Fergus Chedgy

Knife-assisted snare resection: a novel technique for resection of scarred polyps in the colon.

BACKGROUND AND STUDY AIMS There have been significant advances in the management of complex colorectal polyps. Previous failed resection or polyp recurrence is associated with significant fibrosis, making endoscopic resection extremely challenging; the traditional approach to these lesions is surgery. The aim of this study was to evaluate the efficacy of a novel, knife-assisted snare resection (KAR) technique in the resection of scarred colonic polyps. PATIENTS AND METHODS This was a prospective cohort study of patients, in whom the KAR technique was used to resect scarred colonic polyps > 2  cm in size. Patients had previously undergone endoscopic mucosal resection (EMR) and developed recurrence, or EMR had been attempted but was aborted as a result of technical difficulty. RESULTS A total of 42 patients underwent KAR of large (median 40  mm) scarred polyps. Surgery for benign disease was avoided in 38 of 41 patients (93 %). No life-threatening complications occurred. Recurrence was seen in six patients (16 %), five of whom underwent further endoscopic resection. The overall cure rate for KAR in complex scarred colonic polyps was 90 %. CONCLUSIONS KAR of scarred colonic polyps by an expert endoscopist was an effective and safe technique with low recurrence rates.

Knife-assisted snare resection (KAR) of large and refractory colonic polyps at a Western centre: Feasibility, safety and efficacy study to guide future practice.

Objective Endoscopic mucosal resection (EMR) is widely practiced in western countries. Endoscopic submucosal dissection (ESD) is very effective for treating complex polyps but colonic ESD in the western setting remains challenging. We have developed a novel technique of knife-assisted snare resection (KAR) for the resection of these complex lesions. Here we aim to describe the technique, evaluate its outcomes, identify outcome predictors and define its learning curve. Methods We conducted a prospective cohort study of patients who had large and refractory polyps resected by KAR at our institution from 2007 to 2013. Polyp characteristics and procedure details were recorded. Endoscopic follow-up was performed to identify recurrence. Results A total of 170 patients with polyps 20–170 mm in size were treated by KAR and followed up for a mean of 31.5 months (range 12–84 months). 29% of the polyps were >50 mm, 22% had fibrosis from previous unsuccessful interventions and 25% were in the right colon. The perforation rate (1.2%) and bleeding rate (4.7%) were acceptable and managed conservatively in most patients. Recurrence rate after the first attempt was 13.1%. Recurrence was significantly increased by polyp size >50 mm (p = 0.008; OR 5.03, 95% CI 1.54–16.48), presence of fibrosis (p = 0.002; OR 6.59, 95% CI 1.97–22.07) and piecemeal resection (p < 0.001; OR 0.31, CI 0.078–1.12). Cure rates were 87% after the first attempt, improving to 95.6% with further attempts. En bloc resection rate showed a linear increase and reached almost 80% as the endoscopist’s cumulative experience approached 100 cases. Conclusion This is the largest reported Western series on KAR in the colon. We have demonstrated the feasibility, efficacy and safety of this technique in the treatment of complex polyps, with or without fibrosis and at all sites. KAR has shown better outcomes than either EMR or ESD. We have also managed to identify significant outcome predictors and define the learning curve.

International development and validation of a classification system for the identification of Barrett’s neoplasia using acetic acid chromoendoscopy: the Portsmouth acetic acid classification (PREDICT)

Background Barrett’s oesophagus is an established risk factor for developing oesophageal adenocarcinoma. However, Barrett’s neoplasia can be subtle and difficult to identify. Acetic acid chromoendoscopy (AAC) is a simple technique that has been demonstrated to highlight neoplastic areas but lesion recognition with AAC remains a challenge, thereby hampering its widespread use. Objective To develop and validate a simple classification system to identify Barrett’s neoplasia using AAC. Design The study was conducted in four phases: phase 1—development of component descriptive criteria; phase 2—development of a classification system; phase 3—validation of the classification system by endoscopists; and phase 4—validation of the classification system by non-endoscopists. Results Phases 1 and 2 led to the development of a simplified AAC classification system based on two criteria: focal loss of acetowhitening and surface patterns of Barrett’s mucosa. In phase 3, the application of PREDICT (Portsmouth acetic acid classification) by endoscopists improved the sensitivity and negative predictive value (NPV) from 79.3% and 80.2% to 98.1% and 97.4%, respectively (p<0.001). In phase 4, the application of PREDICT by non-endoscopists improved the sensitivity and NPV from 69.6% and 75.5% to 95.9% and 96.0%, respectively (p<0.001). Conclusion We developed and validated a classification system known as PREDICT for the diagnosis of Barrett’s neoplasia using AAC. The improvement seen in the sensitivity and NPV for detection of Barrett’s neoplasia in phase 3 demonstrates the clinical value of PREDICT and the similar improvement seen among non-endoscopists demonstrates the potential for generalisation of PREDICT once proven in real time.

Early squamous neoplasia of the esophagus: The endoscopic approach to diagnosis and management

Considerable focus has been placed on esophageal adenocarcinoma in the last 10 years because of its rising incidence in the West. However, squamous cell cancer (SCC) continues to be the most common type of esophageal cancer in the rest of the world. The detection of esophageal SCC (ESCC) in its early stages can lead to early endoscopic resection and cure. The increased incidence of ESCC in high-risk groups, such as patients with head and neck squamous cancers, highlights the need for screening programs. Lugols iodine chromoendoscopy remains the gold standard technique in detecting early ESCC, however, safer techniques such as electronic enhancement or virtual chromoendoscopy would be ideal. In addition to early detection, these new “push-button” technological advancements can help characterize early ESCC, thereby further aiding the diagnostic accuracy and facilitating resection. Endoscopic resection (ER) of early ESCC with negligible risk of lymph node metastases has been widely accepted as an effective therapeutic strategy because it offers similar success rates when compared to esophagectomy, but carries lesser morbidity and mortality. Endoscopic submucosal dissection (ESD) is the preferred technique of ER in lesions larger than 15 mm because it provides higher rates of en bloc resections and lower local recurrence rates when compared to endoscopic mucosal resection (EMR).

Advances in the endoscopic diagnosis and treatment of Barrett's neoplasia.

Barrett’s oesophagus is a well-recognised precursor of oesophageal adenocarcinoma. The incidence of oesophageal adenocarcinoma is continuing to rise in the Western world with dismal survival rates. In recent years, efforts have been made to diagnose Barrett’s earlier and improve surveillance techniques in order to pick up cancerous changes earlier. Recent advances in endoscopic therapy for early Barrett’s cancers have shifted the paradigm away from oesophagectomy and have yielded excellent results.

Attitudes to out-of-programme experiences, research and academic training of gastroenterology trainees between 2007 and 2016

Objective Academic medical training was overhauled in 2005 after the Walport report and Modernising Medical Careers to create a more attractive and transparent training pathway. In 2007 and 2016, national web-based surveys of gastroenterology trainees were undertaken to determine experiences, perceptions of and perceived barriers to out-of-programme research experience (OOP-R). Design, setting and patients Prospective, national web-based surveys of UK gastroenterology trainees in 2007 and 2016. Main outcome measure Attitudes to OOP-R of two cohorts of gastroenterology trainees. Results Response rates were lower in 2016 (25.8% vs 56.7%) (p<0.0001), although female trainees’ response rates increased (from 28.8% to 37.6%) (p=0.17), along with higher numbers of academic trainees. Over 80% of trainees planned to undertake OOP-R in both surveys, with >50% having already undertaken it. Doctor of Philosophy/medical doctorate remained the most popular OOP-R in both cohorts. Successful fellowship applications increased in 2016, and evidence of gender inequality in 2007 was no longer evident in 2016. In the 2016 cohort, 91.1% (n=144) felt the development of trainee-led research networks was important, with 74.7% (n=118) keen to get involved. Conclusions The majority of gastroenterology trainees who responded expressed a desire to undertake OOP-R, and participation rates in OOP-R remain high. Despite smaller absolute numbers responding than in 2007, 2016 trainees achieved higher successful fellowship application rates. Reassuringly more trainees in 2016 felt that OOP-R would be important in the future. Efforts are needed to tackle potential barriers to OOP-R and support trainees to pursue research-active careers.

Acetic acid-guided biopsies in Barrett’s surveillance for neoplasia detection versus non-targeted biopsies (Seattle protocol): A feasibility study for a randomized tandem endoscopy trial. The ABBA study

Background and study aims  Barrett’s esophagus is a potentially pre-cancerous condition, affecting 375,000 people in the UK. Patients receive a 2-yearly endoscopy to detect cancerous changes, as early detection and treatment results in better outcomes. Current treatment requires random mapping biopsies along the length of Barrett’s, in addition to biopsy of visible abnormalities. As only 13 % of pre-cancerous changes appear as visible nodules or abnormalities, areas of dysplasia are often missed. Acetic acid chromoendoscopy (AAC) has been shown to improve detection of pre-cancerous and cancerous tissue in observational studies, but no randomized controlled trials (RCTs) have been performed to date. Patients and methods  A “tandem” endoscopy cross-over design. Participants will be randomized to endoscopy using mapping biopsies or AAC, in which dilute acetic acid is sprayed onto the surface of the esophagus, highlighting tissue through an whitening reaction and enhancing visibility of areas with cellular changes for biopsy. After 4 to 10 weeks, participants will undergo a repeat endoscopy, using the second method. Rates of recruitment and retention will be assessed, in addition to the estimated dysplasia detection rate, effectiveness of the endoscopist training program, and rates of adverse events (AEs). Qualitative interviews will explore participant and endoscopist acceptability of study design and delivery, and the acceptability of switching endoscopic techniques for Barretts surveillance. Results  Endoscopists’ ability to diagnose dysplasia in Barrett’s esophagus can be improved. AAC may offer a simple, universally applicable, easily-acquired technique to improve detection, affording patients earlier diagnosis and treatment, reducing endoscopy time and pathology costs. The ABBA study will determine whether a crossover “tandem” endoscopy design is feasible and acceptable to patients and clinicians and gather outcome data to power a definitive trial.

Knife-assisted resection of flat dysplastic lesions in colitis

The risk of colonic neoplasia is increased in inflammatory bowel disease. Flat dysplastic lesions in colitis can be difficult to detect and challenging to resect endoscopically. Conventional EMR has been used, but because these lesions are often flat morphologically, the snare slips off. Endoscopic submucosal dissection (ESD) has been shown to be able to resect flat lesions; however, they carry a high perforation rate outside the rectum. Knife-assisted snare resection (KAR) is a novel technique that combines the principles of EMR and ESD. We evaluate the safety and efficacy of this technique in resecting flat dysplastic lesions in colitis, and we demonstrate the technique in Video 1. The data pertaining to all KARs undertaken by a single endoscopist in our institution from 2012 to 2014 were prospectively compiled in a predesigned database. Two independent researchers interrogated the database.

Tu2087 The first randomised controlled trial of Endocuff Vision® assisted colonoscopy versus standard colonoscopy for polyp detection in bowel cancer screening patients (E-CAP study)

Introduction Up to 25% polyps are missed during colonoscopy. The Endocuff Vision® is a cap with soft flexible arms that attaches to the colonoscope tip and improves views during withdrawal. We have performed the first randomised controlled trial to identify the role of Endocuff Vision® in improving polyp detection. We aim to investigate the impact of Endocuff Vision® assisted colonoscopy on polyp detection, as compared to standard colonoscopy, in the UK Bowel Cancer Screening Programme (BCSP). Methods Single centre, parallel group, randomised controlled trial. Ethics ref: 14/SC/0207. Adopted on UKCRN portfolio (ID: 16985). Patients attending for BCSP colonoscopy were stratified based on attendance for index screening colonoscopy or for polyp surveillance. Within each stratum participants were randomised to either Standard or Endocuff assisted colonoscopy. All procedures were performed by accredited BSCP endoscopists, who have carried out > 5000 colonoscopies and have caecal intubation rates of >90%. Results 534 patients recruited from Sep 2014 to Sep 2015. 3 excluded due to new diagnosis of polyposis syndrome. 531 were included and randomised to the 2 study arms. No significant difference was seen between the 2 groups for the primary endpoint of number of polyps per patient. Secondary endpoints: No significant difference was observed between the 2 groups for adenoma detection rate (ADR) or number of adenomas per patient (Table 1). No significant adverse events were encountered during the study in either arm. The cecal intubation time was not prolonged and patients did not experience any additional discomfort due to the Endocuff Vision. Conclusion In the UK, bowel cancer screening is performed by highly experienced endoscopists. Our results suggest that in expert hands, ADR exceeds 60% even without Endocuff. In such settings, Endocuff Vision did not improve polyp detection rates (PDR) or ADR. However, it did not cause any adverse events, prolong procedure duration or cause additional discomfort. These data demonstrate the safety and feasibility of Endocuff. However, no additional gain was demonstrated in expert hands. Disclosure of Interest None Declared