Ulrik Deding

Background/Objectives: Colonoscopy is the standard examination for many symptomatic patients referred for lower-gastrointestinal investigation, but it is resource-intensive and may be a burdensome experience. Colon capsule endoscopy (CCE) offers a minimally invasive, sedation-free first-line examination, although clinically important findings, inadequate cleansing or incomplete transit can generate downstream colonoscopy. DanCap aims to compare the costs and clinical consequences of a CCE-first pathway with routine conventional colonoscopy (CC). Methods: DanCap is a single-centre, cluster-allocated crossover trial at Odense University Hospital, Denmark. General practice clinics follow CCE or CC according to the parity of their pre-existing provider number, with pathways crossing after 200 consecutive CCE participants; no trial-generated random allocation sequence is used. Eight hundred symptomatic adults aged >18 years referred for expedited lower-gastrointestinal investigation are planned. CCE participants with suspected cancer, any polyp ≥6 mm, inadequate cleansing or an incomplete examination are referred for colonoscopy. The primary outcome is pathway cost. Registered secondary outcomes and prespecified process measures include polyp and colorectalcancer detection, examination quality, reinvestigation and patient-reported consequences. FIT and microbiome are registered secondary outcomes; participation in the substudy is optional and the analyses are exploratory within the CCEpathway. Primary analyses will follow the assigned pathway and account for GP clinic clustering, period and allocation sequence. Expected Results: The trial will quantify the resource use and clinical consequences of implementing CCE in routine symptomatic practice. Conclusions: DanCap is intended to inform decisions about CCE pathway implementation rather than to establish unbiased whole-cohort test sensitivity or specificity. Trial registration: ClinicalTrials.gov NCT06475560; first submitted 20 June 2024 and first posted 26 June 2024. Recruitment began on 27 November 2024; the registry listed the study as recruiting when last updated on 19 March 2026.

Background: Colon capsule endoscopy (CCE) has been proposed as a non-invasive alternative to colonoscopy for colorectal cancer (CRC) screening, offering greater patient comfort and potentially reducing healthcare burden. However, its cost-effectiveness in population-based screening remains uncertain. Methods: This study used a state-transition (Markov) model to simulate lifetime outcomes of CRC screening in Denmark, Scotland, and Spain, comparing the standard pathway based on fecal immunochemical testing (FIT) followed by colonoscopy with an alternative pathway replacing colonoscopy with CCE after a positive FIT result. The model incorporated costs (2024 euros), quality-adjusted life-years (QALYs), and CRC cases avoided, applying a yearly discount rate of 3%. Deterministic sensitivity analyses explored uncertainty in capsule cost, adherence, and reinvestigation rates for non-advanced polyps. Results: Across all settings, CCE resulted in higher costs but slightly increased effectiveness and utility (mean QALYs 28.7 vs. 28.8; CRC detected 0.032–0.034 vs. 0.035–0.037 per person). Incremental cost-effectiveness ratios (ICER) ranged from €43,538 in Spain to €136,930 in Denmark per additional CRC detected. Capsule cost was the main driver of ICER variation, whereas adherence rates had minimal effect on cost-effectiveness. Changes in the prevalence of non-advanced polyps had a modest impact, except when capsule prices were high. Conclusions: Overall, replacing colonoscopy with CCE slightly increases detection and health gains at the expense of higher costs. Cost-effectiveness largely depends on capsule price and adherence. Artificial intelligence-assisted CCE interpretation may further improve diagnostic and economic performance, potentially supporting adoption in large-scale CRC screening programs.

Background: Endoscopy units throughout the world have seen a substantial increase in colonoscopy activity. One way to keep patient waiting time acceptable could be to introduce alternative diagnostic modalities. Colon capsule endoscopy has been proven to have a high diagnostic accuracy, yet the re-investigation rates reported are too high. Faecal haemoglobin concentration may offer a valid measure for triaging patients between diagnostic modalities, due to its association with colonic pathology. Objective: To investigate the re-investigation rate and risk classification in complete colon capsule endoscopies in a screening population stratified by faecal haemoglobin concentration. Design: Cross-sectional analyses of a data set derived from the intervention arm of a large randomised controlled trial, CareForColon2015, conducted in the Region of Southern Denmark between August 2020 and December 2022. Methods: Complete colon capsule endoscopy investigations were identified, and the proportions of investigations leading to re-investigation by colonoscopy were calculated, stratified by faecal haemoglobin concentration. Further, the odds of re-investigation were estimated by logistic regression models and the odds of increased risk classification by ordinal regression models. Results: The re-investigation rate was 58.6% in 1413 complete colon capsule endoscopies out of 2030 procedures. There were no significant differences ( p = 0.312) in re-investigation rates between faecal haemoglobin concentration subgroups with 58.2%, 61.1% and 62.7% in the groups of 100–249, 250–499 and >499 ng hb/mL buffer, respectively. The odds of referral for re-investigation did not differ significantly either. The odds of increased risk classification (i.e. higher than level one) was 1.17 (CI 95% 0.92; 1.49, p = 0.211) for concentrations between 250 and 499 ng hb/mL buffer, and 1.40 (CI 95% 1.12; 1.77, p = 0.003) for concentrations above 499 ng hb/mL buffer, compared to 100–249 ng hb/mL buffer. Conclusion: Faecal haemoglobin concentration did not prove to be a stand-alone selection parameter for diagnostic modality in a faecal immunochemical test-positive colorectal cancer screening population, although it was significantly associated with an increased risk classification.

Objective: Incomplete investigations challenge the clinical use of colon capsule endoscopy (CCE). This results in added cost to healthcare systems and added discomfort to patients. In order to potentially lower the re-investigation rate, we aimed to investigate the association between multiple patient characteristics and complete CCE. Methods: In 2020, the CareForColon2015 (CFC2015) Trial was initiated in the Region of Southern Denmark, investigating the performance of CCE in colorectal cancer screening. Data from the CFC2015 Trial were combined with data from multiple national registers. Completion rates were calculated and their relation to the different patient characteristics was analysed in univariate and multivariate logistic regression models. Results: We analysed 1472 participants, of whom 1016 (69.1%) had complete investigations. We investigated the associations between 17 patient characteristics and complete CCE investigation. The multivariate analysis showed that smokers and heavy drinkers had a higher probability of a complete investigation, with ORs of 1.69 (95% CI 1.12 to 2.55) and 2.72 (95% CI 1.52 to 4.87), respectively, compared with non-consumers. We also found that increasing income was associated with increased odds of CCE completion (OR 1.78, 95% CI 1.30 to 2.43, for the highest quartile). High body mass index (>40) and self-reported constipation or laxative use were significantly associated with incomplete CCE, with ORs of 0.40 (95% CI 0.17 to 0.97) and 0.65 (95% CI 0.47 to 0.90), respectively. Conclusion: This study tested multiple factors for association with CCE completion. The results indicate that some factors are associated with higher odds of completion, while others are associated with lower odds of completion. These results confirm that specific patient characteristics correlate with the odds of complete investigation. This can, in turn, be used to determine the individual diagnostic pathway. Additional studies are needed for less frequently reported characteristics and to further support these findings.

Identifying unique polyps in colon capsule endoscopy (CCE) images is a critical yet challenging task for medical personnel due to the large volume of images, the cognitive load it creates for clinicians, and the ambiguity in labeling specific frames. This paper formulates this problem as a multi-instance learning (MIL) task, where a query polyp image is compared with a target bag of images to determine uniqueness. We employ a multi-instance verification (MIV) framework that incorporates attention mechanisms, such as variance-excited multi-head attention (VEMA) and distance-based attention (DBA), to enhance the model's ability to extract meaningful representations. Additionally, we investigate the impact of self-supervised learning using SimCLR to generate robust embeddings. Experimental results on a dataset of 1912 polyps from 754 patients demonstrate that attention mechanisms significantly improve performance, with DBA L1 achieving the highest test accuracy of 86.26\% and a test AUC of 0.928 using a ConvNeXt backbone with SimCLR pretraining. This study underscores the potential of MIL and self-supervised learning in advancing automated analysis of Colon Capsule Endoscopy images, with implications for broader medical imaging applications.

Introduction: A large bowel cancer chemoprevention potential has been demonstrated by the consumption of carrots, which represent the major dietary source of polyacetylenes. Their interaction with cancer cells and enzyme systems of animals and humans has been systematically investigated over the last 15 years and has now been characterised as anti-inflammatory compounds with antineoplastic effect. Our objective is to investigate whether selected carrot species with a high content of the polyacetylenes falcarinol (FaOH) and falcarindiol (FaDOH) prevent neoplastic transformation and growth in humans, without side effects. Methods and analysis: We will conduct a multicentre prospective binational (Denmark and Sweden) randomised controlled trial, with the aim to test the clinical effects of adjuvant treatment with carrot juice in patients who had an excision of high-risk colon adenomas. Patients from six centres will be randomised to receive either anti-inflammatory juice made of carrots high in FaOH and FaDOH or placebo. We will compare the proportion of participants with recurrent adenoma and mean size of them, found in the 1-year follow-up colonoscopy between the two randomised groups. Ethics and dissemination: Informed written consent will be obtained from all participants before randomisation. The study was approved by the regional ethics committee in Denmark (ref. S-20230072) and Sweden (ref. 2024-04732-01 ). After completion of the trial, we plan to publish two articles in high-impact journals: one article on primary and secondary outcomes, respectively. Trial registration number: NCT06335420 .

In the Danish health care system, follow-up colonoscopy is standard after a colonic diverticulitis episode in order to exclude malignancy. Colon capsule endoscopy (CCE) is a diagnostic alternative to colonoscopy. This study compared patient-reported outcomes of CCE versus colonoscopy after diverticulitis episodes. A randomized controlled trial was conducted in patients with computed tomography-verified diverticulitis from Odense University Hospital. Patients were randomized to either CCE or colonoscopy 4–6 weeks after discharge. The primary outcome was patient-reported experienced physical and mental discomfort related to the procedures. Secondary outcomes were expected physical and mental discomfort, examination preference, proportion of complete examinations, and frequency of polyps and colorectal cancer. 159 patients were randomized, with 148 receiving their allocated intervention and 83 completing the questionnaires. Demographic data were comparable between the two groups. No adverse events were observed. Patients expected greater physical and mental discomfort with colonoscopy than with CCE. However, no significant difference was found in experienced physical and mental discomfort between CCE and colonoscopy. For hypothetical future events, 49% of patients would prefer CCE, 13% would prefer colonoscopy, and 38% did not know. Complete examinations were reported for 84% of CCEs and 92% of colonoscopies. No malignant lesions were found. CCE was a safe follow-up procedure after a diverticulitis episode. CCE was preferred to colonoscopy by most patients who reported their experience. No difference was observed regarding experienced physical and mental discomfort between the groups completing the questionnaires.

Objective Colon capsule endoscopy (CCE) has emerged as a promising alternative for investigating lower gastrointestinal symptoms. However, its adoption has been limited due to concerns about cost-effectiveness, significantly influenced by follow-up endoscopy rates (FERs). Understanding CCE’s FERs is crucial for its integration into routine clinical practice. We synthesised the evidence to evaluate the overall rate of further investigation in CCE. Design A systematic review and meta-analysis were conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data sources Medline, Embase, and PubMed were searched through 15 August 2024. Eligibility criteria Studies included reporting FERs after CCE, including subsequent endoscopic procedures and radiological imaging. There were no language restrictions or limitations in CCE referral indications, patient recruitment criteria, or pathologies investigated. Data extraction and synthesis All studies were independently screened and extracted two times by four reviewers. A random-effects model was used for meta-analysis and meta-regression to identify key contributing factors. Results 2850 participants from 19 studies were included in the analysis. Compared with the key performance indicators for FERs in colonoscopy (0.10–0.15) and CT colonography (0.25), the pooled FER for CCE was found to be 0.42 (95% CI 0.34 to 0.50). The meta-regression analysis identified complete transit rates and adequate bowel cleansing quality as factors inversely associated with FERs. Furthermore, the CCE2 capsule demonstrated a higher reinvestigation risk than CCE1, likely due to its improved diagnostic accuracy. Although CCE indications were associated with lower FERs, subgroup analysis did not reach statistical significance with high heterogeneity. Conclusion This study highlights significant FERs for CCE and identifies key contributing factors, emphasising the importance of appropriate patient selection to reduce reinvestigation needs. Future research should focus on improving completion rates, bowel preparation protocols, and refining CCE indications. This will minimise environmental impact and enhance cost-effectiveness and patient satisfaction. PROSPERO registration number CRD42024567959.

Background Colonoscopy is among the standard tests for colorectal cancer (CRC) screening. However, uptake varies, and alternatives such as colon capsule endoscopy (CCE) are available. The uptake and detection rate of clinically significant neoplasia with CCE, compared with colonoscopy, remain unclear in this setting. Objective The primary objective of this study was to compare the detection rates of advanced neoplasia between CCE and colonoscopy, using a pathway in which the study group could choose between the two procedures, while the control group was offered only colonoscopy. Design A randomised, intention-to-treat trial was conducted among Danish CRC screening participants who tested positive with a faecal immunochemical test (FIT). The trial compared the detection rate of advanced neoplasia (primary outcome) and the uptake rate of both approaches between the two arms. Results A total of 473 684 invitations were sent to 396 676 individuals, with 62.6% returning the test. Among them, 11 075 tests were positive (4.5%), with no significant differences between the two study groups. Among FIT-positive cases, the uptake for colonoscopy was 91.1% in the control arm and 91.7% in the study arm, where participants had a choice of methods. In the study arm, 45.8% preferred CCE, 11.4% preferred colonoscopy and 42.8% had no preference and underwent colonoscopy. Ultimately, 69.9% of patients who initially opted for CCE were later referred for colonoscopy. The rate of advanced neoplasia detection was similar between the groups: 0.67% in the study arm versus 0.64% in the control arm. Conclusion Offering CCE as an alternative to colonoscopy did not significantly alter the detection rate of advanced neoplasia, nor did it increase uptake in a screening programme with high adherence to colonoscopy following a positive FIT test. Instead, it led to a very high rate of secondary colonoscopies. Therefore, CCE cannot be recommended in this setting. Trial registration number NCT04049357 (ClinicalTrials.gov)