Complete Polyp Resection Research Articles

Recurrences of advanced sessile and lateral spreading colorectal adenoma after endoscopic mucosal resection (EMR) thermal ablation versus no adjuvant therapy (RESPECT): a protocol of an international randomized controlled trial

BackgroundNowadays, large benign lateral spreading lesions (LSLs) and sessile polyps in the colorectum are mostly resected by endoscopic mucosal resection (EMR). A major drawback of EMR is the polyp recurrence rate of up to 20%. Snare tip soft coagulation (STSC) is considered an effective technique to reduce recurrence rates. However, clinical trials on STSC have mainly been conducted in expert referral centers. In these studies, polyp recurrence was assessed optically, and additional adjunctive techniques were excluded. In the current trial, we will evaluate the efficacy and safety of STSC in daily practice, by allowing adjunctive techniques during EMR and the use of both optical and histological polyp recurrence to assess recurrences during follow-up.MethodsThe RESPECT study is a multicenter, parallel-group, international single blinded randomized controlled superiority trial performed in the Netherlands and Germany. A total of 306 patients undergoing piecemeal EMR for LSLs or sessile colorectal polyps sized 20–60 mm will be randomized during the procedure after endoscopic complete polyp resection to the intervention or control group. Post-EMR defects allocated to the intervention group will be treated with thermal ablation with STSC of the entire resection margin. Primary outcome will be polyp recurrence by optical and histological confirmation at the first surveillance colonoscopy after 6 months. Secondary outcomes include technical success and complication rates.DiscussionThe RESPECT study will evaluate if STSC is effective in reducing recurrence rates after piecemeal EMR of large colorectal lesions in daily clinical practice performed by expert and non-expert endoscopists. Moreover, endoscopists will be allowed to use adjunctive techniques to remove remaining adenomatous tissue during the procedure. Finally, adenomatous polyp recurrence during follow-up will be defined by histologic identification.Trial registrationClinicalTrials.gov NCT05121805. Registered on 16 November 2021. Start recruitment: 17 March 2022. Planned completion of recruitment: 31 April 2025.

COLD SNARE POLYPECTOMY: A SAFE PROCEDURE FOR REMOVING SMALL NON-PEDUNCULATED COLORECTAL LESIONS.

Polypectomy is an important treatment option for preventing colorectal cancer. Incomplete polyp resection (IPR) is re-cognized as a risk factor for interval cancer. The primary objective was to evaluate the complete polyp resection (CPR) rate for cold snare polypectomy (CSP) in small non-pedunculated polyps and, secondarily, specimen retrieval and complication rates. We prospectively evaluated 479 polyps <10 mm removed by CSP in 276 patients by an inexperienced endoscopist. A total of 476 polyps (99.4%) were resected en bloc. A negative margin (classified as CPR) was observed in 435 polyps (90.8%). An unclear or positive margin (classified as IPR) was observed in 43 cases (9.0%) and 1 case (0.2%), respectively, for an overall IPR rate of 9.2% (44/479). The IPR rate was 12.2% in the first half of cases and 5.9% in the second half (P=0.02). Dividing into tertiles, the IPR rate was 15.0% in the first tertile, 6.9% in the second tertile, and 5.7% in the third tertile (P=0.01). Dividing into quartiles, the IPR rate was 15.8% in the first quartile and 5.9% in the fourth quartile (P=0.03). The IPR rate was 6.3% for type 0-IIa lesions and 14.1% for type 0-Is lesions (P=0.01). For serrated and adenomatous lesions, the IPR rate was 9.2%. Specimen retrieval failed in 3.6% of cases. Immediate bleeding (>30 s) occurred in 1 case (0.2%), treated with argon plasma coagulation. No delayed bleeding or perforation occurred. CSP is a safe technique that provides good results for the resection of small non-pedunculated polyps, with a short learning curve.

Performing High-Quality, Safe, Cost-Effective, and Efficient Basic Colonoscopy in 2023: Advice From Two Experts.

Based on published evidence and our expert experience, we provide recommendations to maximize the efficacy, safety, efficiency, and cost-effectiveness of routine colonoscopy. High-quality colonoscopy begins with colon preparation using a split or same-day dose and preferably a low-volume regimen for optimal patient tolerance and compliance. Successful cecal intubation can be achieved by choosing the correct colonoscope and using techniques to facilitate navigation through challenges such as severe angulations and redundant colons. Safety is a primary goal, and complications such as perforation and splenic rupture can be prevented by avoiding pushing through fixed resistance and avoiding loops in proximal colon. Furthermore, barotrauma can be avoided by converting to water filling only (no gas insufflation) in every patient with a narrowed, angulated sigmoid. Optimal polyp detection relies primarily on compulsive attention to inspection as manifested by adequate inspection time, vigorous probing of the spaces between haustral folds, washing and removing residual debris, and achieving full distention. Achieving minimum recommended adenoma detection rate thresholds (30% in men and 20% in women) is mandatory, and colonoscopists should aspire to adenoma detection rate approaching 50% in screening patients. Distal attachments can improve mucosal exposure and increase detection while shortening withdrawal times. Complete resection of polyps complements polyp detection in preventing colorectal cancer. Cold resection is the preferred method for all polyps < 10 mm. For effective cold resection, an adequate rim of normal tissue should be captured in the snare. Finally, cost-effective high-quality colonoscopy requires the procedure not be overused, as demonstrated by following updated United States Multi Society Task Force on Colorectal Cancer postpolypectomy surveillance recommendations.

Cold snare versus cold forceps polypectomy for endoscopic resection of diminutive polyps: meta-analysis of randomized controlled trials.

The practices for resection of diminutive colon polyps vary among endoscopists and US Multi-Society Task force (USMSTF) guidelines recommend use of cold snare polypectomy (CSP) for this purpose. In this meta-analysis, we have compared CSP and cold forceps polypectomy (CFP) for resection of diminutive polyps. We reviewed several databases to identify randomized controlled trials (RCTs) that compared CSP and CFP for resection of diminutive polyps. Our outcomes of interest were complete resection of all diminutive polyps, complete resection of polyps ≤ 3mm in size, failure of tissue retrieval and polypectomy time. For categorical variables, we calculated pooled odds ratios (OR) with 95% confidence intervals (CI); for continuous variables, we calculated mean difference (MD) with 95% CI. Data were analyzed using random effects model and heterogeneity was assessed using the I2 statistic RESULTS: We included 9 studies with 1037 patients. Rate of complete resection of all diminutive polyps was significantly higher in the CSP group, OR (95% CI) 1.68 (1.09, 2.58). Subgroup analysis including jumbo or large capacity forceps, found no significant difference in complete resection between groups, OR (95% CI) 1.43 (0.80, 2.56). We found no significant difference in the rates of complete resection of ≤ 3mm polyps between groups, OR (95% CI) 0.83 (0.30, 2.31). Rate of failure of tissue retrieval was significantly higher in CSP group, OR (95% CI): 10.13 (2.29, 44.74). We found no significant difference in polypectomy time between groups. CFP using large capacity or jumbo biopsy forceps is non-inferior to CSP for complete resection of diminutive polyps.

Endometrial polypectomy using tissue removal device or electrosurgical snare: a randomised controlled trial.

Hysteroscopic transcervical resection of endometrial polyps is a widely used method and is increasingly performed in office or outpatient care. To ensure patient comfort is key, smaller instruments are preferred while also achieving a complete resection of the pathology. To evaluate the effectiveness of the electrosurgical polyp snare (DPS) in comparison with a tissue removal device (TRD). This was a randomised controlled non-inferiority trial which included 66 women with symptomatic endometrial polyps who had been referred to the gynaecological outpatient clinic at the Máxima Medical Centre, Veldhoven, the Netherlands. The patients were randomly allocated by using sealed envelopes to treatment with either the DPS (Duckbill®, Cook) or the TRD (Truclear™, Medtronic). Clinicians and patients were not blinded to the treatment performed. An independent observer blindly assessed the results. The primary outcome was the complete removal of the endometrial polyp. Secondary outcomes were woman acceptability and pain during the procedure, operating time, peri-operative and immediate postoperative complications. 57% of the polyps in the DPS group and 95% in the TRD group were completely removed (risk difference -0.39; 95% CI: -0.60 to -0.15). Average operating time was longer with DPS compared to the TRD (11.7 min. vs. 6.8 min., p = 0.018). The number of insertions of the hysteroscope was higher with the DPS compared to the TRD (3.9 vs. 1.7, p <0.001). One serious adverse event, a uterine perforation, occurred in the DPS group. The TRD was superior to the DPS in completeness of polyp removal. TRD has a higher rate of complete polyp resection, overall safety and higher patient satisfaction, this instrument should be considered as the preferred option in outpatient and office gynaecology.

Recurrence rates after endoscopic resection of large colorectal polyps: A systematic review and meta-analysis.

BACKGROUNDComplete polyp resection is the main goal of endoscopic removal of large colonic polyps. Resection techniques have evolved in recent years and endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR) with margin ablation, cold snare polypectomy (CSP), cold EMR, and underwater EMR have been introduced. Yet, efficacy of these techniques with regard to local recurrence rates (LRRs) vs traditional hot snare polypectomy and standard EMR remains unclear. AIMTo analyze LRR of large colonic polyps in a systematic review and meta-analysis.METHODSMEDLINE, EMBASE, EBM Reviews, and CINAHL were searched for prospective studies reporting LRR or incomplete resection rate (IRR) after colonic polypectomy of polyps ≥ 10 mm, published between January 2011 and July 2021. Primary outcome was LRR for polyps ≥ 10 mm. RESULTSSix thousand nine hundred and twenty-eight publications were identified, of which 34 prospective studies were included. LRR for polyps ≥ 10 mm at up to 12 mo’ follow-up was 11.0% (95%CI, 7.1%-14.8%; 15 studies; 4904 polyps). ESD (1.7%; 95%CI, 0%-3.4%; 3 studies, 221 polyps) and endoscopic mucosal resection with margin ablation (3.3%; 95%CI, 2.2%-4.5%; 2 studies, 947 polyps) significantly reduced LRR vs standard EMR without (15.2%; 95%CI, 12.5%-18.0%; 4 studies, 650 polyps) or with unsystematic margin ablation (16.5%; 95%CI, 15.2%-17.8%; 6 studies, 3031 polyps). CONCLUSIONLRR is significantly lower after ESD or EMR with routine margin ablation; thus, these techniques should be considered standard for endoscopic removal of large colorectal polyps. Other techniques, such as CSP, cold EMR, and underwater EMR require further evaluation in prospective studies before their routine implementation in clinical practice can be recommended.

Comparison of cold snare and hot snare polypectomy for the resection of sporadic nonampullary duodenal adenomas

Nonampullary duodenal adenomas can undergo malignant transformation, making endoscopic resection, often by hot snare (HSP) or cold snare polypectomy (CSP), necessary. Although CSP has been shown to be safer for removal of colon polyps, data comparing these techniques for the resection of duodenal adenomas are limited. Our aim was to compare the safety and efficacy of CSP and HSP for the removal of nonampullary duodenal adenomas. We performed a retrospective cohort study of patients referred to 2 academic medical centers with a histologically confirmed sporadic, nonampullary duodenal adenoma who underwent endoscopic snare polypectomy between January 1, 2007 and March 1, 2021. Patients with underlying polyposis syndromes were excluded. Outcomes included postprocedural adverse events and polyp recurrence. Of 110 total patients, 69 underwent HSP and 41 underwent CSP. Intraprocedural bleeding was similar between both groups, but 7 patients in the HSP group experienced delayed adverse events versus none in the CSP group (P= .04). Fifty-four patients had complete polyp resection and subsequent surveillance endoscopies. Multivariate analysis showed polyp size to be associated with recurrence (permm; odds ratio, 1.11; 95% confidence interval, 1.04-1.20; P< .01). Endoscopic resection technique (HSP vs CSP) was not a predictor of recurrence (P= .18). HSP led to more delayed adverse events compared with CSP, whereas no significant differences on outcomes were noted, suggesting that CSP is equally effective and potentially safer for the removal of duodenal adenomas.

Is underwater endoscopic mucosal resection of colon polyps superior to conventional techniques? A network analysis of endoscopic mucosal resection and submucosal dissection.

Background and study aims Evidence from recent trials comparing conventional endoscopic mucosal resection (EMR) to underwater EMR (UEMR) have matured. However, studies comparing UEMR to endoscopic submucosal dissection (ESD) are lacking. Hence, we sought to conduct a comprehensive network meta-analysis to compare the efficacy of UEMR, ESD, and EMR. Methods Embase and Medline databases were searched from inception to December 2020 for articles comparing UEMR with EMR and ESD. Outcomes of interest included rates of en bloc and complete polyp resection, risk of perforation and bleeding, and local recurrence. A network meta-analysis comparing all three approaches was conducted. In addition, a conventional comparative meta-analysis comparing UEMR to EMR was performed. Analysis was stratified according to polyp sizes (< 10 mm, ≥ 10 mm, and ≥ 20 mm). Results Twenty-two articles were included in this study. For polyps ≥ 10 mm, UEMR was inferior to ESD in achieving en bloc resection ( P = 0.02). However, UEMR had shorter operating time for polyps ≥ 10 mm ( P < 0.001), and ≥20 mm ( P = 0.019) with reduced perforation risk for polyps ≥ 10 mm ( P = 0.05) compared to ESD. In addition, en bloc resection rates were similar between UEMR and EMR, although UEMR had reduced recurrence for polyps ≥ 10 mm ( P = 0.013) and ≥ 20 mm ( P = 0.014). UEMR also had shorter mean operating than EMR for polyps ≥ 10 mm ( P < 0.001) and ≥ 20 mm ( P < 0.001). Risk of bleeding and perforation with UEMR and EMR were similar for polyp of all sizes. Conclusions UEMR has demonstrated technical and oncological outcomes comparable to ESD and EMR, along with a desirable safety profile. UEMR appears to be a safe and effective alternative to conventional methods for resection of polyps ≥ 10 mm.

The quality of colorectal polypectomy. Is it enough to have just a visual assessment of the site?

Introduction: Performing a colonoscopy allows the examination of the entire colon and the assessment of polyps. Patients, Materials and Methods: We performed a retrospective analysis of prospectively collected data from January 2018 until February 2020 (two years), in which we enrolled a number of 210 patients performing colonoscopy in the Research Center of Gastroenterology and Hepatology, University of Medicine and Pharmacy of Craiova, Romania. We performed 326 polypectomies. Results: We classified the polyps into diminutive (n=169), small (n=103) and large polyps (n=54). Regarding the polypectomy technique, our results indicated that 40 out of 48 (83.3%) polypectomies with the biopsy forceps were complete, as well as 27 out of 31 (87.1%) cold snare polypectomies and 12 out of 14 (85.7%) hot snare polypectomies. The differences were not statistically significant (p=0.116). Regarding the number of incomplete polypectomies, our data suggests that the high expertise endoscopist had two incomplete resections (5.1% of total), the medium expertise endoscopist 1 had also two incomplete resections (11.1% of total), the medium expertise endoscopist 2 had three incomplete resections (15% of total), the limited expertise endoscopist 1 had three incomplete resections (27.27% of total) and the limited expertise endoscopist 2 had four incomplete resections (30.76% of total). Analyzing the data, the differences were statistically significant (p=0.006). Conclusions: Our study is able to suggest that high-definition white-light endoscopy (HD–WLE) macroscopic visualization of the polyp resection site is not enough to assess complete polyp resection and follow-up colonoscopy should be performed for cases with incomplete margins of resection.

Mucosal defect size predicts the adequacy of resection of ≤10 mm nonpedunculated colorectal polyps using a new cold snare polypectomy technique.

There is still room for improvement in the methods used to achieve complete polyp resection. The aim of this study was to develop a cold snare polypectomy technique that will reliably result in resections containing the muscularis mucosae and the lateral polyp margins. Nonpedunculated polyps ≤10 mm were resected using a dedicated cold snare with the goal of creating a mucosal defect approximately 1 cm in dia. The completeness of resection of the lateral and vertical polyp margins was examined histologically. The cases of 201 patients (mean age 67 ± 13 years; 115 men) with 500 eligible polyps were enrolled. The mean polyp size was 6.1 ± 1.8 mm (range 1-10 mm). The mean mucosal defect size immediately after resection was 7.7 ± 2.5 mm (range 3-15 mm). Overall, the complete resection rate in which the lateral and vertical margins were free from the neoplasia tissue was 92% (417/454, 95% CI, 89-94); in the remaining 8% of cases, the vertical margins showed complete resection but the lateral margins could not be evaluated due to the fragmentation of resected polyps. A mucosal defect ≥7 mm predicted complete resection of the mucosal layer containing the muscularis mucosae. Complete mucosal layer resection of nonpedunculated colorectal polyps ≤10 mm was reliably achieved using a cold snare technique that produced a mucosal defect ≥7 mm in dia.

Complications of cold versus hot snare polypectomy of 10-20 mm polyps: A retrospective cohort study.

Background and AimCold snare polypectomy is safe and efficacious for removing polyps <10 mm with reduced rates of delayed postpolypectomy bleeding and postpolypectomy syndrome. This technique can also be used for sessile polyps ≥10 mm; however, further evidence is required to establish its safety. The aim of this study was to compare intraprocedure and postprocedure adverse events in patients who underwent cold (CSP) versus hot snare polypectomy (HSP) of 10–20 mm sessile colonic polyps.MethodsElectronic medical records and endoscopy reports of all patients who underwent polypectomy for Paris 0‐IIa, Is, or 0‐IIa + Is 10–20 mm colonic polyps between January 2015 and June 2017 at three tertiary academic hospitals and one private hospital were retrospectively reviewed. Data on patient demographics, polyp characteristics, method of polypectomy, and intraprocedural and postpolypectomy adverse events were collected.ResultsA total of 408 patients (median age 67, 50% male) had 604 polyps, 10–20 mm in size, removed. Of these, 258 polyps were removed by HSP, with a median size of 15 mm (interquartile range [IQR] 12–20), compared to 346 polyps that were removed by CSP, with median size of 12 mm (IQR 10–15), P < 0.001. In the HSP group, 15 patients presented with postprocedure complications, including 11 with clinically significant bleeding, 2 with postpolypectomy syndrome, and 2 with abdominal pain. This compares with no postpolypectomy complications in the CSP group, P < 0.001.ConclusionIn this study, CSP was not associated with any postpolypectomy adverse events. CSP appears to be safer than HSP for removing 10–20 mm‐sized sessile polyps. A prospective multicenter study has been commenced to verify these findings and to assess the efficacy of CSP for the complete resection of polyps of this size.

Hot snare vs. cold snare polypectomy for endoscopic removal of 4 - 10 mm colorectal polyps during colonoscopy: a systematic review and meta-analysis of randomized controlled studies.

Introduction In recent years, cold snare polypectomy (CSP) has increasingly been used over hot snare polypectomy (HSP) for the removal of colorectal polyps (4 – 10 mm in size). However, the optimal technique (CSP vs. HSP), in terms of complete polyp resection and complications, is uncertain. Our aim was to compare incomplete resection rate (IRR) of polyps and complications using CSP vs. HSP. Methods Randomized controlled studies (RCTs) comparing CSP and HSP for removal of 4 – 10 mm colorectal polyps were considered. Studies were included in the analysis if they obtained biopsy specimens from the resection margin to confirm the absence of residual tissue and reported complications. IRR and complication rate were the outcome measures. Pooled rates were reported as Odds Ratios (OR) or risk difference with 95 % Confidence Interval (CI). Results In total, three RCTs were included in the final analysis. A total of 1051 patients with 1485 polyps were randomized to either HSP group (n = 741 polyps) or CSP group (n = 744 polyps). The overall IRR did not differ between the two groups (HSP vs. CSP: 2.4 % vs. 4.7 %; OR 0.51, 95 %CI 0.13 – 1.99, P = 0.33, I 2 = 73 %). The HSP group had a lower rate of overall complications compared to the CSP group (3.7 % vs. 6.6 %; OR 0.53, 95 % CI 0.3 – 0.94, P = 0.03, I 2 = 0 %). Polyp retrieval rates were not different between the two groups (99 % vs. 98.1 %). Conclusion Our results suggest that HSP and CSP techniques can be effectively used for the complete removal of 4 – 10 mm colorectal polyps; however, HSP has a lower incidence of overall complications.

Jumbo biopsy forceps versus cold snares for removing diminutive colorectal polyps: a prospective randomized controlled trial

Cold snare polypectomy (CSP) and jumbo forceps polypectomy (JFP) have been shown to be effective for removing diminutive colorectal polyps (DCPs) (≤5mm). However, no study has compared complete resection rates between CSP and JFP for DCPs. The aim of this study was to compare the efficacy and safety of JFP with CSP for the removal of DCPs. This was a prospective randomized controlled trial from 2 tertiary-care referral centers. A total of 1003 patients were screened, and 169 patients with 196 DCPs were enrolled. The main outcome was complete polyp resection rate. Of 196 diminutive polyps, 177 (90.3%) were adenomatous polyps. The overall complete resection rate was 92.1% (163/177). The complete resection rate was not significantly different between JFP and CSP groups (92.0% vs 92.2%; P= .947). JFP achieved complete resection rates comparable with CSP for polyps >3mm (90.3% vs 89.8%; P= .928). Polypectomy procedure time, tissue retrieval rate, and rate of postpolypectomy adverse events were not significantly different between the 2 groups. Both JFP and CSP achieved complete resection rates of >90% for DCPs. Thus, JFP may be considered forpolypectomy of DCPs. (International clinical trial registry number: KCT0002805.).

Hysteroscopic Endometrial Polypectomy with Manual Vacuum Aspiration Compared to Mechanical Morcellation

To examine the effectiveness of hysteroscopy plus manual vacuum aspiration (MVA) for endometrial polypectomy compared with hysteroscopic morcellation. Retrospective cohort study (Canadian Task Force classification II-2). Duke University Medical Center database. Women who underwent hysteroscopic removal of endometrial polyps performed by Duke Fertility Center faculty physicians between January 1, 2015, and January 29, 2018, using either hysteroscopy plus MVA or hysteroscopic morcellation. The 2 groups were compared using the χ2 or Fisher's exact test, Student's t test, and multivariable regression analysis. The primary outcome was the duration of the procedure. Secondary outcomes were fluid deficit, rate of complete polyp resection, estimated blood loss, and operative complications. A total of 102 women undergoing endometrial polypectomy were identified. Patients in whom polyps were removed using only a hysteroscopic grasper and/or scissors (n = 31); patients who underwent an additional simultaneous procedure, such as laparoscopy (n = 12); and patients in whom the duration of the procedure was not recorded (n = 2) were excluded. Among the remaining 57 patients, 28 underwent hysteroscopy plus MVA and 29 underwent hysteroscopic morcellation. The mean duration of procedure was longer for hysteroscopic morcellation compared with hysteroscopy plus MVA (32 ± 10 minutes vs 20 ± 6 minutes; p = .04), and this difference remained significant after adjusting for age, body mass index, surgeon, and number and size of polyps. Mean fluid deficit was greater for morcellation than for hysteroscopy plus MVA (277 ± 204 mL vs 51 ± 97 mL; p < .001). Complete polyp resection was possible in all patients; however, the use of a hysteroscopic scissors and grasper was required for 1 patient in the MVA group. Estimated blood loss was minimal in all cases, and there were no operative complications. Hysteroscopy plus MVA is an effective method for removing large or multiple endometrial polyps, with outcomes comparable to hysteroscopic morcellation.

Width and depth of resection for small colorectal polyps: hot versus cold snare polypectomy

Curability is associated with resection width and depth in polypectomy. We evaluated the resection width and depth achieved with hot snare polypectomy (HSP) and cold snare polypectomy (CSP) for small colorectal polyps. In this single-center, prospective, randomized controlled study, patients with rectal or rectosigmoid polyps≤10mm in diameter were treated with HSP or CSP. Resection width was evaluated as mucosal defect size, measured immediately postprocedure and 1 day later. Resection depth was histologically evaluated using obtained specimens. Fifty-two patients were enrolled. Mean lesion size was 5.6mm with HSP (n= 27) and 5.8mm with CSP (n= 25). Mean mucosal defect diameter immediately after HSP and CSP was 5.1mm and 7.5mm, respectively (P< .001). The diameter 1 day after the procedure increased by 29% (95% confidence interval [CI], 17%-41%) with HSP and decreased by 25% (95% CI, 18%-32%) with CSP (P< .001). Muscularis mucosa was obtained similarly with HSP and CSP (96% [95% CI, 82%-99%] vs 92% [95% CI, 75%-98%]; P= .603). Submucosal tissuewas obtained significantly more frequently with HSP than with CSP (81% [95% CI, 63%-92%] vs 24% [95% CI, 11%-43%]; P< .001). The resection width immediately after CSP was larger than that after HSP but was significantly smaller at day 1 after resection. Although the resection depth after CSP was more superficial, muscularis mucosa was obtained in most specimens. Thus, CSP has sufficient resection width and depth to enable complete polyp resection and potentially has a superior safety profile than HSP.

A prospective comparison of cold snare polypectomy using traditional or dedicated cold snares for the resection of small sessile colorectal polyps

Background and study aims The evidence for efficacy and safety of cold snare polypectomy is limited. The aim of this study was to assess the completeness of resection and safety of cold snare polypectomy, using either traditional or dedicated cold snares. Patients and methods This was a prospective, non-randomized study performed at a single tertiary hospital. Adult patients with at least one colorectal polyp (size ≤ 10 mm) removed by cold snare were included. In the first phase, all patients had polyps removed by traditional snare without diathermy. In the second phase, all patients had polyps removed by dedicated cold snare. Complete endoscopic resection was determined from histological examination of quadrantic polypectomy margin biopsies. Immediate or delayed bleeding within 2 weeks was recorded. Results In total, 181 patients with 299 eligible polyps (n = 93 (173 polyps) traditional snare group, n = 88 (126 polyps) dedicated cold snare group) were included. Patient demographics and procedure indications were similar between groups. Mean polyp size was 6 mm in both groups ( P = 0.25). Complete polyp resection was 165 /173 (95.4 %; 95 %CI 90.5 – 97.6 %) in the traditional snare group and 124/126 (98.4 %; 95 %CI 93.7 – 99.6 %) in the dedicated cold snare group ( P = 0.16). Serrated polyps, compared with adenomatous polyps, had a higher rate of incomplete resection (7 % vs. 2 %, P = 0.03). There was no statistically significant difference in the rate of immediate bleeding (3 % vs. 1 %, P = 0.41) and there were no delayed hemorrhages or perforations. Conclusions Cold snare polypectomy is effective and safe for the complete endoscopic resection of small (≤ 10 mm) colorectal polyps with either traditional or dedicated cold snares.

Expression of Annexin A10 in Serrated Polyps Predicts the Development of Metachronous Serrated Polyps.

Objectives:The ability to differentiate histological characteristics between serrated polyps (SPs) and make a pathological diagnosis of a sessile serrated polyp (SSP) is highly variable. Recent studies have shown that immunohistochemical (IHC) expression of Annexin A10 (ANXA10) is a marker of a SSP. However, the clinical utility of ANXA10 expression in patients with SPs is unknown. The objective of this study was to evaluate the utility of ANXA10 expression in SPs in predicting the development of subsequent polyps at follow-up colonoscopy.Methods:Specimens from patients with SPs assessed in the Department of Pathology between 2006 and 2010 were identified. Patients whose colon harbored only SPs including either an SSP and/or hyperplastic polyp (HP) and who had complete polyp resection, no remaining polyps, and a follow-up colonoscopy were analyzed. ANXA10 IHC expression was performed in all baseline SPs. The rate of metachronous polyps on follow-up colonoscopy based on baseline maximal ANXA10 expression (low vs. high) was determined.Results:One hundred and seventy-nine patients were included. Sixty-seven patients had SPs with low ANXA10 expression (30 SSP and 37 HP) and 112 had polyps with high ANXA10 expression (105 SSP and 7 with HP). Individuals with SPs with high ANXA10 expression had a threefold higher risk of SSP on follow-up colonoscopy (hazard ratio (HR)=2.7; P=0.048) particularly, in the proximal colon (HR=4.0; P=0.02). ANXA10 expression did not predict patients at an increased risk of subsequent adenomas (18.8% vs. 19.4%, P=0.52).Conclusions:Individuals who harbor SPs with high ANXA10 expression are at an increased risk of metachronous serrated neoplasms. ANXA10 may be a reproducible tool to stratify patients with SPs into higher- and lower-risk groups of metachronous serrated neoplasia, allowing a more aggressive colonoscopic surveillance in patients at high risk.

PWE-108 Feasibility, Safety and Efficacy of Knife Assisted Resection (KAR) of Rectal Polyps Extending to The Dentate Line: How Low Can You Go?: Abstract PWE-108 Table 1

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. K nife A ssisted snare R esection (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 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

Su1651 “Underwater” Endoscopic Mucosal Resection Without Sub-Mucosal Injection for Large Colonic Polyps: A First Look in New Zealand

Endoscopic Mucosal Resection (EMR) has been used in the staging and treatment of superficial neoplasms of the gastrointestinal tract. Sub-mucosal injection is normally used to decrease the risk of perforation. However, this can make complete resection of polyps technically more difficult. A new method of “underwater” EMR (UEMR) eliminates the need for sub-mucosal injection1.

The diminutive colon polyp

Diminutive polyps, measuring between 1 and 5 mm, represent the vast majority of colorectal polyps encountered during screening colonoscopy. Although the chance of harboring advanced adenoma or neoplastic cells is low, ensuring a complete polyp resection with clear margins is crucial to reduce the risk of interval colorectal cancer. The purpose of this review was to evaluate the different methods applied for polypectomy of diminutive polyps and clarify whether a diminutive polyp should be retrieved or left in place. Cold biopsy polypectomy is indicated for resection of polyps measuring 1-3 mm and removal of 4-5 mm polyps should be ensured by cold snare polypectomy. Over the last decade, hot biopsy polypectomy has been gradually abandoned because of an increased risk of diathermic injury. The resect and discard strategy and the diagnose and disregard strategy should be performed only by expert endoscopists, who should use validated scales and document the polyp features by storing several endoscopic images. Nowadays, complete resection of diminutive polyps, following the most appropriate technique, is recommended in clinical practice. The resect and discard strategy and the diagnose and disregard strategy should be reserved to expert endoscopists.