Post-colonoscopy Colorectal Cancer Research Articles

Comparing Right-sided Colon Adenoma and Serrated Polyp Miss Rates with Water Exchange and CO2 Insufflation: A Randomized Controlled Trial

INTRODUCTION: Postcolonoscopy colorectal cancers primarily occur in the right-sided colon because of missed adenomas and serrated polyps (SPs). Water exchange (WE) improves cleanliness and visibility of the right-sided colon. We hypothesized that WE could reduce the right-sided colon adenoma (rAMR) and SP miss rate (rSPMR) compared to standard colonoscopy. METHODS: We randomly assigned 386 colonoscopy patients to insertion with either WE or CO2 insufflation. During the first withdrawal, polypectomies were performed up to the hepatic flexure. A second endoscopist, blinded to the insertion technique, reexamined the right-sided colon. The miss rate was determined by dividing the number of additional adenomas or SPs by the total number detected in both examinations. The primary outcome was the combined rAMR and rSPMR. RESULTS: WE significantly decreased the combined rAMR and rSPMR (22.2% vs 32.2%, P < 0.001) and rSPMR alone (22.5% vs 37.1%, P = 0.002) compared to CO2 insufflation, but not rAMR (21.8% vs 29.8%, P = 0.079). Additionally, WE significantly increased the detection of SP per colonoscopy (SPPC) in the right-sided colon (0.95 ± 1.56 vs 0.50 ± 0.79, P < 0.001). Multivariate logistic regression analysis showed that ≥2 SPs in the right-sided colon was an independent predictor of rSPMR (odds ratio [OR], 3.47; 95% confidence interval [CI], 1.89─6.38), along with a higher right-sided colon Boston Bowel Preparation Scale score (OR, 0.55; 95% CI, 0.32─0.94). CONCLUSIONS: The significant reduction in rSPMR and increase in right-sided colon SPPC suggest that colonoscopy insertion using WE is a valid alternative to CO2 insufflation (Clinical trial registration number: NCT04124393).

Screening Colonoscopy to Reduce the Incidence and Mortality of Colorectal Cancer.

Colorectal cancer (CRC) is a major concern because of its increasing incidence and mortality worldwide. Therefore, effective screening strategies are necessary to reduce its incidence. In addition to fecal immunochemical tests and computed tomography colonography, screening colonoscopy is expected to significantly contribute to the reduction of CRC. However, the timing of colonoscopy for CRC screening is not well-defined because of the lack of sufficient data. Additionally, the effectiveness of colonoscopy is affected by various factors known as quality indicators (QIs), such as the performance of the endoscopist; therefore, there are concerns regarding quality assurance. The adenoma detection rate (ADR) is a well-known QI of colonoscopy. Substantial evidence has suggested that improving the ADR could reduce the incidence and mortality of postcolonoscopy CRC. Recent technological advancements have led to the development of image-enhanced endoscopy and the incorporation of artificial intelligence, and their ability to improve the ADR has been assessed. This review focused on screening colonoscopies and QIs and their ability to improve the ADR and incidence and mortality of CRC.

Faecal Volatile Organic Compounds to Detect Colorectal Neoplasia in Lynch Syndrome-A Prospective Longitudinal Multicentre Study.

Non-invasive biomarkers may reduce post-colonoscopy colorectal cancer (CRC) rates and colonoscopy overuse in Lynch syndrome. Unlike faecal immunochemical test (FIT), faecal volatile organic compounds (VOCs) may accurately detect both advanced and non-advanced colorectal neoplasia. The aim of this study was to evaluate the potential of faecal VOCs-separately and with FIT-to guide optimal colonoscopy intervals in Lynch syndrome. Prospective longitudinal multicentre study in which individuals with Lynch syndrome collected faeces before and after high-quality surveillance colonoscopy. VOC-patterns were analysed using field asymmetric ion mobility spectrometry (FAIMS) and gas chromatography-ion mobility spectrometry (GC-IMS) followed by machine learning pipelines, and combined with FIT at 2.55 μg Hb/g faeces. Gas chromatography time-of-flight mass spectrometry analysed individual VOC abundance. Among 200 included individuals (57% female, median 51 years), 62 had relevant neoplasia at colonoscopy: 3 CRC, 6 advanced adenoma (AA), 3 advanced serrated lesion (ASL), and 50 non-advanced adenoma (NAA). Respective sensitivity and negative predictive value for CRC and AA (and also ASL in case of FAIMS) were 100% and 100% using FAIMS (54% specificity), and 89% and 99% using GC-IMS (58% specificity). Respective sensitivity and specificity for any relevant neoplasia were 88% and 44% (FAIMS) and 84% and 28% (GC-IMS); accuracy did not significantly improve upon VOC-FIT. VOC-patterns differed before and after polypectomy (AUC 0.70). NAA showed decreased faecal abundance of butanal, 2-oxohexane, dimethyldisulphide and dimethyltrisulphide. In Lynch syndrome, faecal VOCs may be a promising strategy for postponing colonoscopy and for follow-up after polypectomy. Our results serve as a stepping stone for large validation studies. NL8749.

Application of Duty of Candour legislation in post-colonoscopy colorectal cancer: a prospective cohort study.

Background & Study Aims The study investigates the application of Duty of Candour (DoC) legislation in the context of post-colonoscopy colorectal cancers (PCCRCs). DoC mandates transparent disclosure of notifiable safety incidents to patients in the English National Health Service, including those leading to severe or moderate harm. This study aims to analyse the application of DoC in PCCRCs, improve understanding of the legislation and identify challenges in its implementation. Patients & Methods A national audit of PCCRCs was conducted between September 2021 to May 2022. PCCRCs were identified using linked administrative datasets and root-cause analyses were performed using a structured template. 1,724 PCCRCs were included. 'Avoidability' and harm categorised into specific levels, with guidance provided to improve consistency in judgments. Results 16% of PCCRCs resulted in major harm or death, of which 27%(75) were at least probably avoidable. Hospitals deemed DoC discharge necessary in only 53% of these cases. When including moderate harm, 11% of all PCCRCs would trigger DoC discharge, yet this was deemed necessary in only 41% of these cases. Conclusions There is inconsistent application of DoC in PCCRC cases. Challenges include determining 'avoidability' and harm, particularly when there is a delay in diagnosis. Clearer guidance and definitions of harm are needed to improve adherence to regulations.

Impact of linked color imaging on the proximal adenoma miss rate: a multicenter tandem randomized controlled trial (the COCORICO trial).

Missed lesions are common during standard colonoscopy and are correlated with post-colonoscopy colorectal cancer. Contrast-enhanced technologies have recently been developed to improve polyp detection. We aimed to evaluate the impact of linked color imaging (LCI) on the proximal adenoma miss rate in routine colonoscopy. This national, multicenter, tandem, randomized trial compared the outcomes of colonoscopy with white-light imaging (WLI) versus LCI for polyp detection in the right colon. Two consecutive examinations of the right colon (upstream of the hepatic flexure) were made with WLI and LCI by the same operator. First-pass examination by WLI or LCI was randomized 1:1 after cecal intubation. According to statistical calculations, 10 endoscopy units had to include approximately 700 patients. The primary outcome was proximal adenoma miss rate. Secondary outcomes were the proximal miss rates for sessile serrated lesions (SSL), advanced adenomas, and polyps. 764 patients were included from 1 January 2020 to 22 December 2022, and 686 patients were randomized (345 WLI first vs. 341 LCI first). Both groups were comparable in terms of demographics and indications. The proximal adenoma miss rate was not significantly higher in the WLI-first group (36.7%) vs. the LCI-first group (31.8%) (estimated mean absolute difference: 4.9% [95%CI -5.2% to 15.0%], P = 0.34). There was also no significant difference in miss rates for SSLs, advanced adenomas, and polyps in the proximal colon. In contrast to previous data, this study does not support the benefit of LCI to the proximal adenoma miss rate in routine colonoscopy.

S496 Root Cause Analysis of Post-Colonoscopy Colorectal Cancer in FIT-Positive Individuals: Results From A Nationwide Database

S496 Root Cause Analysis of Post-Colonoscopy Colorectal Cancer in FIT-Positive Individuals: Results From A Nationwide Database

S451 Very Low Rate of Post-Colonoscopy Colorectal Cancer in Individuals at Average-Risk for Colorectal Cancer

S451 Very Low Rate of Post-Colonoscopy Colorectal Cancer in Individuals at Average-Risk for Colorectal Cancer

S435 Characteristics and Most Plausible Explanation for Post-Colonoscopy Colorectal Cancer Cases in a Community-Based Practice

S435 Characteristics and Most Plausible Explanation for Post-Colonoscopy Colorectal Cancer Cases in a Community-Based Practice

Preventing Post-Colonoscopy Colorectal Cancer in Inflammatory Bowel Disease—“The Big Five”

Preventing Post-Colonoscopy Colorectal Cancer in Inflammatory Bowel Disease—“The Big Five”

FP1.11 - An audit of post colonoscopy Colorectal cancers within a Northern Ireland Health and Social Care Trust

Abstract Background Post colonoscopy colorectal cancer (PCCRC) is defined as colorectal cancer found within 48 months of a colonoscopy in which no cancer was found. The British Society of Gastroenterology (BSG) proposes PCCRC rates as a key quality indicator of colonoscopy. Rates documented vary between 2-8%, with higher rates shown in Inflammatory Bowel disease (IBD). The English National Post Colonoscopy Colorectal Audit was established after recommendations from the World Endoscopy Organisation (WEO). We aim to establish the rates of PCCRC within this Health and Social Care Trust (HSCT). Method All CRCs diagnosed in our HSCT between January 2021 to December 2022 were retrospectively reviewed. Our definition for a PCCRC was one diagnosed between 0-48months after a colonoscopy. Information included whether the colonoscopy was complete, quality of bowel preparation, lesions detected, if resection of lesion was complete and if IBD was present. Results In this timeframe 524 CRCs were diagnosed in this HSCT, with 33(6.3%) having had a colonoscopy within the previous 48 months. Of the 33 PCCRCs, 21(63.6%) had a complete colonoscopy, 22(66.6%) had at least fair/satisfactory bowel preparation, 24(72.7%) had a lesion detected and 3(9%) had a prior diagnosis of IBD. Of those who had a lesion detected (n=24), 13(54%) had a complete resection and 10(41.6%) had a biopsy only or incomplete resection. Conclusions Our PCCRC detection rate is in keeping with previous published literature. Further analysis of the 33 cases should provide information on how we can reduce future PCCRCs.

Optimal bowel preparation for colonoscopy.

There is robust evidence to indicate a strong correlation between the bowel preparation status and adenoma detection rate (ADR), which directly impacts the incidence and mortality rate of postcolonoscopy colorectal cancer. Therefore, improving bowel preparation has been of increasing interest. In Japan, commercially available bowel preparation agents include polyethylene glycol, oral sodium sulfate, sodium picosulfate-magnesium citrate, magnesium citrate, and oral sodium phosphate; each has its own strengths and limitations. The timing of administration can also influence the efficacy of bowel preparation and patient tolerability. Furthermore, meta-analyses have suggested predictive factors for inadequate bowel preparation. A detailed understanding of these factors could contribute to reducing the need for repeat colonoscopy within 1 year, as recommended for patients with inadequate bowel preparation. Recent advancements, such as oral sulfate tablets, present promising alternatives with higher patient satisfaction and ADRs than traditional methods. Achieving optimal bowel preparation requires enhanced instructions, individualized regimens, and a comprehensive understanding of patient backgrounds and the characteristics of various bowel preparation agents. This article provides a concise overview of the current status and advancements in bowel preparation for enhancing the quality and safety of colonoscopy.

Fecal Immunochemical Test to Detect Colorectal Neoplasia in Lynch Syndrome: A Prospective Multicenter Study.

Colonoscopy surveillance for Lynch syndrome is burdensome and postcolonoscopy colorectal cancers (CRCs) still occur. The noninvasive fecal immunochemical test (FIT) might guide optimal colonoscopy intervals. Prospective, multicenter observational study in which individuals with Lynch syndrome performed a quantitative FIT before high-quality surveillance colonoscopy. Diagnostic performance of FIT at various thresholds ≤20 μg Hb/g feces was assessed for relevant neoplasia, including advanced neoplasia (CRC, advanced adenomas [AAs] and advanced serrated lesions [ASLs]) and non-advanced adenomas (NAAs). Of the 217 included individuals (59% female, median age 51 years), 4 had CRC, 5 AA, 4 ASL, and 57 NAA as most relevant neoplasia. The lowest FIT positivity threshold (2.5 μg Hb/g feces, 14% positivity rate) maximized detection: 4/4 CRCs, 4/5 AA, 1/4 ASL, and 9/57 NAA were detected, resulting in a sensitivity and negative predictive value of, respectively, 89% and 99% for CRC plus AA, 69% and 97% for advanced neoplasia, and 26% and 72% for all relevant neoplasia (91% specificity for all groups). At equal sensitivity and negative predictive value, specificity for advanced neoplasia optimized to 94% at threshold 4.1 μg/g. Per 100 FITs at threshold 4.1 μg/g, 11 individuals would test positive and thus proceed to colonoscopy, 2 individuals with advanced neoplasia would be missed and 3 individuals would need colonoscopy to detect 1 advanced neoplasia. FIT at thresholds ≤4.1 μg Hb/g feces may be a promising strategy to postpone colonoscopy in approximately 9 of 10 individuals with Lynch syndrome. Large validation studies that also provide gene variant-specific outcomes should be prioritized.

Polyp detection with colonoscopy assisted by the GI Genius artificial intelligence endoscopy module compared with standard colonoscopy in routine colonoscopy practice (COLO-DETECT): a multicentre, open-label, parallel-arm, pragmatic randomised controlled trial

Increased polyp detection during colonoscopy is associated with decreased post-colonoscopy colorectal cancer incidence and mortality. The COLO-DETECT trial aimed to assess the clinical effectiveness of the GI Genius intelligent endoscopy module for polyp detection, comparing colonoscopy assisted by GI Genius (computer-aided detection [CADe]-assisted colonoscopy) with standard colonoscopy in routine practice. We did a multicentre, open-label, parallel-arm, pragmatic randomised controlled trial in 12 National Health Service (NHS) hospitals (ten NHS Trusts) in England, among adults (aged ≥18 years) undergoing planned colonoscopy for gastrointestinal symptoms or for surveillance due to personal or family history (ie, symptomatic indications), or colorectal cancer screening. Randomisation (1:1) to CADe-assisted colonoscopy or standard colonoscopy was done with a web-based dynamic adaptive algorithm, immediately before colonoscopy, with stratification by age group, sex, colonoscopy indication (screening or symptomatic), and NHS Trust. Recruiting staff, participants, and colonoscopists were unmasked to trial allocation; histopathologists, co-chief investigators, and trial statisticians were masked. CADe-assisted colonoscopy consisted of standard colonoscopy plus the GI Genius module active for at least the entire inspection phase of colonoscope withdrawal. The primary outcome was mean adenomas per procedure (total number of adenomas detected divided by total number of procedures); the key secondary outcome was adenoma detection rate (proportion of colonoscopies with at least one adenoma). Analysis was by intention to treat (ITT), with outcomes compared between groups by mixed-effects regression modelling, in which effect estimates were adjusted for randomisation stratification variables. Data were imputed for outcome measures with more than 5% missing values. All participants who underwent colonoscopy were assessed for safety. The trial is registered on ISRCTN (ISRCTN10451355) and ClinicalTrials.gov (NCT04723758), and is complete. Between March 29, 2021, and April 6, 2023, 2032 participants (1132 [55·7%] male, 900 [44·3%] female; mean age 62·4 years [SD 10·8]) were recruited and randomly assigned: 1015 to CADe-assisted colonoscopy and 1017 to standard colonoscopy. 1231 (60·6%) participants were undergoing screening and 801 (39·4%) had symptomatic indications. Mean adenomas per procedure was 1·56 (SD 2·82; n=1001 participants with available data) in the CADe-assisted colonoscopy group versus 1·21 (1·91; n=1009) in the standard colonoscopy group, representing an adjusted mean difference of 0·36 (95% CI 0·14-0·57; adjusted incidence rate ratio 1·30 [95% CI 1·15-1·47], p<0·0001). Adenomas were detected in 555 (56·6%) of 980 participants in the CADe-assisted colonoscopy group versus 477 (48·4%) of 986 in the standard colonoscopy group, representing a proportion difference of 8·3% (95% CI 3·9-12·7; adjusted odds ratio 1·47 [95% CI 1·21-1·78], p<0·0001). Numbers of adverse events were similar between the CADe-assisted colonoscopy and standard colonoscopy groups (adverse events: 25 vs 19; serious adverse events: four vs six), and no adverse events in the CADe-assisted colonoscopy group were deemed to be related to GI Genius use on independent review. Results of the COLO-DETECT trial support the use of GI Genius to increase detection of premalignant colorectal polyps in routine colonoscopy practice. Medtronic.

Preventable predictive factors of post-colonoscopy colorectal cancer in inflammatory bowel disease.

Post-colonoscopy colorectal cancer (PCCRC) is a colorectal cancer (CRC) diagnosed after a colonoscopy in which no cancer is detected (index colonoscopy). Although the overall cumulative rates of PCCRC are low in both the general population and inflammatory bowel disease (IBD) patients, the overall incidence of PCCRC in IBD is greater than that documented in the general population. This study aimed to identify the index colonoscopy-related factors and patients' characteristics influencing IBD-associated PCCRC development. We carried out an observational, retrospective study in which IBD-associated PCCRCs were diagnosed between 2010 and 2023. The PCCRC group was compared to a control cohort of IBD patients without CRC matched 1:1 by several demographic and clinical features as well as characteristics of index colonoscopy to minimize selection bias. Among 61 CRCs identified, 37 (61%) were PCCRC. Twelve of 37 (32%) PCCRC were diagnosed within 12 months after the previous negative colonoscopy, 15 (41%) within 12-36 months, and 10 (27%) within 36-60 months. In the multivariate analysis, the inadequate bowel preparation of the index colonoscopy (OR: 5.9; 95% CI: 11.1- 31.4) and the presence of high-risk factors for CRC (OR: 24.03; 95% CI: 3.1-187.8) were independently associated with PCCRC. Conversely, prior exposure to immunosuppressors/biologics (OR: 0.17; 95% CI: 0.03-0.83) and random biopsies sampling at index colonoscopy (OR:0.19; 95% CI: 0.04-0.85) were inversely associated with PCCRC. More than 50% of CRCs in our population were PCCRC. PCCRCs were associated with previous inadequate cleansing and occurred more frequently in high-risk patients.

Protocol for a national, multicentre study of post-endoscopy colorectal and upper gastrointestinal cancers: The POET study.

The primary aim of the study is to define the post-colonoscopy colorectal cancer (PCCRC) three-year rate and the post-endoscopy upper gastrointestinal cancer (PEUGIC) three-year rate across public hospitals in Aotearoa New Zealand. This retrospective cohort study will be conducted via the trainee-led STRATA Collaborative network. All public hospitals in Aotearoa New Zealand will be eligible to participate. Data will be collected on all adult patients who are diagnosed with colorectal adenocarcinoma within 6 to 48 months of a colonoscopy and all adult patients diagnosed with gastroesophageal cancer within 6 to 48 months of an upper gastrointestinal endoscopy. The study period will be from 2010 to 2022. The primary outcome is the PCCRC 3-year rate and the PEUGIC 3-year rate. Secondary aims are to define and characterize survival after PCCRC or PEUGIC, the cause of PCCRC as based on the World Endoscopy Organization System of Analysis definitions, trends over time, and centre level variation. This protocol describes the methodology for a nationwide retrospective cohort study on PCCRC and PEUGIC in Aotearoa New Zealand. These data will lay the foundation for future studies and quality improvement initiatives.

Association Between Deep Sedation and Risk of Post-colonoscopy Colorectal Cancer: Swedish Register Data 2007-2016

Association Between Deep Sedation and Risk of Post-colonoscopy Colorectal Cancer: Swedish Register Data 2007-2016

Polyp size is associated with colorectal cancer death across histologic polyp subtypes: a retrospective study of a screening colonoscopy registry.

Surveillance colonoscopy after polyps have been detected at screening aims to reduce the risk for subsequent colorectal cancer, so-called post-colonoscopy colorectal cancer (PCCRC). Inconsistencies exist as to whether the risk should be stratified by histologic subtype. We aimed to compare the risk for PCCRC mortality in screening participants with sessile serrated lesions (SSLs)/traditional serrated adenomas (TSAs), hyperplastic polyps (HPPs), or conventional adenomas. Screening colonoscopy registry data were linked to death registry data between 2010 and 2022. We assessed the association of PCCRC death after a diagnosis of SSL/TSA, conventional adenoma, or HPP by Cox regression, and stratified by polyp size ≥10 and <10 mm. 383,801 participants were included in the analysis. There were 1490 HPPs ≥10 mm (2.6%), compared with 1853 SSL/TSAs (19.6%) and 10,960 conventional adenomas (12.9%). When adjusted for polyp location, the association of polyp size ≥10 mm with PCCRC death was of similar magnitude in participants with conventional adenomas (hazard ratio [HR] 3.68, 95%CI 2.49-5.44), SSL/TSAs (HR 2.55, 95%CI 1.13-5.72), and HPPs (HR 5.01, 95%CI 2.45-10.22). Participants with HPPs mostly died of tumors in the distal colon (54.1%; n = 20), while participants with SSL/TSAs more frequently died of proximal tumors (33.3%; n = 3). Across all histologic types, participants with polyps ≥10 mm had at least a two-fold increase in the likelihood of PCCRC death compared with those with polyps <10 mm. These data suggest that size, rather than histologic subtype, should be a determinant for risk stratification after screening colonoscopy.

Quantifying the cost savings and health impacts of improving colonoscopy quality: an economic evaluation

ObjectiveTo estimate and quantify the cost implications and health impacts of improving the performance of English endoscopy services to the optimum quality as defined by postcolonoscopy colorectal cancer (PCCRC) rates.DesignA...

Impact of Bowel Preparation Quality on Colonoscopy Findings and Colorectal Cancer Deaths in a Nation-Wide Colorectal Cancer Screening Program.

Adequate bowel preparation is paramount for a high-quality screening colonoscopy. Despite the importance of adequate bowel preparation, there is a lack of large studies that associated the degree of bowel preparation with long-term colorectal cancer outcomes in screening patients. In a large population-based screening program database in Austria, quality of bowel preparation was estimated according to the Aronchick Scale by the endoscopist (excellent, good, fair, poor, and inadequate bowel preparation). We used logistic regression to assess the influence of bowel preparation on the detection of different polyp types and the interphysician variation in bowel preparation scoring. Time-to-event analyses were performed to investigate the association of bowel preparation with postcolonoscopy colorectal cancer (PCCRC) death. A total of 335,466 colonoscopies between January 2012 and follow-up until December 2022 were eligible for the analyses. As compared with excellent bowel preparation, adenoma detection was not significantly lower for good bowel preparation (odds ratio 1.01, 95% confidence interval [CI] 0.9971-1.0329, P = 0.1023); however, adenoma detection was significantly lower in fair bowel preparation (odds ratio 0.97, 95% CI 0.9408-0.9939, P = 0.0166). Individuals who had fair or lower bowel preparation at screening colonoscopy had significantly higher hazards for PCCRC death (hazard ratio for fair bowel preparation 2.56, 95% CI 1.67-3.94, P < 0.001). Fair bowel preparation on the Aronchick Scale was not only associated with a lower adenoma detection probability but also with increased risk of PCCRC death. Efforts should be made to increase bowel cleansing above fair scores.

Beyond the scope: diverticular disease and post-colonoscopy colorectal cancer.

Beyond the scope: diverticular disease and post-colonoscopy colorectal cancer.