774 SNARE TIP SOFT COAGULATION OF THE MARGINS OF THE POST ENDOSCOPIC MUCOSAL RESECTION (EMR) DEFECTS: A QUALITY IMPROVEMENT PROJECT IN PREVENTION OF ADENOMA RECURRENCE

Abstract

Endoscopic mucosal resection is safe and effective technique for removal of large colorectal polyps (>20mm). Adenoma recurrence is one of the main limitations of EMR, which up to 20-55% recurrence occurs on first surveillance colonoscopy warranting systematic follow up program. Invisible microscopic adenoma at EMR site might be the cause of adenoma recurrence on follow up. Thermal ablation or burning of the margins with snare tip may eradicate the invisible micro-adenoma and decrease the adenoma recurrence. This was a quality improvement project with a main aim of reducing adenoma recurrence at first surveillance colonoscopy (SC1). This project was started on Nov 2016 with a video demonstration of snare tip soft coagulation of post EMR margins (by prof. Michael Bourke) to all EMR endoscopists at our hospital. All patients who were referred for EMR of large colorectal polyps (>20mm) were eligible for inclusion. After the polyp and visible adenoma islands were removed with standard technique; margins of post EMR defect was treated with snare tip soft coagulation using Olympus ESG at 20-80W. All five endoscopists with an extensive experience in EMR technique were involved. First surveillance colonoscopy was performed at 3-6 months with a biopsy of post EMR scar base. All the available STSC cases were compared with the consecutive EMR cases done prior to Nov 2016 matching with lesion size (as controls). Over median follow up of 6 months; 54 patients with STSC had completed first surveillance colonoscopy (SC1). Forty three percent were male, median age was 66 years, and median polyp size was 25mm. There were no differences between two groups (STSC vs non-STSC) in terms of age, sex, size of polyps, polyp histology, APC use, initial EMR site, adverse events, and procedure characteristics between EMR endoscopists except median follow up time. Adenoma recurrence in STSC group is significantly lower than non-STSC group (13% vs 32%, p=0.01) Table 1. Coagulation or burning of post EMR margins with snare tip significantly decreases adenoma recurrence. Implementation of this simple technique in routine practice may decrease the patient morbidity associated with frequent surveillance, and increase the EMR efficiency.Tabled 1Baseline characteristics and adenoma recurrence between STSC vs non-STSC groupVariablesSTSC=54Non-STSC=57P-valueAge, median (range)66 (49-81)67 (45-83)0.7aSex, Male (%)24 (43%)29 (52%)0.4bSize of polyp(mm), Median(range), mean (SD)25 (20-60), 28 (11)25 (20-60), 28 (11)0.9cFollow up, Median (range)6 (1-8)7 (3-28)0.01a**Site of polyp resection0.9bProximal Colon45 (83)47 (82)Distal Colon9 (17)10 (18)Polyp histology0.3bSessile serrated adenoma (SSA)25 (46)17 (30)Sessile serrated adenoma with HGD (SSA with HGD)1 (2)0 (0)Tubular adenoma (TA)13 (24)21 (37)Tubular adenoma with HGD (TA with HGD)2 (4)2 (4)Tubulovillous adenoma (TVA)9 (17)15 (26)Tubulovillous adenoma with HGD (TVA with HGD)2 (4)1 (2)Intramucosal carcinoma1 (2)1 (2)APC0 (0)2 (4)0.1bEndoscopists at initial EMR0.1bEndoscopists 123 (44)18 (32)Endoscopists 214 (23)10 (18)Endoscopists 35 (10)14 (25)Endoscopists 45 (10)5 (9)Endoscopists 55 (10)9 (16)Adverse Events0 (0)0 (0)-Adenoma Recurrence7 (13)18 (32)0.01b**Relative risk (95% CI)0.3 (0.11-0.82)3.1 (1.21-8.67)0.02**HGD: high grade dysplasia; EMR: endoscopic mucosal resection, SD: Standard deviation; non-STSC: no snare tip soft coagulation, STSC: Snare tip soft coagulation, a: Wilcoxon rank sums test; b: Chi Square test; c= Pair T-test; CI: Confidence Interval. Open table in a new tab