected metastatic CRC. Methods: Patients were identified through retrospective search at a tertiary care and several satellite settings to identify patients with metastatic CRC who had undergone curative resection and later had ctDNA monitoring (using Signatera assay). IRB approval was obtained for the study. We recorded demographic information (sex, race, age at diagnosis), disease characteristics (stage at diagnosis, site of primary cancer, site of metastasis), treatment regimens, clinical outcomes (recurrence, survival) and follow-up data. Our primary outcome was to evaluate the rate of recurrence in patients with metastatic CRC who had curative resection in two different population, ctDNA positive or ctDNA negative, post-surgery. Results: We identified 35 patients with a median age of 55 years (range 31 – 82) at the time of metastatic diagnosis. In this study cohort, 20 (57%) were female; 23 (66%) were white, and 10 (29%) were African American. 22 (63%) patients had left-sided primary tumors and the remaining (47%) had right-sided primary tumors. At the time of presentation, 23 (66%) patients had synchronous metastases and 12 (34%) developed metachronous metastases. ctDNA positivity was reported in 21 (60%) pts post-curative therapy. Median time from curative therapy to ctDNA positivity was 62 days. 22 (63%) pts experienced recurrence of disease post-curative resection. Median time to recurrence after ctDNA test was first positive was 6.6 months. Among 21 patients in ctDNA positive group, 19 (86%) developed recurrences and among 14 ctDNA negative patients, only 3 (21%) developed recurrences (p-value &lt;0.01). Recurrence free survival was significantly shorter in patients who were ctDNA positive post surgery (Median RFS: 7.17 months, 95% CI: 4.4-18.0 months) compared to those who were ctDNA negative (Median RFS: 30.8 months; 95% CI: 12.6-NR) (p-value=0.005). Conclusions: In patients with metastatic CRC who underwent curative resection ctDNA may have utility in predicting disease recurrence at both academic and community sites. Larger studies are needed for validation of ctDNA as an adjunct test for surveillance in broader population.

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.

Characteristics, clinical outcomes, and prognostic factors of colorectal cancer in patients with Crohn's disease: American versus Korean tertiary referral center perspectives.

Crohn's disease (CD) exhibits variability in colorectal cancer (CRC) incidence and prognostic factors due to diverse clinical and behavioral characteristics, presenting inconsistencies between Western and Eastern patients. This study compared clinical characteristics between CD patients with CRC from the US and Korean tertiary referral centers and defined the prognostic factors related to mortality. Retrospective study. We reviewed the electronic medical records of 236 adult CD patients with colorectal adenocarcinoma evaluated at Mayo Clinic Rochester, Florida, or Arizona (N = 200) and Asan Medical Center in Korea (N = 36) between January 1989 and August 2022. Asan patients had a younger age, shorter CD duration, more colonic involvement (L2 plus L3), penetrating behavior, perianal fistula, and shorter biological treatment duration before CRC diagnosis than Mayo patients. Furthermore, despite significant differences in body mass index, smoking status, primary sclerosing cholangitis, immunomodulators, CRC diagnosis period, clinical presentation, CRC location, surgery, and some histopathological details between the two groups, overall survival was not statistically different (p value, 0.29, log-rank test). Advanced age (adjusted hazard ratio (aHR), 1.03 per year; 95% confidence interval (CI), 1.01-1.04; p value, <0.01), unresectable CRC (aHR, 5.02; 95% CI, 2.49-10.12; p value, <0.01), and advanced CRC stage (aHR, 1.45 per stage; 95% CI, 1.07-1.97; p value, 0.02) were significantly associated with increased risk of death. CD remission at CRC diagnosis (aHR, 0.26; 95% CI, 0.08-0.91; p value, 0.04), CRC diagnosis period of 2011-2022 (aHR relative to 1989-2000, 0.46; 95% CI, 0.25-0.87; p value, 0.02), and CRC diagnosis by surveillance (aHR, 0.56; 95% CI, 0.32-0.98; p value, 0.04) were significantly associated with decreased risk of death. Notably, some clinical features of CD with CRC differed between Asan and Mayo patients; however, overall survival was not different. CD remission, CRC surveillance, and more recent diagnosis of CRC were associated with a reduced risk of death.

Explorative cost-effectiveness analysis of colorectal cancer recurrence detection with next-generation sequencing liquid biopsy in Spain, France, and Germany.

Next-generation sequencing liquid biopsy (NGS-LB) for colorectal cancer (CRC) detection and surveillance remains an expensive technology as economies of scale have not yet been realized. Nevertheless, the cost of sequencing has decreased while sensitivity has increased, raising the question of whether cost-effectiveness (CE) has already been achieved from the perspective of European healthcare systems. This health economic (HE) modeling study explores the CE of NGS-LB for CRC based on direct treatment costs compared to standard care without liquid biopsy in Spain, France, and Germany. A structured literature search was used to collect evidence from 2009 to 2020 on the stage-dependent quality of life (quality-adjusted life-years, QALY), efficacy, and total direct treatment costs (TDC) of NGS-LB. A decision-analytic Markov model was developed. Over the remaining lifetime, cumulative life expectancy (LE), TDC, and QALYs were calculated for 60-year-old men and women in CRC stage III with different assumed effects of NGS-LB of 1% or 3% on improved survival and reduced stage progression, respectively. The use of NGS-LB increases LE by 0.19 years in Spanish men (France: 0.19 years, Germany: 0.13 years) and by 0.21 years in Spanish women (France: 0.21 years, Germany: 0.14 years), respectively. The 3% discounted cost per QALY gained was 35,571.95 € for Spanish men (France: 31,705.15 €, Germany: 37,537.68 €) and 35,435.71 € for Spanish women (France: 31,295.57 €, Germany: 38,137.08 €) in the scenario with 3% improved survival and reduced disease progression. Compared to the other two countries, Germany has by far the highest TDC, which can amount to >80k euros in the last treatment year. In this explorative HE modeling study, NGS-LB achieves generally accepted CE levels in CRC treatment from the health system perspective in three major European economies under assumptions of small improvements in cancer recurrence and survival. Confirmation of these findings through clinical trials is encouraged.

Occurrence of Colorectal Cancer After a Negative Colonoscopy in Patients With Inflammatory Bowel Disease: A Systematic Review and Meta-analysis.

Despite the application of colorectal cancer (CRC) surveillance guidelines, the detection of early neoplastic lesions might be difficult in patients with inflammatory bowel disease (IBD). To explore the risk of post-colonoscopy CRC (PCCRC) in patients with IBD we performed a systematic review and meta-analysis. A systematic literature search was performed (PROSPERO; no. CRD42023453049). We included studies reporting the 3-year PCCRC (PCCRC-3y) prevalence, according to World Endoscopy Organization (WEO)-endorsed definition, in IBD and non-IBD patients. As primary outcome we evaluated the PCCRC-3y prevalence, according to WEO definitions, in IBD- and non-IBD patients and calculated the odds ratio (OR). The secondary outcome was to assess risk factors for PCCRC development in IBD patients. Three retrospective observational cohort studies were included. The pooled PCCRC-3y rate in patients with IBD was 30.8% [95% confidence interval (CI)=24.4-37.5%] and in non-IBD patients was 6.8% (95%CI=6.2-7.4%). The PCCRC-3y occurrence in IBD patients was significantly higher than that in non-IBD patients (OR=6.04; 95%CI=4.04-9.4; I2=95%), but a high heterogeneity among studies was noted. Furthermore, patients with ulcerative colitis (UC) had a significantly higher prevalence of PCCRC than patients with Crohn's Disease (CD): 30.9% (95%CI=27.8-34.2%) vs. 22.3% (95%CI=18-27%), respectively (OR=1.6, 95%CI=1.2-2.2; I2=0%). One-third of CRC in IBD patients were PCCRC, and these numbers were significantly higher when compared with those in non-IBD patients. Furthermore, the prevalence of PCCRC in patients with UC was higher compared to those with CD. However, prospective studies are required to better characterize risk factors for PCCRC development in patients with IBD.

A case of exuberant endoscopic presentation of asymptomatic eosinophilic colitis.

Eosinophilic colitis is a rare entity characterized by a broad range of gastrointestinal symptoms and idiopathic infiltration of eosinophils in the colon. This condition is most likely underreported due to the absence of standardized diagnostic criteria. We present the case of a 72-year-old man who underwent an outpatient colorectal cancer surveillance colonoscopy without gastrointestinal complaints. Colonoscopy revealed a diffuse micronodular pattern of the colonic mucosa, with histopathological analysis showing a polymorphic infiltrate rich in eosinophils in the lamina propria. The patient was kept under surveillance, with a repeat colonoscopy showing persistent endoscopic and histological findings consistent with eosinophilic colitis. The patient remains asymptomatic. This case is unique from both clinical and endoscopic perspectives due to the asymptomatic course of this rare condition and the illustrative iconography.

Plasma Assay of Cell-Free Methylated DNA Markers of Colorectal Cancer: A Tumor-Agnostic Approach to Monitor Recurrence and Response to Anticancer Therapies.

Radiographic surveillance of colorectal cancer (CRC) after curative-intent therapy is costly and unreliable. Methylated DNA markers (MDMs) detected primary CRC and metastatic recurrence with high sensitivity and specificity in cross-sectional studies. This study evaluated using serial MDMs to detect recurrence and monitor the treatment response to anti-cancer therapies. A nested case-control study was drawn from a prospective cohort of patients with CRC who completed curative-intent therapy for CRC of all stages. Plasma MDMs were assayed vis target enrichment long-probe quantitative-amplified signal assays, normalized to B3GALT6, and analyzed in combination with serum carcinoembryonic antigen to yield an MDM score. Clinical information, including treatment and radiographic measurements of the tumor burden, were longitudinally collected. Of the 35 patients, 18 had recurrence and 17 had no evidence of disease during the study period. The MDM score was positive in 16 out of 18 patients who recurred and only 2 of the 17 patients without recurrence. The MDM score detected recurrence in 12 patients preceding clinical or radiographic detection of recurrent CRC by a median of 106 days (range 90-232 days). Plasma MDMs can detect recurrent CRC prior to radiographic detection; this tumor-agnostic liquid biopsy approach may assist cancer surveillance and monitoring.

The Possible Preventative Role of Lactate- and Butyrate-Producing Bacteria in Colorectal Carcinogenesis.

: The gut microbiome has emerged as a key player that mechanistically links various risk factors to colorectal cancer (CRC) etiology. However, the role of the gut microbiome in CRC pathogenesis remains unclear. This study aimed to characterize the gut microbiota in healthy controls (HCs) and patients with colorectal adenoma (AD) and CRC in subgroups based on sex and age. : Study participants who visited the hospital for surveillance of CRC or gastrointestinal symptoms were prospectively enrolled, and the gut microbiome was analyzed based on fecal samples. : In terms of HC-AD-CRC sequence, commensal bacteria, including lactate-producing (Streptococcus salivarius) and butyrate-producing (Faecalibacterium prausnitzii, Anaerostipes hadrus, and Eubacterium hallii) bacteria, were more abundant in the HC group than in the AD and CRC groups. In the sex comparison, the female HC group had more lactate-producing bacteria (Bifidobacterium adolescentis, Bifidobacterium catenulatum, and Lactobacillus ruminis) than the male HC group. In age comparison, younger subjects had more butyrate-producing bacteria (Agathobaculum butyriciproducens and Blautia faecis) than the older subjects in the HC group. Interestingly, lactate-producing bacteria (B. catenulatum) were more abundant in females than males among younger HC group subjects. However, these sex- and age-dependent differences were not observed in the AD and CRC groups. : The gut microbiome, specifically lactate- and butyrate-producing bacteria, which were found to be abundant in the HC group, may play a role in preventing the progression of CRC. In particular, lactate-producing bacteria, which were found to be less abundant in healthy male controls may contribute to the higher incidence of CRC in males.

Associations between patient factors and successful colon capsule endoscopy - A prospective cohort study.

To establish patient factors associated with a successful colon capsule endoscopy (CCE) test. This prospective cohort study used data collected from patients who underwent CCE as part of the ScotCap evaluation prior to April 2020. A CCE was defined as successful if the capsule visualized the whole colon and rectum (complete test) with sufficient bowel cleansing to permit assessment of the colonic mucosa (adequate bowel preparation). Factors from patients in symptomatic and surveillance groups were analysed for associations with a successful test, complete test, adequate bowel preparation and requirement for further procedure using univariate, multivariate logistic, least absolute shrinkage and selection operator regression. Data from 263 symptomatic and 137 surveillance patients were analysed. There was an association between a symptomatic patient's age and a successful test (OR = 0.97, 95% CI: 0.95-0.99), adequate bowel preparation (OR = 0.97, 95% CI: 0.94-1.00) and further procedure requirement (OR = 1.04, 95% CI: 1.02-1.06). An association was found, for symptomatic patients, between a faecal immunochemical test result in the range 10-399 μg/g and a further procedure (OR = 2.32, 95% CI: 1.23-4.48). In patients undergoing surveillance for previous colorectal cancer (OR = 0.42, 95% CI: 0.18-0.97), had previous bowel resection surgery (OR = 0.43, 95% CI: 0.19-0.98) or took a beta blocker medication (OR = 0.32, 95% CI: 0.11-0.88), an association was found with further procedure requirement. Among symptomatic patients, younger age was associated with obtaining a successful CCE test. Clinicians could consider patient selection based on these results to improve the rate of successful testing in clinical practice.