Rupam Bhattacharyya

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.

A randomized controlled trial of pre-procedure simethicone and N-acetylcysteine to improve mucosal visibility during gastroscopy – NICEVIS

Background and study aims: Mucosal views can be impaired by residual bubbles and mucus during gastroscopy. This study aimed to determine whether a pre-gastroscopy drink containing simethicone and N-acetylcysteine improves mucosal visualisation. Patients and methods: We conducted a randomized controlled trial recruiting 126 subjects undergoing routine gastroscopy. Subjects were randomized 1:1:1 to receive: A—pre-procedure drink of water, simethicone and N-acetylcysteine (NAC); B—water alone; or C—no preparation. Study endoscopists were blinded to group allocation. Digital images were taken at 4 locations (lower esophagus/upper gastric body/antrum/fundus), and rated for mucosal visibility (MV) using a 4-point scale (1 = best, 4 = worst) by 4 separate experienced endoscopists. The primary outcome measure was mean mucosal visibility score (MVS). Secondary outcome measures were procedure duration and volume of fluid flush required to achieve adequate mucosal views. Results: Mean MVS for Group A was significantly better than for Group B (1.35 vs 2.11, P < 0.001) and Group C (1.35 vs 2.21, P < 0.001). Mean flush volume required to achieve adequate mucosal views was significantly lower in Group A than Group B (2.0 mL vs 31.5 mL, P = 0.001) and Group C (2.0 mL vs 39.2 mL P < 0.001). Procedure duration did not differ significantly between any of the 3 groups. MV scores at each of the 4 locations demonstrated significantly better mucosal visibility in Group A compared to Group B and Group C (P < 0.0025 for all comparisons). Conclusions: A pre-procedure drink containing simethicone and NAC significantly improves mucosal visibility during gastroscopy and reduces the need for flushes during the procedure. Effectiveness in the lower esophagus demonstrates potential benefit in Barrett’s oesophagus surveillance gastroscopy.

The role of acetic acid in the management of Barrett's oesophagus

Barretts oesophagus is of significant importance due to its premalignant potential. Acetic acid chromoendoscopy is a simple technique that can be used with any endoscope system. It has been utilised for the identification of Barretts intestinal metaplasia; and more importantly, for the localisation of early neoplasia within Barretts, which is often focal, subtle and very easy to miss by random quadrantic biopsies alone. Acetic acid is routinely utilised in specialised centres and its use is expanding. This article examines the evidence base behind acetic acid chromoendoscopy and looks at where further research needs to be directed.

PTH-039 The First Randomised Controlled Trial of Endocuff Vision® Assisted Colonoscopy Versus Standard Colonoscopy for Polyp Detection in Bowel Cancer Screening Patients (E-Cap Study): Abstract PTH-039 Table 1

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).Abstract PTH-039 Table 1 Standard Endocuff No. participants 265 266 No. of polyps 470 436 Polyps/patient 1.77 1.63 Adenomas 364 343 Adenomas/patient 1.37 1.28 Polyp detection rate 185/265 = 69.8% 187/266 = 70.3% Adenoma detection rate 167/265 = 63% 162/266 = 60.9% Cancer detection rate 15/265 = 5.7% 14/266 = 5.3% 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

PWE-108 Feasibility, Safety and Efficacy of Knife Assisted Resection (KAR) of Rectal Polyps Extending to The Dentate Line: How Low Can You Go?

Introduction Rectal polyps extending to the dentate line (RPDL) pose a technical challenge to endoscopic resection due to the narrow lumen, rich venous/haemorrhoidal plexus and proximity to the skin. Conventional snare EMR is challenging due to the restrcited space and lack of precision with the snare. This has led to the use of surgical techniques like TEMS and TAR for resection of RPDLs. Knife Assisted snare Resection (KAR) allows for precise mucosal incision at the dentate line and the dissection of the polyp from the anorectal junction. We aim to assess the feasibility, safety and efficacy of KAR for RPDLs. Methods This is a prospective observational study of patients who underwent KAR with a mean follow up of 32 months (range 1–83 months). All procedures were done on a day case basis and were carried out under sedation by two endoscopists using high definition gastroscopes with a distal transparent cap. The polyp margin on the anal side was injected with lifting solution consisting of gelofusin, indigo carmine, 1% lignocaine and adrenaline. Haemostasis was maintained using a combination of the endoscopic knife and coag-grasper (Olympus Medical). A mucosal incision was extended around the margins of the polyp, followed by submucosal dissection to facilitate snare deployment to achieve complete polyp resection. Post-procedural antibiotics were not routinely given. Results A total of forty patients (20 female, median age 69 years) underwent KAR for RPDLs over the study period. The polyp characteristics and histology are described in Table 1. The curative resection after a single KAR was achieved in 33 (82.5%) patients. 7 of the 40 patients required further KARs, leading to a total curative resection rate to 97%. The risk factors for multiple resections are polyps measuring >60 mm and encompassing >50% of the circumference (p < 0.01). Overall, there was one complication where the patient had delayed bleeding which was managed conservatively. None of the patients experienced perforation, or post-procedural sepsis.Abstract PWE-108 Table 1 Lesion characteristics and histology Lesion size, median (range), mm 50 (12–150) Morphology, n (%) - LST – G, nodular mixed- LST – G, homogenous- LST – NG- Is 29 (72.5)2 (5)2 (5)7 (17.5) Scarring, n (%) 13 (32.5) Histology, n(%) Adenoma with LGDAdenoma with HGDCancerOther – Condyloma acuminatum 30 (75)6 (15)3 (7.5)1 (2.5) Conclusion This is the largest reported series of KAR for RPDLs. Our data demonstrates that for Western endoscopists, KAR is a very safe and effective technique in the treatment of RPDLs. As KAR is a viable alternative to full ESD, TEMS and TAR, it will play an increasingly significant role in the management of RPDLs. Disclosure of Interest None Declared

PTH-032 Knife Assisted Resection of Right-Sided Colonic Polyps: The Right Way Round!: Abstract PTH-032 Table 1

Introduction Endoscopic resection of right-sided colonic polyps carries a higher risk of complications including bleeding and perforation. This risk is heightened in the resection of polyps that are tethered, flat or on background of colitis (complex polyps). In the West, complex polyps in the right colon are frequently managed by endoscopic mucosal resection (EMR) or surgery although recurrence rates can be as high as 20%. Endoscopic submucosal dissection (ESD) is an effective technique in the resection of complex polyps. However, ESD is technically challenging with a long learning curve and carries a significant perforation rate (6% in Eastern series and 17% in Western series) leading to a poor uptake of this technique in the West.[i]We aim to examine the safety and efficacy of a novel technique of knife assisted snare resection (KAR) in resecting complex polyps in the right colon. Methods Data of all KARs undertaken by a single endoscopist in our institution from 2009 to 2015 were prospectively compiled in a pre-designed database and interrogated by independent researchers blinded to the technique. Polyps in the right colon (distal transverse to caecum) were included in the analysis. Polyp characteristics and procedure details were prospectively recorded. Endoscopic follow-up was performed to identify recurrence. Results A total of 52 patients with complex polyps 10–80 mm in size were resected by KAR. The mean follow up time was 35 months. 42% of the polyps were >40 mm in size, and 51% were scarred from previous attempts. The majority of the polyps resected (91%) exhibited flat morphology (Paris Classification IIa, IIa+IIb, IIa+IIc). Table 1 shows the patient baseline and lesion characteristics. There were 2 cases of delayed bleeding (4%) neither of which required surgery. The endoscopic cure rate was 96% after single procedure, improving to 98% with further attempts.Abstract PTH-032 Table 1 Patient baseline and lesion characteristics Age years, (mean) 46-83 (70) Sex (M:F) 2.7:1 Mean polyp size, mm (range) 35 (7–80) En Bloc Resection, n (%) 24 (45%) Scarring, n (%) 28 (51%) Histology, n• Adenoma• SSP• DALM• Cancer 361234 Conclusion This is the first reported Western series of KAR of complex polyps in the right colon. Our data demonstrates that this novel technique is safe and effective for resection of complex polyps in the right colon. The recurrence rates are superior to EMR and complication rates are lower than ESD. As the learning curve for KAR is shorter than that for ESD, we believe that this technique is ideal for the Western setting. Reference 1 Saito Y, Uraoka T, Yamaguchi Y, et al. A prospective, multicenter study of 1111 colorectal endoscopic submucosal dissections. Gastrointest Endosc. 2010;72:1217–1225 Disclosure of Interest None Declared

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

PTU-003 Flexible endoscopic diverticulotomy is a safe and viable treatment for zenker’s diverticulum: a video case series

Introduction Zenker’s diverticulum is a sac-like outpouching of the mucosa and submucosa through an area of muscular weakness between the thyropharyngeus and cricopharyngeus muscles. Traditional treatments have been surgical with open or intraluminal approaches to cricopharyngeal myotomy where the overall complication rate is 9.6%. An alternative approach is to use a flexible endoscope to perform a diverticulotomy. We present a video series to illustrate the principles of flexible endoscopic diverticulotomy. Method We reviewed prospectively collected data of patients with Zenker’s diverticulum referred to our department for endotherapy between January 2014 and January 2015. All patients had Zenker’s diverticulum confirmed on barium swallow. Every procedure was carried out under general anaesthesia by a single endoscopist (PB). A guide wire is inserted into the stomach under direct vision, over which a double-lipped overtube (ZD overtube, ZDO-22–30; Cook Endoscopy, Winston-Salem, North Carolina) is threaded. Under direct vision, the overtube is advanced until the long flap is positioned in the oesophageal lumen and the short flap is in the diverticulum. The septum is clearly visualised and stabilised between the two flaps. The septal mucosa is cut in the middle using a needle knife or diathermy scissors. The mucosal incision is extended until the cricopharyngeal muscle fibres are completely incised. Following this, the cut is extended to approximately 1 cm from the base. Prophylactic endoclips are placed to prevent perforation or bleeding. Patients resume a liquid diet 12 h post procedure. Results A total of 5 patients underwent flexible endoscopic diverticulotomy [female 3, median age 76 years (range 69–84 years)]. 2 patients had previous failed surgical interventions. The mean size of diverticulae was 48 mm (range 30–70 mm) and the mean duration of each procedure was 33 min (range 30–40 mins). 1 patient required an overnight stay as he lived outside our catchment area. There were no procedure related complications or mortality. All patients were able to drink within 12 h and start on a soft diet within 48 h post procedure. Prior to the diverticulotomy, 80% of patients experienced dysphagia with every meal and 60% suffered with regurgitation several times a week. All patients were asymptomatic at follow up at 3. Where 12-month data is available, all patients (3/5) remain asymptomatic. Conclusion In expert hands, flexible endoscopic diverticulotomy is a novel, and safe treatment for Zenker’s diverticulum. It obviates the need for invasive surgery and a majority of patients can be treated on a day-case basis. Initial results are encouraging with no reported complications and excellent short-term success rates. Disclosure of interest None Declared.

PTU-001 Polyps at difficult and high risk location: video series to ilustrate the principles of assessment and resection

Introduction One of the factors which make the removal of a polyp challenging is its location in the GI tract. We will present a series of video clips of polyps located in difficult locations to demonstrate the challenges facing the endoscopist and discuss the strategies to circumvent the problem. Three types of polyps are discussed in this abstract: 1. Polyps involving the dentate line 2. Polyps involving the ileo-caecal valve and terminal ileum and 3. Polyps involving the appendiceal orifice. Method Information regarding the nature, location, procedure, recurrence, complication and need for surgery was obtained from a prospective database of polyps more than 2 cm removed between 2010 and 2014. Results 1. Polyp involving the dentate line: Access to these polyps is very difficult. A rich sensory supply of the distal squamous epithelium, difficulty in identifying the distal edge of the polyp and the rich vascular supply in this region makes it challenging. Twelve cases [n = 12] underwent endoscopic resection. The size ranged from 12 mm–150 mm occupying 25% to 80% of the circumference. Laterally spreading tumour –Granular [n = 10] and two were sessile [1s and 1s/2c, n = 2]. 1. Polyp involving the ileo –caecal valve. Here the challenges include difficult access, identifying the margins, ileal extension and risk of perforation. Seven polyps, 30 mm–60 mm in size and involving the ileo- caecal valves were removed endoscopically. LST –G [5], 1s [1] and SSA [1]. 1. Polyp involving the appendicular orifice Decision to resect these polyps should be weighed against the risk of perforation since these polyps could extend into the appendicular canal. Nine cases of polyp involving the appendicular orifice were resected endoscopically with size ranging from 20 mm -100 mm. Six were LST –G[[7]sessile polyp [2]. Histology of the resected polyps was as follows. TVA with LGD [21], TVA with foci of HGD [2], sessile serrated adenoma [4], tubular adenoma with intra mucosal cancer [1], Tubular adenoma [1]. Conclusion Polyps located at the appendicular orifice and ileo -caecal valve have traditionally been managed with right hemicolectomy and polyps at the dentate line with TAR/TEMS. Our data shows that an expert endoscopist can resect these polyps with good clearance and avoid surgery. This makes a case for referral of these polyps to an expert centre. Disclosure of interest None Declared.Abstract PTU-001 Table 1 Dentate line [n = 12] Ileo-caecal valve [n = 7] Appendicular orifice [n = 9] Hybrid ESD /ESD 8/4 3 1 EMR 4 8 Awaiting follow up 3/12 1/7 0 Curative resection at first attempt 7/9 [77%] 2/6 [33%] 7/9 [77%] Overall curative resection 8/9 [88%] 5/6 [83%] 7/9 [77%] Recurrence requiring multiple attempts 1/9 [11%] 3/6 [50%] 2/9 [22%] Surgery 0 0 1 Complications 2 [16%]bleeding 1 [14%] bleeding 1 [14%] bleeding