Outcomes of complex colorectal polyps managed by multi-disciplinary team strategies-a multi-centre observational study.

PURPOSE: Team management strategies for complex colorectal polyps are recommended by professional guidelines. Multi-disciplinary meetings are used across the UK with limited information regarding their impact. The aim of this multi-centre observational study was to assess procedures and outcomes of patients managed using these approaches. METHOD: This was a retrospective, observational study of patients managed by six UK sites. Information was collected regarding procedures and outcomes including length of stay, adverse events, readmissions and cancers. RESULTS: Two thousand one hundred ninety-two complex polyps in 2109 patients were analysed with increasing referrals annually. Most presented symptomatically and the mean polyp size was 32.1 mm. Primary interventions included endoscopic therapy (75.6%), conservative management (8.3%), colonic resection (8.1%), trans-anal surgery (6.8%) or combined procedures (1.1%). The number of primary colonic resections decreased over the study period without a reciprocal increase in secondary procedures or recurrence. Secondary procedures were required in 7.8%. The median length of stay for endoscopic procedures was 0 days with 77.5% completed as day cases. Median length of stay was 5 days for colonic resections. Overall adverse event and 30-day readmission rates were 9.0% and 3.3% respectively. Malignancy was identified in 8.8%. Benign polyp recurrence occurred in 13.1% with a median follow up of 30.4 months. Screening detected lesions were more likely to undergo bowel resection. Colonic resection was associated with longer stays, higher adverse events and more cancers on final histology. CONCLUSION: Multi-disciplinary team management of complex polyps is safe and effective. Standardisation of organisation and quality monitoring is needed to continue positive effects on outcomes and services.

Persistent viral shedding of SARS-CoV-2 in faeces - a rapid review.

AIM: In addition to respiratory symptoms, COVID-19 can present with gastrointestinal complaints suggesting possible faeco-oral transmission. The primary aim of this review was to establish the incidence and timing of positive faecal samples for SARS-CoV-2 in patients with COVID-19. METHODS: A systematic literature review identified studies describing COVID-19 patients tested for faecal virus. Search terms for MEDLINE included 'clinical', 'faeces', 'gastrointestinal secretions', 'stool', 'COVID-19', 'SARS-CoV-2' and '2019-nCoV'. Additional searches were done in the American Journal of Gastroenterology, Gastroenterology, Gut, Lancet Gastroenterology and Hepatology, the World Health Organization Database, the Centre for Evidence-Based Medicine, New England Journal of Medicine, social media and the National Institute for Health and Care Excellence, bioRxiv and medRxiv preprints. Data were extracted concerning the type of test, number and timing of positive samples, incidence of positive faecal tests after negative nasopharyngeal swabs and evidence of viable faecal virus or faeco-oral transmission of the virus. RESULTS: Twenty-six relevant articles were identified. Combining study results demonstrated that 53.9% of those tested for faecal RNA were positive. The duration of faecal viral shedding ranged from 1 to 33 days after a negative nasopharyngeal swab with one result remaining positive 47 days after onset of symptoms. There is insufficient evidence to suggest that COVID-19 is transmitted via faecally shed virus. CONCLUSION: There is a high rate of positive polymerase chain reaction tests with persistence of SARS-CoV-2 in faecal samples of patients with COVID-19. Further research is needed to confirm if this virus is viable and the degree of transmission through the faeco-oral route. This may have important implications on isolation, recommended precautions and protective equipment for interventional procedures involving the gastrointestinal tract.

Antibiotic exposure and the risk of colorectal adenoma and carcinoma: a systematic review and meta-analysis of observational studies.

AIM: The Incidence of colorectal cancer (CRC) is increasing, and evidence suggests that maladaptation of the bowel microbiome may be associated with colorectal carcinogenesis. Consumption of antibiotics may cause imbalance of the bowel microbiome but research assessing an association between antibiotic exposure and CRC is inconsistent. The aim of this systematic review and meta-analysis was to appraise and synthesize the available evidence. METHOD: The MEDLINE, EMBASE and CINAHL databases were searched for published observational studies. We included eight studies of 3 408 312 patients. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the odds of CRC following antibiotic exposure were estimated. Sensitivity analyses were performed according to exposure definition, study design and risk of bias. RESULTS: A weak association between antibiotic exposure and CRC was demonstrated when exposure was assessed cumulatively by the number of prescriptions (OR 1.204, 95% CI 1.097-1.322, P < 0.001) or duration of antibiotic exposure (OR 1.168, 95% CI 1.087-1.256, P < 0.001). Antibiotic exposure assessed as a binary variable demonstrated no association with CRC. CONCLUSION: The findings suggest a weak association between cumulative antibiotic consumption and risk of CRC but no causal conclusions can be made. Limitations include the heterogeneity and quality of the available research, particularly with regard to measurement of antibiotic exposure.

Variations in the management of significant polyps and early colorectal cancer: results from a multicentre observational study of 383 patients.

AIM: The concept of significant polyps and early colorectal cancer (SPECC) encompasses complex polyps not amenable to routine snare polypectomy or where malignancy cannot be excluded. Surgical resection (SR) offers definitive treatment, but is overtreatment for the majority which are benign and amenable to less invasive endoscopic resection (ER). The aim of this study was to investigate variations in the management and outcomes of significant colorectal polyps. METHOD: This was a retrospective observational study of significant colorectal polyps, defined as nonpedunculated lesions of ≥ 20 mm size, diagnosed across nine UK hospitals in 2014. Inclusion criteria were endoscopically or histologically benign polyps at biopsy. RESULTS: A total of 383 patients were treated by primary ER (87.2%) or SR (12.8%). Overall, 108/383 (28%) polyps were detected in the Bowel Cancer Screening Programme (BCSP). Primary SR was associated with a significantly longer length of stay and major complications (P < 0.01). Of the ER polyps, 290/334 (86.8%) patients were treated without undergoing surgery. The commonest indication for secondary surgery was unexpected polyp cancer, and of these cases 60% had no residual cancer in the specimen. Incidence of unexpected cancer was 10.7% (n = 41) and was similar between ER and SR groups (P = 0.11). On multivariate analysis, a polyp size of > 30 mm and non-BCSP status were independent risk factors for primary SR [OR 2.51 (95% CI 1.08-5.82), P = 0.03]. CONCLUSION: ER is safe and feasible for treating significant colorectal polyps. Robust accreditation within the BCSP has led to improvements in management, with lower rates of SR compared with non-BCSP patients. Standardization, training in polyp assessment and treatment within a multidisciplinary team may help to select appropriate treatment strategies and improve outcomes.

British Society of Gastroenterology position statement on serrated polyps in the colon and rectum

Serrated polyps have been recognised in the last decade as important premalignant lesions accounting for between 15% and 30% of colorectal cancers. There is therefore a clinical need for guidance on how to manage these lesions; however, the evidence base is limited. A working group was commission by the British Society of Gastroenterology (BSG) Endoscopy section to review the available evidence and develop a position statement to provide clinical guidance until the evidence becomes available to support a formal guideline. The scope of the position statement was wide-ranging and included: evidence that serrated lesions have premalignant potential; detection and resection of serrated lesions; surveillance strategies after detection of serrated lesions; special situations-serrated polyposis syndrome (including surgery) and serrated lesions in colitis; education, audit and benchmarks and research questions. Statements on these issues were proposed where the evidence was deemed sufficient, and re-evaluated modified via a Delphi process until >80% agreement was reached. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool was used to assess the strength of evidence and strength of recommendation for finalised statements. Key recommendation: we suggest that until further evidence on the efficacy or otherwise of surveillance are published, patients with sessile serrated lesions (SSLs) that appear associated with a higher risk of future neoplasia or colorectal cancer (SSLs ≥10 mm or serrated lesions harbouring dysplasia including traditional serrated adenomas) should be offered a one-off colonoscopic surveillance examination at 3 years (weak recommendation, low quality evidence, 90% agreement).

Report of the Association of Coloproctology of Great Britain and Ireland/British Society of Gastroenterology Colorectal Polyp Working Group: the development of a complex colorectal polyp minimum dataset.

AIM: The management of large non-pedunculated colorectal polyps (LNPCPs) is complex, with widespread variation in management and outcome, even amongst experienced clinicians. Variations in the assessment and decision-making processes are likely to be a major factor in this variability. The creation of a standardized minimum dataset to aid decision-making may therefore result in improved clinical management. METHOD: An official working group of 13 multidisciplinary specialists was appointed by the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the British Society of Gastroenterology (BSG) to develop a minimum dataset on LNPCPs. The literature review used to structure the ACPGBI/BSG guidelines for the management of LNPCPs was used by a steering subcommittee to identify various parameters pertaining to the decision-making processes in the assessment and management of LNPCPs. A modified Delphi consensus process was then used for voting on proposed parameters over multiple voting rounds with at least 80% agreement defined as consensus. The minimum dataset was used in a pilot process to ensure rigidity and usability. RESULTS: A 23-parameter minimum dataset with parameters relating to patient and lesion factors, including six parameters relating to image retrieval, was formulated over four rounds of voting with two pilot processes to test rigidity and usability. CONCLUSION: This paper describes the development of the first reported evidence-based and expert consensus minimum dataset for the management of LNPCPs. It is anticipated that this dataset will allow comprehensive and standardized lesion assessment to improve decision-making in the assessment and management of LNPCPs.

Development of an E-learning System for the Endoscopic Diagnosis of Early Gastric Cancer: An International Multicenter Randomized Controlled Trial.

BACKGROUND: In many countries, gastric cancer is not diagnosed until an advanced stage. An Internet-based e-learning system to improve the ability of endoscopists to diagnose gastric cancer at an early stage was developed and was evaluated for its effectiveness. METHODS: The study was designed as a randomized controlled trial. After receiving a pre-test, participants were randomly allocated to either an e-learning or non-e-learning group. Only those in the e-learning group gained access to the e-learning system. Two months after the pre-test, both groups received a post-test. The primary endpoint was the difference between the two groups regarding the rate of improvement of their test results. FINDINGS: 515 endoscopists from 35 countries were assessed for eligibility, and 332 were enrolled in the study, with 166 allocated to each group. Of these, 151 participants in the e-learning group and 144 in the non-e-learning group were included in the analysis. The mean improvement rate (standard deviation) in the e-learning and non-e-learning groups was 1·24 (0·26) and 1·00 (0·16), respectively (P<0·001). INTERPRETATION: This global study clearly demonstrated the efficacy of an e-learning system to expand knowledge and provide invaluable experience regarding the endoscopic detection of early gastric cancer (R000012039).

British Society of Gastroenterology/Association of Coloproctologists of Great Britain and Ireland guidelines for the management of large non-pedunculated colorectal polyps

These guidelines provide an evidence-based framework for the management of patients with large non-pedunculated colorectal polyps (LNPCPs), in addition to identifying key performance indicators (KPIs) that permit the audit of quality outcomes. These are areas not previously covered by British Society of Gastroenterology (BSG) Guidelines.A National Institute of Health and Care Excellence (NICE) compliant BSG guideline development process was used throughout and the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool was used to structure the guideline development process. A systematic review of literature was conducted for English language articles up to May 2014 concerning the assessment and management of LNPCPs. Quality of evaluated studies was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) Methodology Checklist System. Proposed recommendation statements were evaluated by each member of the Guideline Development Group (GDG) on a scale from 1 (strongly agree) to 5 (strongly disagree) with >80% agreement required for consensus to be reached. Where consensus was not reached a modified Delphi process was used to re-evaluate and modify proposed statements until consensus was reached or the statement discarded. A round table meeting was subsequently held to finalise recommendations and to evaluate the strength of evidence discussed. The GRADE tool was used to assess the strength of evidence and strength of recommendation for finalised statements.KPIs, a training framework and potential research questions for the management of LNPCPs were also developed. It is hoped that these guidelines will improve the assessment and management of LNPCPs.

A novel method for determining the difficulty of colonoscopic polypectomy.

INTRODUCTION: Endoscopists are now expected to perform polypectomy routinely. Colonic polypectomy varies in difficulty, depending on polyp morphology, size, location and access. The measurement of the degree of difficulty of polypectomy, based on polyp characteristics, has not previously been described. OBJECTIVE: To define the level of difficulty of polypectomy. METHODS: Consensus by nine endoscopists regarding parameters that determine the complexity of a polyp was achieved through the Delphi method. The endoscopists then assigned a polyp complexity level to each possible combination of parameters. A scoring system to measure the difficulty level of a polyp was developed and validated by two different expert endoscopists. RESULTS: Through two Delphi rounds, four factors for determining the complexity of a polypectomy were identified: size (S), morphology (M), site (S) and access (A). A scoring system was established, based on size (1-9 points), morphology (1-3 points), site (1-2 points) and access (1-3 points). Four polyp levels (with increasing level of complexity) were identified based on the range of scores obtained: level I (4-5), level II (6-9), level III (10-12) and level IV (>12). There was a high degree of interrater reliability for the polyp scores (interclass correlation coefficient of 0.93) and levels (κ=0.888). CONCLUSIONS: The scoring system is feasible and reliable. Defining polyp complexity levels may be useful for planning training, competency assessment and certification in colonoscopic polypectomy. This may allow for more efficient service delivery and referral pathways.

The WIMAT colonoscopy suitcase model: a novel porcine polypectomy trainer.

AIM: Simulation allows the acquisition of complex skills within a safe environment. Endoscopic polypectomy has a long learning curve. Our novel polypectomy simulator may be a useful adjunct for training. The aim of this study was to assess its content validity. METHOD: The Welsh Institute for Minimal Access Therapy (WIMAT) endoscopy suitcase was designed to simulate colonic polypectomy. Participants from regional and national courses were recruited into the study. Each undertook a standardized simulated polypectomy and completed a seven-point Likert scale questionnaire examining its realism. RESULTS: In all, 17 participants completed the questionnaire: 15 (88.2%) gastroenterologists, one (5.9%) colorectal surgeon and one (5.9%) experienced endoscopic nurse specialist. Of the gastroenterologists, seven (46.7%) were consultants and eight (53.3%) were senior trainees or Post CCT (Certificate of Completion of Training) fellows. The mean number of real-life polypectomies performed by the cohort was 156 (95% CI 35-355). The highest scores were for 'mucosal realism' (median score 6.0, P=0.001), 'endoscopic snare control' (median score 6.0, P=0.001), 'handling the polyp' (median score 6.0, P=0.001) and 'raising mucosa' (median score 6.0, P<0.001). Of the 15 parameters examined only three were not statistically significant in favour of the simulator. These were 'anatomical realism of sessile polyps', 'resistance of scope movement' and 'paradoxical motion'. The overall score for the simulation was 6.0 (P < 0.001). There was no significant difference between the level of difficulty of the simulator compared with real life (median score 4.0, P = 0.559). CONCLUSION: The WIMAT colonoscopy suitcase model has excellent content validity for several parameters. This may have potential applications in medical training and assessment.

Helping the general physician to improve outcomes after PEG insertion: how we changed our practice.

During their careers, most general physicians are involved in the decision-making process for patients that potentially require percutaneous endoscopic gastrostomy (PEG) insertion. However, poor patient selection and less than favourable outcomes are frequently observed in this group. With the aim of identifying and addressing the underlying issues, the PEG service at University Hospital Llandough was radically changed over an eight-year period. The development of a nurse-led pre-assessment service and design of a specific referral form was successful in reducing the number of PEG referrals and consequently the 30-day mortality rate. Furthermore, the educational and training needs of general physicians of all grades regarding the issues surrounding PEG placement were identified and addressed at formal teaching sessions. A combination of these factors has positively impacted on our service, with more appropriate patient selection and a reduced 30-day mortality rate.

Inherited predisposition to colorectal adenomas caused by multiple rare alleles of MUTYH but not OGG1, NUDT1, NTH1 or NEIL 1, 2 or 3.

BACKGROUND: MUTYH-associated polyposis (MAP) is a recessive trait characterised by multiple colorectal adenomas and a high risk of colorectal cancer. MUTYH functions in the DNA base excision repair pathway and has a key role in the repair of oxidative DNA damage. OBJECTIVES: To assess the contribution of inherited variants in genes involved in base excision repair and oxidative DNA damage including MUTYH, OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1 to the multiple colorectal adenoma phenotype. METHODS: Inherited variants of MUTYH, OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1 were sought in 167 unrelated patients with multiple colorectal adenomas whose family histories were consistent with recessive inheritance. These variants were also characterised in approximately 300 population controls. RESULTS: Thirty-three patients (20%) and no controls were MUTYH homozygotes or compound heterozygotes (ie, carried two mutations) and therefore had MAP. Eight different pathogenic MUTYH mutations were identified, of which four were novel. MAP cases had significantly more adenomas than non-MAP cases (p = 0.0009; exact test for trends in proportions) and presented earlier (p = 0.013; analysis of variance). Twenty-four protein-altering variants were identified upon screening of OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1. However, all combinations of two (or more) variants that were identified at an individual locus in patients were also seen in controls, and no variants were significantly over-represented (or under-represented) in cases. CONCLUSION: Multiple rare alleles of MUTYH are associated with autosomal recessive MAP, while OGG1, NEIL1, NEIL2, NEIL3, NUDT1 and NTH1 do not contribute significantly to autosomal recessive polyposis.

MutYH (MYH) and colorectal cancer.

MAP (MutYH-associated polyposis) is a recently described colorectal adenoma and carcinoma predisposition syndrome that is associated with biallelic-inherited mutations of the human MutY homologue gene, MutYH. MutYH is often also termed MYH. MAP tumours display a mutational signature of somatic guanine-to-thymine transversion mutations in the adenomatous polyposis coli and K-ras genes, reflecting the normal role of MutYH in the base excision repair of adenines misincorporated opposite 7,8-dihydro-8-oxoguanine, a prevalent and stable product of oxidative damage to DNA. However, the full genetic pathway of MAP tumorigenesis has not been elucidated.