Diagnostic yield from symptomatic gastroscopy in the UK: British Society of Gastroenterology analysis using data from the National Endoscopy Database.

OBJECTIVE: This national analysis aimed to calculate the diagnostic yield from gastroscopy for common symptoms, guiding improved resource utilisation. DESIGN: A cross-sectional study was conducted of diagnostic gastroscopies between 1 March 2019 and 29 February 2020 using the UK National Endoscopy Database. Mixed-effect logistic regression models were used, incorporating random (endoscopist) and fixed (symptoms, age and sex) effects on two dependent variables (endoscopic cancer; Barrett's oesophagus (BO) diagnosis). Adjusted positive predictive values (aPPVs) were calculated. RESULTS: 382 370 diagnostic gastroscopies were analysed; 30.4% were performed in patients aged <50 and 57.7% on female patients. The overall unadjusted PPV for cancer was 1.0% (males 1.7%; females 0.6%, p<0.01). Other major pathology was found in 9.1% of procedures, whereas 89.9% reported only normal findings or minor pathology (92.5% in females; 94.6% in patients <50).Highest cancer aPPVs were reached in the over 50s (1.3%), in those with dysphagia (3.0%) or weight loss plus another symptom (1.4%). Cancer aPPVs for all other symptoms were below 1%, and for those under 50, remained below 1% regardless of symptom. Overall, 73.7% of gastroscopies were carried out in patient groups where aPPV cancer was <1%.The overall unadjusted PPV for BO was 4.1% (males 6.1%; females 2.7%, p<0.01). The aPPV for BO for reflux was 5.8% and ranged from 3.2% to 4.0% for other symptoms. CONCLUSIONS: Cancer yield was highest in elderly male patients, and those over 50 with dysphagia. Three-quarters of all gastroscopies were performed on patients whose cancer risk was <1%, suggesting inefficient resource utilisation.

Risk factors for metachronous colorectal cancer or advanced lesions after endoscopic resection of serrated polyps: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Serrated polyps (SPs) are precursors to 15% to 20% of colorectal cancers (CRCs). However, there are uncertainties regarding which SPs require surveillance and at what intervals, with recommendations adapted from those for adenomas in the absence of solid evidence. Our aim was to assess which SP risk characteristics relate to a higher risk of metachronous CRC or advanced polyps. METHODS: We systematically searched PubMed, Embase, and Cochrane for cohort studies, case-control studies, and clinical trials from inception to December 31, 2023, of CRC or advanced polyps (advanced adenoma [AA] or advanced SP) incidence at surveillance stratified by baseline SP size, dysplasia, location, and multiplicity. We defined advanced SPs as those ≥10 mm or with dysplasia. CRC and advanced polyp incidence per 1000 person-years were estimated. We performed a meta-analysis by calculating pooled relative risks (RRs) using a random-effects model. RESULTS: A total of 5903 studies were reviewed, and 14 were included with 493,949 patients (mean age, 59.5 years; 55% men). The mean follow-up was 4.9 years. CRC incidence per 1000 person-years was 2.09 (95% confidence interval [CI], 1.29-2.90) for advanced SPs, 1.52 (95% CI, 0.78-2.25) for SPs of ≥10 mm, 5.86 (95% CI, 2.16-9.56) for SPs with dysplasia, 1.18 (95% CI, 0.77-1.60) for proximal SPs, 0.52 (95% CI, 0.08-1.12) for ≥3 SPs, 0.50 (95% CI, 0.35-0.66) for nonadvanced SPs, and 0.44 (95% CI, 0.41-0.46) for normal colonoscopy findings. Metachronous CRC risk was higher in advanced SPs versus nonadvanced SPs (RR, 1.84; 95% CI, 1.11-3.04) and versus normal colonoscopy findings (RR, 2.92; 95% CI, 2.26-3.77), in SPs of ≥10 mm versus <10 mm (RR, 2.61; 95% CI, 1.43-4.77) and versus normal colonoscopy findings (RR: 3.52; 95% CI, 2.17-5.69); and in SPs with dysplasia versus normal colonoscopy findings (RR: 2.71; 95% CI, 2.00-3.67). No increase in CRC or advanced polyp risk was found in patients with proximal versus distal SPs, nor in ≥3 SPs versus 1 or 2 SPs. CONCLUSIONS: CRC risk is significantly higher in patients with baseline advanced SPs after 4.9 years of follow-up, with risk magnitudes similar to those described for AA, supporting the current recommendation for 3-year surveillance in patients with advanced SPs.

Initiatives to increase colonoscopy capacity - is there an impact on polyp detection? A UK National Endoscopy Database analysis.

BACKGROUND: To address mismatch between routine endoscopy capacity and demand, centers often implement initiatives to increase capacity, such as weekend working or using locums/agency staff (insourcing). However, there are concerns that such initiatives may negatively impact quality. We investigated polyp detection for weekend vs. weekday and insourced vs. standard procedures using data from the UK National Endoscopy Database. METHODS: We conducted a national, retrospective, cross-sectional study of diagnostic colonoscopies performed during 01/01-04/04/2019. The primary outcome was mean number of polyps (MNP) and the secondary outcome was polyp detection rate (PDR). Multi-level mixed-effect regression, fitting endoscopist as a random effect, was used to examine associations between procedure day (weekend/weekday) and type (insourced/standard) and these outcomes, adjusting for patient age, sex, and indication. RESULTS: 92 879 colonoscopies (weekends: 19 977 [21.5 %]; insourced: 9909 [10.7 %]) were performed by 2496 endoscopists. For weekend colonoscopies, patients were less often male or undergoing screening-related procedures; for insourced colonoscopies, patients were younger and less often undergoing screening-related procedures (all P < 0.05). Fully adjusted MNP was significantly lower for weekend vs. weekday (incidence rate ratio [IRR] 0.86 [95 %CI 0.83-0.89]) and for insourced vs. standard procedures (IRR 0.91 [95 %CI 0.87-0.95]). MNP was highest for weekday standard procedures and lowest for weekend insourced procedures; there was no interaction between procedure day and type. Similar associations were found for PDR. CONCLUSIONS: Strategies to increase colonoscopy capacity may negatively impact polyp detection and should be monitored for quality. Reasons for this unwarranted variation require investigation.

Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024.

1: ESGE recommends cold snare polypectomy (CSP), to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of diminutive polyps (≤ 5 mm).Strong recommendation, high quality of evidence. 2: ESGE recommends against the use of cold biopsy forceps excision because of its high rate of incomplete resection.Strong recommendation, moderate quality of evidence. 3: ESGE recommends CSP, to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of small polyps (6-9 mm).Strong recommendation, high quality of evidence. 4: ESGE recommends hot snare polypectomy for the removal of nonpedunculated adenomatous polyps of 10-19 mm in size.Strong recommendation, high quality of evidence. 5: ESGE recommends conventional (diathermy-based) endoscopic mucosal resection (EMR) for large (≥ 20 mm) nonpedunculated adenomatous polyps (LNPCPs).Strong recommendation, high quality of evidence. 6: ESGE suggests that underwater EMR can be considered an alternative to conventional hot EMR for the treatment of adenomatous LNPCPs.Weak recommendation, moderate quality of evidence. 7: Endoscopic submucosal dissection (ESD) may also be suggested as an alternative for removal of LNPCPs of ≥ 20 mm in selected cases and in high-volume centers.Weak recommendation, low quality evidence. 8: ESGE recommends that, after piecemeal EMR of LNPCPs by hot snare, the resection margins should be treated by thermal ablation using snare-tip soft coagulation to prevent adenoma recurrence.Strong recommendation, high quality of evidence. 9: ESGE recommends (piecemeal) cold snare polypectomy or cold EMR for SSLs of all sizes without suspected dysplasia.Strong recommendation, moderate quality of evidence. 10: ESGE recommends prophylactic endoscopic clip closure of the mucosal defect after EMR of LNPCPs in the right colon to reduce to reduce the risk of delayed bleeding.Strong recommendation, high quality of evidence. 11: ESGE recommends that en bloc resection techniques, such as en bloc EMR, ESD, endoscopic intermuscular dissection, endoscopic full-thickness resection, or surgery should be the techniques of choice in cases with suspected superficial invasive carcinoma, which otherwise cannot be removed en bloc by standard polypectomy or EMR.Strong recommendation, moderate quality of evidence.

Adenoma characteristics in the English Bowel Cancer Screening Programme.

AIM: The English Bowel Cancer Screening Programme detects colorectal cancers and premalignant polyps in a faecal occult blood test-positive population. The aim of this work is to describe the detection rates and characteristics of adenomas within the programme, identify predictive factors influencing the presence or absence of carcinoma within adenomas and identify the factors predicting the presence of advanced colonic neoplasia in different colon segments. METHOD: The Bowel Cancer Screening System was retrospectively searched for polyps detected during colonoscopies between June 2006 and June 2012, at which time a guaiac test was being used. Data on size, location and histological features were collected, and described. Univariate and multivariate analyses were used to determine the significant factors influencing the development of carcinoma within an adenoma. RESULTS: A total of 229 419 polyps were identified; after exclusions 136 973 adenomas from 58 334 patients were evaluated. Over half were in the rectum or sigmoid colon. Subcentimetre adenomas accounted for 69.8% of the total. The proportion of adenomas containing advanced histological features increased with increasing adenoma size up to 35 mm, then plateaued. A focus of carcinoma was found in 2282 (1.7%) adenomas, of which 95.6% were located distally. Carcinoma was identified even in diminutive adenomas (0.1%). The proportion of adenomas containing cancer was significantly higher in women than men (2.0% vs. 1.5%, p < 0.001). CONCLUSION: This national, prospectively captured dataset adds robust information about histological features of adenomas that convey an increased risk for colorectal cancer, and identifies caecal adenomas, high-grade dysplasia, increasing adenoma size, distal location and female sex as independent risk factors associated with carcinoma.

Risk Factors for Metachronous Colorectal Cancer or Advanced Adenomas After Endoscopic Resection of High-risk Adenomas.

BACKGROUND & AIMS: Among the characteristics of high-risk adenomas (HRAs), some may predict a higher risk of metachronous advanced lesions. Our aim was to assess which HRA characteristics are associated with high risk of metachronous colorectal cancer (CRC) or advanced adenomas (AAs). METHODS: We systematically searched Pubmed, EMBASE, and Cochrane for cohort studies and clinical trials of CRC or AA incidence at surveillance stratified by baseline lesion size, histology, and multiplicity. We calculated pooled relative risks (RRs) using a random-effects model. Heterogeneity was assessed with the I2 statistic. RESULTS: Fifty-five studies were included, with 936,540 patients with mean follow-up 5.4 ± 2.9 years. CRC incidence per 1000 person-years was 2.6 (2.1-3.0) for adenomas ≥20 mm, 2.7 (2.2-3.2) for high-grade dysplasia (HGD), 2.0 (1.8-2.3) for villous component, 0.8 (0.1-1.4) for ≥5 adenomas, 1.0 (0.7-1.2) for ≥3 adenomas. Metachronous CRC risk was higher in adenomas ≥20 mm vs 10 to 19 mm (RR, 2.08; 95% confidence interval [CI], 1.20-3.61), HGD vs low-grade dysplasia (RR, 2.89; 95% CI, 1.88-4.44), villous vs tubular (RR, 1.75; 95% CI, 1.33-2.31). No significant differences in CRC risk were found in ≥3 adenomas vs 1 to 2 (RR, 1.24; 95% CI, 0.84-1.83), nor in ≥5 adenomas vs 3 to 4 (RR, 0.79; 95% CI, 0.30-2.11). Compared with normal colonoscopy, RR for CRC risk was 2.61 (95% CI, 2.06-3.32) for ≥10mm, 6.62 (95% CI, 4.60-9.52) for HGD, 3.58 (95% CI, 2.24-5.73) for villous component, and 2.03 (95% CI, 1.40-2.94) for ≥3 adenomas. Similar trends were seen for metachronous AAs. CONCLUSION: Metachronous CRC risk is highest in patients with baseline adenomas with ≥20 mm or HGD. Multiplicity does not seem to be associated with substantially higher CRC risk in the near term.

Colorectal cancer and advanced adenoma incidence during post-polypectomy surveillance: a national cohort study in the English Bowel Cancer Screening Programme.

BACKGROUND: Improved colonoscopy quality has led to debate about whether all post-polypectomy surveillance is justified. We evaluated surveillance within the English Bowel Cancer Screening Programme (BCSP) to determine the yield of surveillance and identify predictive factors for surveillance outcome. METHODS: We performed a retrospective cohort study of individuals undergoing post-polypectomy surveillance between July 2006 and January 2017. BCSP records were linked to the National Cancer Registration Database to identify interval-type post-colonoscopy colorectal cancers (CRCs). Advanced adenoma and CRC at surveillance were documented. CRC incidence was compared with the general population using standardized incidence ratios (SIRs). Predictors of advanced adenomas at first surveillance (S1), and CRC during follow-up, were identified. RESULTS: 44 151 individuals (23 078 intermediate risk; 21 073 high risk) underwent 64 544 surveillance episodes. Advanced adenoma and CRC yields were, respectively, 10.0 % and 0.5 % at S1, 8.5 % and 0.4 % at S2, and 10.8 % and 0.4 % at S3. S1 yield was lowest in those with one index adenoma ≥ 10 mm (advanced adenoma 6.1 %; CRC 0.3 %). The SIR was 0.76 (95 %CI 0.66-0.88), accounted for by the intermediate risk group (intermediate risk SIR 0.61, 95 %CI 0.49-0.75; high risk SIR 0.95, 95 %CI 0.79-1.15). Adenoma multiplicity, presence of a large nonpedunculated adenoma, and greater villous component were associated with advanced adenoma at S1. Older age and multiplicity were significantly associated with CRC risk. CONCLUSION: This large, national analysis found low levels of CRC in those undergoing surveillance and low advanced adenoma yield in most subgroups. Less intensive surveillance in some subgroups is warranted, and surveillance may be avoided in those with a single large adenoma.

Third Asia-Pacific consensus recommendations on colorectal cancer screening and postpolypectomy surveillance.

The Asia-Pacific region has the largest number of cases of colorectal cancer (CRC) and one of the highest levels of mortality due to this condition in the world. Since the publishing of two consensus recommendations in 2008 and 2015, significant advancements have been made in our knowledge of epidemiology, pathology and the natural history of the adenoma-carcinoma progression. Based on the most updated epidemiological and clinical studies in this region, considering literature from international studies, and adopting the modified Delphi process, the Asia-Pacific Working Group on Colorectal Cancer Screening has updated and revised their recommendations on (1) screening methods and preferred strategies; (2) age for starting and terminating screening for CRC; (3) screening for individuals with a family history of CRC or advanced adenoma; (4) surveillance for those with adenomas; (5) screening and surveillance for sessile serrated lesions and (6) quality assurance of screening programmes. Thirteen countries/regions in the Asia-Pacific region were represented in this exercise. International advisors from North America and Europe were invited to participate.

Utilization and reproducibility of World Endoscopy Organization post-colonoscopy colorectal cancer algorithms: retrospective analysis.

BACKGROUND: Colorectal cancer (CRC) diagnosed following a cancer-negative colonoscopy is termed post-colonoscopy CRC (PCCRC). In addition to calculating PCCRC rates, the World Endoscopy Organization (WEO) recommends review of individual PCCRC cases, including categorization into interval/non-interval PCCRCs, and root cause analysis to determine the most plausible explanation. We aimed to test the usability, reproducibility, and outcomes of the WEO algorithms. METHODS: All CRC cases diagnosed from January 2015 to December 2016 in a single organization were cross referenced with local endoscopy and pathology databases to identify cases of PCCRC. We assessed: 1) WEO most plausible explanation for PCCRC; and 2) WEO PCCRC interval/non-interval subtype categorization. Interobserver agreement was measured using Cohen's kappa (κ). Cases with interobserver variation underwent panel discussion to reach consensus. RESULTS: Among 527 patients with CRC, 48 PCCRCs were identified. A consistent most plausible explanation was found in 97 % of cases, showing almost perfect agreement (κ = 0.94). Most PCCRCs (66 %) were attributed to "possible missed lesion, prior examination adequate." Interval/non-interval categorization was consistent in 77 %, showing substantial agreement (κ = 0.67). Following panel discussion, consensus was reached in all cases. Overall, 15 % were categorized as interval and 85 % as non-interval PCCRCs (12 % type A, 31 % type B, and 42 % type C). CONCLUSIONS: Review of PCCRC cases using WEO recommendations was performed accurately at a local level using readily available clinical information. The high number of non-interval type B PCCRCs suggests a significant proportion of PCCRCs could be avoided by better adherence to recommended surveillance intervals.

Post-polypectomy surveillance interval and advanced neoplasia detection rates: a multicenter, retrospective cohort study.

BACKGROUND: Longer post-polypectomy surveillance intervals are associated with increased colorectal neoplasia detection at surveillance in some studies. We investigated this association to inform optimal surveillance intervals. METHODS: Patients who underwent colonoscopy and post-polypectomy surveillance at 17 UK hospitals were classified as low/high risk by baseline findings. We compared detection rates of advanced adenomas (≥ 10 mm, tubulovillous/villous, high grade dysplasia), high risk findings (HRFs: ≥ 2 serrated polyps/[adenomas] of which ≥ 1 is ≥ 10 mm or has [high grade] dysplasia; ≥ 5 serrated polyps/adenomas; or ≥ 1 nonpedunculated polyp ≥ 20 mm), or colorectal cancer (CRC) at surveillance colonoscopy by surveillance interval (< 18 months, 2, 3, 4, 5, 6 years). Risk ratios (RRs) were estimated using multivariable regression. RESULTS: Of 11 214 patients, 7216 (64 %) were low risk and 3998 (36 %) were high risk. Among low risk patients, advanced adenoma, HRF, and CRC detection rates at first surveillance were 7.8 %, 3.7 %, and 1.1 %, respectively. Advanced adenoma detection increased with increasing surveillance interval, reaching 9.8 % with a 6-year interval (P trend < 0.001). Among high risk patients, advanced adenoma, HRF, and CRC detection rates at first surveillance were 15.3 %, 10.0 %, and 1.5 %, respectively. Advanced adenoma and CRC detection rates (P trends < 0.001) increased with increasing surveillance interval; RRs (95 % confidence intervals) for CRC were 1.54 (0.68-3.48), 4.44 (1.95-10.08), and 5.80 (2.51-13.40) with 3-, 4-, and 5-year intervals, respectively, versus an interval of < 18 months. CONCLUSIONS: Metachronous neoplasia was uncommon among low risk patients, even with long surveillance intervals, supporting recommendations for no surveillance in these patients. For high risk patients, a 3-year surveillance interval would ensure timely CRC detection.

Performance measures for colonoscopy in inflammatory bowel disease patients: European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative.

The European Society of Gastrointestinal Endoscopy (ESGE) presents a short list of performance measures for colonoscopy in inflammatory bowel disease (IBD) patients. Current performance measures for colonoscopy mainly focus on detecting (pre)malignant lesions. However, these performance measures are not relevant for all colonoscopy indications in IBD patients. Therefore, our aim was to provide endoscopy services across Europe and other interested countries with a tool for quality monitoring and improvement in IBD colonoscopy. Eight key performance measures and one minor performance measure were recommended for measurement and evaluation in daily endoscopy practice.

Performance measures for the SACRED team-centered approach to advanced gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative.

The European Society of Gastrointestinal Endoscopy and United European Gastroenterology have defined performance measures for upper and lower gastrointestinal, pancreaticobiliary, and small-bowel endoscopy. Quality indicators to guide endoscopists in the growing field of advanced endoscopy are also underway. We propose that equal attention is given to developing the entire advanced endoscopy team and not the individual endoscopist alone.We suggest that the practice of teams intending to deliver high quality advanced endoscopy is underpinned by six crucial principles concerning: selection, acceptance, complications, reconnaissance, envelopment, and documentation (SACRED).

Definition of competence standards for optical diagnosis of diminutive colorectal polyps: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement.

BACKGROUND : The European Society of Gastrointestinal Endoscopy (ESGE) has developed a core curriculum for high quality optical diagnosis training for practice across Europe. The development of easy-to-measure competence standards for optical diagnosis can optimize clinical decision-making in endoscopy. This manuscript represents an official Position Statement of the ESGE aiming to define simple, safe, and easy-to-measure competence standards for endoscopists and artificial intelligence systems performing optical diagnosis of diminutive colorectal polyps (1 - 5 mm). METHODS : A panel of European experts in optical diagnosis participated in a modified Delphi process to reach consensus on Simple Optical Diagnosis Accuracy (SODA) competence standards for implementation of the optical diagnosis strategy for diminutive colorectal polyps. In order to assess the clinical benefits and harms of implementing optical diagnosis with different competence standards, a systematic literature search was performed. This was complemented with the results from a recently performed simulation study that provides guidance for setting alternative competence standards for optical diagnosis. Proposed competence standards were based on literature search and simulation study results. Competence standards were accepted if at least 80 % agreement was reached after a maximum of three voting rounds. RECOMMENDATION 1: In order to implement the leave-in-situ strategy for diminutive colorectal lesions (1-5 mm), it is clinically acceptable if, during real-time colonoscopy, at least 90 % sensitivity and 80 % specificity is achieved for high confidence endoscopic characterization of colorectal neoplasia of 1-5 mm in the rectosigmoid. Histopathology is used as the gold standard.Level of agreement 95 %. RECOMMENDATION 2: In order to implement the resect-and-discard strategy for diminutive colorectal lesions (1-5 mm), it is clinically acceptable if, during real-time colonoscopy, at least 80 % sensitivity and 80 % specificity is achieved for high confidence endoscopic characterization of colorectal neoplasia of 1-5 mm. Histopathology is used as the gold standard.Level of agreement 100 %. CONCLUSION : The developed SODA competence standards define diagnostic performance thresholds in relation to clinical consequences, for training and for use when auditing the optical diagnosis of diminutive colorectal polyps.

Expected value of artificial intelligence in gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement.

This ESGE Position Statement defines the expected value of artificial intelligence (AI) for the diagnosis and management of gastrointestinal neoplasia within the framework of the performance measures already defined by ESGE. This is based on the clinical relevance of the expected task and the preliminary evidence regarding artificial intelligence in artificial or clinical settings. MAIN RECOMMENDATIONS:: (1) For acceptance of AI in assessment of completeness of upper GI endoscopy, the adequate level of mucosal inspection with AI should be comparable to that assessed by experienced endoscopists. (2) For acceptance of AI in assessment of completeness of upper GI endoscopy, automated recognition and photodocumentation of relevant anatomical landmarks should be obtained in ≥90% of the procedures. (3) For acceptance of AI in the detection of Barrett's high grade intraepithelial neoplasia or cancer, the AI-assisted detection rate for suspicious lesions for targeted biopsies should be comparable to that of experienced endoscopists with or without advanced imaging techniques. (4) For acceptance of AI in the management of Barrett's neoplasia, AI-assisted selection of lesions amenable to endoscopic resection should be comparable to that of experienced endoscopists. (5) For acceptance of AI in the diagnosis of gastric precancerous conditions, AI-assisted diagnosis of atrophy and intestinal metaplasia should be comparable to that provided by the established biopsy protocol, including the estimation of extent, and consequent allocation to the correct endoscopic surveillance interval. (6) For acceptance of artificial intelligence for automated lesion detection in small-bowel capsule endoscopy (SBCE), the performance of AI-assisted reading should be comparable to that of experienced endoscopists for lesion detection, without increasing but possibly reducing the reading time of the operator. (7) For acceptance of AI in the detection of colorectal polyps, the AI-assisted adenoma detection rate should be comparable to that of experienced endoscopists. (8) For acceptance of AI optical diagnosis (computer-aided diagnosis [CADx]) of diminutive polyps (≤5 mm), AI-assisted characterization should match performance standards for implementing resect-and-discard and diagnose-and-leave strategies. (9) For acceptance of AI in the management of polyps ≥ 6 mm, AI-assisted characterization should be comparable to that of experienced endoscopists in selecting lesions amenable to endoscopic resection.

Impact of the COVID-19 pandemic on UK endoscopic activity and cancer detection: a National Endoscopy Database Analysis.

OBJECTIVE: The COVID-19 pandemic has had a major global impact on endoscopic services. This reduced capacity, along with public reluctance to undergo endoscopy during the pandemic, might result in excess mortality from delayed cancer diagnosis. Using the UK's National Endoscopy Database (NED), we performed the first national analysis of the impact of the pandemic on endoscopy services and endoscopic cancer diagnosis. DESIGN: We developed a NED COVID-19 module incorporating procedure-level data on all endoscopic procedures. Three periods were designated: pre-COVID (6 January 2020 to 15 March), transition (16-22 March) and COVID-impacted (23 March-31 May). National, regional and procedure-specific analyses were performed. The average weekly number of cancers, proportion of missing cancers and cancer detection rates were calculated. RESULTS: A weekly average of 35 478 endoscopy procedures were performed in the pre-COVID period. Activity in the COVID-impacted period reduced to 12% of pre-COVID levels; at its low point, activity was only 5%, recovering to 20% of pre-COVID activity by study end. Although more selective vetting significantly increased the per-procedure cancer detection rate (pre-COVID 1.91%; COVID-impacted 6.61%; p<0.001), the weekly number of cancers detected decreased by 58%. The proportion of missing cancers ranged from 19% (pancreatobiliary) to 72% (colorectal). CONCLUSION: This national analysis demonstrates the remarkable impact that the pandemic has had on endoscopic services, which has resulted in a substantial and concerning reduction in cancer detection. Major, urgent efforts are required to restore endoscopy capacity to prevent an impending cancer healthcare crisis.

Colorectal cancer risk following polypectomy in a multicentre, retrospective, cohort study: an evaluation of the 2020 UK post-polypectomy surveillance guidelines.

OBJECTIVE: Colonoscopy surveillance aims to reduce colorectal cancer (CRC) incidence after polypectomy. The 2020 UK guidelines recommend surveillance at 3 years for 'high-risk' patients with ≥2 premalignant polyps (PMPs), of which ≥1 is 'advanced' (serrated polyp (or adenoma) ≥10 mm or with (high-grade) dysplasia); ≥5 PMPs; or ≥1 non-pedunculated polyp ≥20 mm; 'low-risk' patients without these findings are instead encouraged to participate in population-based CRC screening. We examined the appropriateness of these risk classification criteria and recommendations. DESIGN: Retrospective analysis of patients who underwent colonoscopy and polypectomy mostly between 2000 and 2010 at 17 UK hospitals, followed-up through 2017. We examined CRC incidence by baseline characteristics, risk group and number of surveillance visits using Cox regression, and compared incidence with that in the general population using standardised incidence ratios (SIRs). RESULTS: Among 21 318 patients, 368 CRCs occurred during follow-up (median: 10.1 years). Baseline CRC risk factors included age ≥55 years, ≥2 PMPs, adenomas with tubulovillous/villous/unknown histology or high-grade dysplasia, proximal polyps and a baseline visit spanning 2-90 days. Compared with the general population, CRC incidence without surveillance was higher among those with adenomas with high-grade dysplasia (SIR 1.74, 95% CI 1.21 to 2.42) or ≥2 PMPs, of which ≥1 was advanced (1.39, 1.09 to 1.75). For low-risk (71%) and high-risk (29%) patients, SIRs without surveillance were 0.75 (95% CI 0.63 to 0.88) and 1.30 (1.03 to 1.62), respectively; for high-risk patients after first surveillance, the SIR was 1.22 (0.91 to 1.60). CONCLUSION: These guidelines accurately classify post-polypectomy patients into those at high risk, for whom one surveillance colonoscopy appears appropriate, and those at low risk who can be managed by non-invasive screening.

WASh multicentre randomised controlled trial: water-assisted sigmoidoscopy in English NHS bowel scope screening.

OBJECTIVES: The English Bowel Cancer Screening Programme invites 55 year olds for a sigmoidoscopy (Bowel Scope Screening (BSS)), aiming to resect premalignant polyps, thus reducing cancer incidence. A national patient survey indicated higher procedural pain than anticipated, potentially impacting on screening compliance and effectiveness. We aimed to assess whether water-assisted sigmoidoscopy (WAS), as opposed to standard CO2 technique, improved procedural pain and detection of adenomatous polyps. DESIGN: The WASh (Water-Assisted Sigmoidoscopy) trial was a multicentre, single-blind, randomised control trial for people undergoing BSS. Participants were randomised to either receive WAS or CO2 from five sites across England. The primary outcome measure was patient-reported moderate/severe pain, as assessed by patients on a standard Likert scale post procedure prior to discharge. The key secondary outcome was adenoma detection rate (ADR). The costs of each technique were also measured. RESULTS: 1123 participants (50% women, mean age 55) were randomised (561 WAS, 562 CO2). We found no difference in patient-reported moderate/severe pain between WAS and CO2 (14% in WAS, 15% in CO2; p=0.47). ADR was 15% in the CO2 arm and 11% in the WAS arm (p=0.03); however, it remained above the minimum national performance standard in both arms. There was no statistical difference in mean number of adenomas nor overall polyp detection rate. There was negligible cost difference between the two techniques. CONCLUSION: In the context of enema-prepared unsedated screening sigmoidoscopies performed by screening-accredited endoscopists, no difference in patient-reported pain was seen when using either a CO2 or WAS intubation technique. TRIAL REGISTRATION NUMBER: ISRCTN81466870.

When and How To Use Endoscopic Tattooing in the Colon: An International Delphi Agreement.

BACKGROUND & AIMS: There is a lack of clinical studies to establish indications and methodology for tattooing, therefore technique and practice of tattooing is very variable. We aimed to establish a consensus on the indications and appropriate techniques for colonic tattoo through a modified Delphi process. METHODS: The baseline questionnaire was classified into 3 areas: where tattooing should not be used (1 domain, 6 questions), where tattooing should be used (4 domains, 20 questions), and how to perform tattooing (1 domain 20 questions). A total of 29 experts participated in the 3 rounds of the Delphi process. RESULTS: A total of 15 statements were approved. The statements that achieved the highest agreement were as follows: tattooing should always be used after endoscopic resection of a lesion with suspicion of submucosal invasion (agreement score, 4.59; degree of consensus, 97%). For a colorectal lesion that is left in situ but considered suitable for endoscopic resection, tattooing may be used if the lesion is considered difficult to detect at a subsequent endoscopy (agreement score, 4.62; degree of consensus, 100%). A tattoo should never be injected directly into or underneath a lesion that might be removed endoscopically at a later point in time (agreement score, 4.79; degree of consensus, 97%). Details of the tattoo injection should be stated clearly in the endoscopy report (agreement score, 4.76; degree of consensus, 100%). CONCLUSIONS: This expert consensus has developed different statements about where tattooing should not be used, when it should be used, and how that should be done.

Overcoming the barriers to dissemination and implementation of quality measures for gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) and United European Gastroenterology (UEG) position statement.

The European Society of Gastrointestinal Endoscopy (ESGE) has developed performance measures and established a framework for quality assessment for gastrointestinal endoscopy in Europe. Most national societies actively undertake initiatives to implement and explicitly endorse these quality indicators. Given this, ESGE proposes that, at a national level, strong leadership should exist to disseminate and implement quality parameters. Thus, understanding the potential barriers that may vary locally is of paramount importance. ESGE suggests that each national society should prioritize quality and standards of care in gastrointestinal endoscopy in their activities and should survey/understand which measures are a local priority to their members and make measuring quality intrinsic to daily endoscopy practice.

BowelScope: Accuracy of Detection Using Endocuff Optimisation of Mucosal Abnormalities (the B-ADENOMA Study): a multicentre, randomised controlled flexible sigmoidoscopy trial.

OBJECTIVES: Adenoma detection rate (ADR) is an important quality marker at lower GI endoscopy. Higher ADRs are associated with lower postcolonoscopy colorectal cancer rates. The English flexible sigmoidoscopy (FS) screening programme (BowelScope), offers a one-off FS to individuals aged 55 years. However, variation in ADR exists. Large studies have demonstrated improved ADR using Endocuff Vision (EV) within colonoscopy screening, but there are no studies within FS. We sought to test the effect of EV on ADR in a national FS screening population. DESIGN: BowelScope: Accuracy of Detection Using ENdocuff Optimisation of Mucosal Abnormalities was a multicentre, randomised controlled trial involving 16 English BowelScope screening centres. Individuals were randomised to Endocuff Vision-assisted BowelScope (EAB) or Standard BowelScope (SB). ADR, polyp detection rate (PDR), mean adenomas per procedure (MAP), polyp characteristics and location, participant experience, procedural time and adverse events were measured. Comparison of ADR within the trial with national BowelScope ADR was also undertaken. RESULTS: 3222 participants were randomised (53% male) to receive EAB (n=1610) or SB (n=1612). Baseline demographics were comparable between arms. ADR in the EAB arm was 13.3% and that in the SB arm was 12.2% (p=0.353). No statistically significant differences were found in PDR, MAP, polyp characteristics or location, participant experience, complications or procedural characteristics. ADR in the SB control arm was 3.1% higher than the national ADR. CONCLUSION: EV did not improve BowelScope ADR when compared with SB. ADR in both arms was higher than the national ADR. Where detection rates are already high, EV is unable to improve detection further. TRIAL REGISTRATION NUMBERS: NCT03072472, ISRCTN30005319 and CPMS ID 33224.