Efficacy and safety of cold versus hot snare polypectomy for resecting small colorectal polyps: Systematic review and meta-analysis

Comparing underwater and conventional cold snare polypectomy for colorectal adenomas: Prospective randomized controlled trial

Background and study aims

In this study, we aimed to evaluate efficacy and safety of underwater cold snare polypectomy (UCSP) for treating colorectal adenoma.

Patients and methods

This single-center, prospective, randomized controlled trial screened patients with colorectal adenomas measuring 4 to 9 mm in diameter that were identified through colonoscopies at the Department of Gastroenterology in Jianyang People's Hospital between April 2022 and October 2023. Patients were randomly assigned to undergo UCSP or cold snare polypectomy (CSP). Both groups underwent narrow-band imaging to determine international colorectal endoscopic morphology of type 2 noncancerous lesions. Following polyp removal, biopsy specimens were collected from the base and margins to assess the completeness of resection.

Results

The study included 227 polyps from 172 patients; median sizes in the UCSP (n = 122) and CSP groups (n=105) were 5 mm and 6 mm, respectively. The R0 (96.7% vs. 86.7%; P =0.005) and muscularis mucosa resection rates (68.9% vs. 43.8%; P <0.0001) were significantly higher in the UCSP group than in the CSP group. However, operative time for the UCSP group (109.5 s; 86.8-134.3 vs. 110.0 s; 83.5-143.5 P =0.890) was not significantly longer than that for the CSP group. Neither group exhibited delayed bleeding or perforations.

Conclusions

UCSP has a high R0 rate for colorectal adenomas measuring 4 to 9 mm.

Cold Snare Resection in the Colorectum: When to Choose it, When to Avoid it, and How to Do it

Cold snaring is now the preferred resection method for the majority of colorectal polyps encountered during colonoscopy. A key advantage of cold resection over resection utilizing electrocautery is a substantially lower risk of delayed hemorrhage. Cold snare resection is preferred for all lesions ≤10 mm and for nondysplastic sessile serrated lesions of any size but should be avoided when lesions have a significant risk of submucosal invasion or fibrosis. Cold snare resection can be considered for certain lesions 11-19 mm in size and some lateral spreading lesions ≥20 mm. This review discusses tips and techniques to optimize cold snare resection.

Adverse Events Associated With Endoscopic Retrograde Cholangiopancreatography: Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Endoscopic retrograde cholangiopancreatography (ERCP)-related adverse events (AEs) are associated with morbidity, mortality, and health care expenditure. We aimed to assess incidences and comparisons of ERCP AEs.

METHODS

We included studies performed after 2000 reporting on ERCP AEs from database inception through March 12, 2024. Outcomes included pancreatitis, bleeding, cholangitis, cholecystitis, perforation, and death. DerSimonian and Laird random effects meta-analyses were performed to calculate incidences of AEs. Subgroup and pairwise meta-analyses were performed. Meta-regression was performed on median recruitment year to assess temporal trends in pancreatitis incidence.

RESULTS

A total of 380 studies were included. The incidence of death attributable to ERCP was 0.2% (95% confidence interval [CI], 0.1%-0.3%; I2, 44%; n = 47,258) in all-comers. The overall incidence of pancreatitis was 4.6% (95% CI, 4.0%-5.1%; I2, 96%; n = 293,378) among all-comers and 6.5% (95% CI, 5.9%-7.1%, I2, 89%; n = 88,809) among first-time patients. Pancreatitis incidence remained stable between 2000 and 2023 (average annual percent change 0.06, 95% CI, -0.27 to 0.39). The overall incidences of the following AEs for all-comers were: bleeding (1.5%; 95% CI, 1.2%-1.7%; I2, 93%; n = 229,655), cholangitis (2.5%; 95% CI, 1.9%-3.3%; I2, 96%; n = 121,619), cholecystitis (0.8%; 95% CI, 0.5%-1.2%; I2, 39%; n = 7799), and perforation (0.5%; 95% CI, 0.4%-0.6%; I2, 90%; n = 306,378).

CONCLUSIONS

ERCP-associated AEs remain common. Incidence of post-ERCP pancreatitis remained static despite improvements in techniques, prevention, and recognition. These results are important to patients, endoscopists, and policy makers to inform consent and to encourage implementation of available risk mitigation strategies.

Risk factors for unclear margin in cold snare polypectomy for colorectal polyp

OBJECTIVES

Cold snare polypectomy (CSP) is a common, simple, and safe procedure; however, it has a high rate of unclear margins. We analyzed the risk factors for unclear margins of colorectal polyp.

METHODS

We retrospectively investigated colorectal polyps treated with CSP between July 2021 and July 2022, excluding those that could not be retrieved or pathologically nonneoplastic and hyperplastic polyps without margin evaluation. The clinicopathological features and risk factors for unclear margins were analyzed. Furthermore, the polyps were divided into two groups: those resected by experts and those resected by trainees. A 1 : 1 propensity score matching was performed. After matching, the risk factors for unclear margins in each group were analyzed as secondary outcomes.

RESULTS

We analyzed 237 patients with 572 polyps; the margins were negative in 58.6% (negative group) and unclear in 41.4% (unclear group). The unclear margin was significantly higher at straddling folds ( P  = 0.0001), flexure points ( P  = 0.005), and in the procedures performed by trainees ( P  < 0.0001). Altogether, 198 propensity score matched pairs were explored for secondary outcomes. There were no significant differences in risk factors for unclear margins in the expert group, while in the trainee group, the unclear margin was significantly higher at the straddling folds ( P  = 0.0004) and flexure points ( P  = 0.005).

CONCLUSIONS

We demonstrated that straddling folds, flexure points, and procedures performed by the trainees were significant risk factors for unclear margins, and we hypothesized that the rate of unclear margins will reduce as the trainees accumulate experience at difficult sites.

Histopathologic vertical margin positivity in cold snare polypectomy and mucosal resection for sessile serrated lesions

BACKGROUND AND AIMS

Data regarding the status of the vertical margin of sessile serrated lesions (SSLs) resected using cold snare polypectomy (CSP) are lacking, and whether a histopathologically positive vertical margin is related to recurrence remains unclear. Therefore, this preliminary study aimed to clarify the rates of positive or unassessable vertical and horizontal margins and the rate of muscularis mucosae resection in SSLs treated using CSP compared with those treated with EMR.

METHODS

Histologic outcomes of patients treated with CSP or EMR for SSLs were evaluated in this single-center observational study. The primary outcome was the incidence of histopathologically positive vertical margins in CSP and EMR. Furthermore, the comparisons were adjusted for confounding factors using propensity score matching.

RESULTS

Overall, 82 patients with SSLs were included in the CSP and EMR groups after matching. The incidence of positive histologic vertical margins in the CSP and EMR groups were 67.1% and 2.4%, respectively (P < .001). Regarding the evaluation of the presence of muscularis mucosae, 29.3% and 98.8% of patients in the CSP and EMR groups, respectively, had a complete muscularis mucosae resection (P < .001).

CONCLUSIONS

A rigorous histopathologic evaluation revealed that for SSLs, CSP more frequently leads to positive vertical margins than EMR. (Clinical trial registration number: UMIN 000051569.).

Endoscopic techniques for management of large colorectal polyps, strictures and leaks

The implementation of screening colonoscopy with polyp removal has significantly decreased mortality rates associated with colorectal cancer (CRC), although it remains a major cause of cancer-related deaths globally. CRC typically originates from adenomatous polyps, and increased removal of these growths has led to reduced CRC incidence and mortality. Endoscopic polypectomy techniques, including hot and cold snare polypectomy, play a pivotal role in this process. While both methods are effective for small polyps (<10 mm), recent evidence favors cold snare polypectomy due to its superior safety profile and comparable complete resection rates. Large polyps (>10 mm), particularly those with advanced features, pose increased cancer risks and often require meticulous assessment and advanced endoscopic techniques, including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), for resection. This chapter also provides a practical overview of endoscopic techniques for managing colonic obstructions and pericolonic fluid collections, detailing their indications, advantages, disadvantages, and complications. The goal is to improve understanding and application in clinical practice. Additionally, we provide a summary of endoscopic closure techniques that have revolutionized the management of perforations and fistulas, offering safe and effective alternatives to surgery.

Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024

1:  ESGE recommends cold snare polypectomy (CSP), to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of diminutive polyps (≤ 5 mm).Strong recommendation, high quality of evidence. 2:  ESGE recommends against the use of cold biopsy forceps excision because of its high rate of incomplete resection.Strong recommendation, moderate quality of evidence. 3:  ESGE recommends CSP, to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of small polyps (6-9 mm).Strong recommendation, high quality of evidence. 4:  ESGE recommends hot snare polypectomy for the removal of nonpedunculated adenomatous polyps of 10-19 mm in size.Strong recommendation, high quality of evidence. 5:  ESGE recommends conventional (diathermy-based) endoscopic mucosal resection (EMR) for large (≥ 20 mm) nonpedunculated adenomatous polyps (LNPCPs).Strong recommendation, high quality of evidence. 6:  ESGE suggests that underwater EMR can be considered an alternative to conventional hot EMR for the treatment of adenomatous LNPCPs.Weak recommendation, moderate quality of evidence. 7:  Endoscopic submucosal dissection (ESD) may also be suggested as an alternative for removal of LNPCPs of ≥ 20 mm in selected cases and in high-volume centers.Weak recommendation, low quality evidence. 8:  ESGE recommends that, after piecemeal EMR of LNPCPs by hot snare, the resection margins should be treated by thermal ablation using snare-tip soft coagulation to prevent adenoma recurrence.Strong recommendation, high quality of evidence. 9:  ESGE recommends (piecemeal) cold snare polypectomy or cold EMR for SSLs of all sizes without suspected dysplasia.Strong recommendation, moderate quality of evidence. 10:  ESGE recommends prophylactic endoscopic clip closure of the mucosal defect after EMR of LNPCPs in the right colon to reduce to reduce the risk of delayed bleeding.Strong recommendation, high quality of evidence. 11:  ESGE recommends that en bloc resection techniques, such as en bloc EMR, ESD, endoscopic intermuscular dissection, endoscopic full-thickness resection, or surgery should be the techniques of choice in cases with suspected superficial invasive carcinoma, which otherwise cannot be removed en bloc by standard polypectomy or EMR.Strong recommendation, moderate quality of evidence.

The Safety of Cold Versus Hot Snare Polypectomy in Polyps 10-20 mm: A Systematic Review and Meta-Analysis

Colonoscopy remains the primary method for preventing colorectal cancer. Traditionally, hot snare polypectomy (HSP) was the method of choice for removing polyps larger than 5 mm. Yet, for polyps smaller than 10 mm, cold snare polypectomy (CSP) has become the favored approach. Lately, the use of CSP has expanded to include the removal of sessile polyps that are between 10 and 20 mm in size. Our systematic review and meta-analysis aimed to evaluate the safety of cold snare polypectomy (CSP) compared to hot snare polypectomy (HSP) for resecting polyps measuring 10-20 mm. We searched the Medical Literature Analysis and Retrieval System Online (MEDLINE), Embase, and Cochrane databases up to April 2020 to find studies that directly compared CSP to HSP for polyps larger than 10 mm. Our main focus was on assessing the risk of delayed bleeding after polypectomy; a secondary focus was the incidence of any adverse events that required medical intervention post procedure. Our search yielded three comparative studies, two observational studies, and one randomized controlled trial (RCT), together encompassing 1,193 polypectomy procedures. Of these, 485 were performed using CSP and 708 with HSP. The pooled odds ratio (OR) for post-polypectomy bleeding (PPB) was 0.36 (95% confidence interval {CI}: 0.02, 7.13), with a Cochran Q test P-value of 0.11 and an I2 of 53%. For the risk of any adverse events necessitating medical care, the pooled OR was 0.15 (95% CI: 0.01, 2.29), with a Cochran Q test P-value of 0.21 and an I2 of 35%. The quality of the two observational studies was deemed moderate, and the RCT was only available in abstract form, preventing quality assessment. Our analysis suggests that there is no significant difference in the incidence of delayed post-polypectomy bleeding or other adverse events requiring medical attention between CSP and HSP for polyps measuring 10-20 mm.

Updates on the Prevention and Management of Post-Polypectomy Bleeding in the Colon

Post-polypectomy bleeding (PPB) remains a significant procedure-related complication, with multiple risk factors determining the risk including patient demographics, polyp characteristics, endoscopist expertise, and techniques of polypectomy. Immediate PPB is usually treated promptly, but management of delayed PPB can be challenging. Cold snare polypectomy is the optimal technique for small sessile polyps with hot snare polypectomy for pedunculated and large sessile polyps. Topical hemostatic powders and gels are being investigated for the prevention and management of PPB. Further studies are needed to compare these topical agents with conventional therapy.

AGA Clinical Practice Update on Appropriate and Tailored Polypectomy: Expert Review

DESCRIPTION

In this Clinical Practice Update (CPU), we provide guidance on the appropriate use of different polypectomy techniques. We focus on polyps <2 cm in size that are most commonly encountered by the practicing endoscopist, including use of classification systems to characterize polyps and various polypectomy methods. We review characteristics of polyps that require complex polypectomy techniques and provide guidance on which types of polyps require more advanced management by a therapeutic endoscopist or surgeon. This CPU does not provide a detailed review of complex polypectomy techniques, such as endoscopic submucosal dissection, which should only be performed by endoscopists with advanced training.

METHODS

This expert review was commissioned and approved by the American Gastroenterological Association (AGA) Institute CPU Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the CPU Committee and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. These Best Practice Advice statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these Best Practice Advice statements do not carry formal ratings regarding the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: A structured visual assessment using high-definition white light and/or electronic chromoendoscopy and with photodocumentation should be conducted for all polyps found during routine colonoscopy. Closely inspect colorectal polyps for features of submucosally invasive cancer. BEST PRACTICE ADVICE 2: Use cold snare polypectomy for polyps <10 mm in size. Cold forceps polypectomy can alternatively be used for 1- to 3-mm polyps where cold snare polypectomy is technically difficult. BEST PRACTICE ADVICE 3: Do not use hot forceps polypectomy. BEST PRACTICE ADVICE 4: Clinicians should be familiar with various techniques, such as cold and hot snare polypectomy and endoscopic mucosal resection, to ensure effective, safe, and optimal resection of intermediate-size polyps (10-19 mm). BEST PRACTICE ADVICE 5: Consider using lifting agents or underwater endoscopic mucosal resection for removal of sessile polyps 10-19 mm in size. BEST PRACTICE ADVICE 6: Serrated polyps should be resected using cold resection techniques. Submucosal injection may be helpful for polyps >10 mm if margins cannot be well delineated. BEST PRACTICE ADVICE 7: Use hot snare polypectomy to remove pedunculated lesions >10 mm in size. BEST PRACTICE ADVICE 8: Do not routinely use clips to close resection sites for polyps <20 mm. BEST PRACTICE ADVICE 9: Refer patients with polyps to endoscopic referral centers in the context of size ≥20 mm, challenging polypectomy location, or recurrent polyp at a prior polypectomy site. BEST PRACTICE ADVICE 10: Tattoo lesions that may need future localization at endoscopy or surgery. Tattoos should be placed in a location that will not interfere with subsequent attempts at endoscopic resection. BEST PRACTICE ADVICE 11: Refer patients with nonpedunculated polyps with clear evidence of submucosally invasive cancer for surgical evaluation. BEST PRACTICE ADVICE 12: Understand the endoscopy suite's electrosurgical generator settings appropriate for polypectomy or postpolypectomy thermal techniques.

Ischemic Polypectomy Through Detachable Snare and Rubber Band Ligation in Peutz-Jeghers Syndrome

Endoscopic polypectomy is essential for the prevention of Peutz-Jeghers syndrome-associated complications, including intussusception, intestinal obstruction, and malignant transformation. Conventional polypectomy is the preferred approach, but it can be challenging to achieve in patients with Peutz-Jeghers syndrome because of the high polyp burden and polyps located in areas with difficult endoscopic access. This case report highlights 2 different techniques of ischemic polypectomy and its advantage compared with conventional polypectomy in this subset of patients.

Efficacy and Safety of Cold Snare Polypectomy versus Cold Endoscopic Mucosal Resection for Resecting 3-10 mm Colorectal Polyps: Systematic Review and Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

The safety and efficacy of cold snare polypectomy (CSP) compared to those of cold endoscopic mucosal resection (CEMR) have been reported. This meta-analysis compared the efficacy and safety of CEMR and CSP.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library databases were systematically searched to identify randomized controlled trials comparing the efficacy and safety of CEMR and CSP in removing 3-10 mm polyps. The outcomes assessed included complete resection rate, intraoperative bleeding rate, delayed bleeding rate, perforation, and polyp removal time. The results are reported as risk ratios (RR) and 95% confidence intervals (CIs) derived from a Mantel-Haenszel random-effects model.

RESULTS

Seven studies comprising 1,911 polyps were included in the analysis. The complete resection rate of CEMR was comparable to that of CSP (RR: 1.01, 95% CI: 0.99-1.04, p = 0.32). Comparable results were also demonstrated for intraoperative bleeding rate (polyp-based analysis: RR: 1.22, 95% CI: 0.33-4.43, p = 0.77), delayed bleeding rate (polyp-based analysis: RR: 1.34, 95% CI: 0.44-4.15, p = 0.61), and polyp removal time (mean difference: 28.31 s, 95% CI: -21.40-78.02, p = 0.26). No studies reported cases of perforation.

CONCLUSION

CEMR has comparable efficacy and safety to CSP in removing 3-10 mm polyps. Further randomized controlled trials with long-term follow-up are warranted to compare and validate efficacy.

Phlegmonous Colitis after Cold Snare Polypectomy in an Immunosuppressed Patient: A Case Report

Introduction

Cold snare polypectomy (CSP) is a procedure with a low risk of complications. Here, we present our experience of a rare case of submucosal abscess following CSP in an immunosuppressed patient.

Case Presentation

Seventy-eight-year-old man underwent CSP, developing a fever, chills, and right lower abdominal pain 8 days later. Ultrasound and computed tomography revealed wall thickening of the ascending colon, presenting as whitening and thickening of the same region, and excretion of pus was observed after biopsy. The diagnosis was made as phlegmonous colitis, for which antibiotic therapy was commenced. The patient was diagnosed with chronic myelomonocytic leukemia (CMML) during admission. We considered the following reasons as possible causes of infectious complications after CSP: (1) the patient had a highly immunosuppressed state with comorbidities such as CMML as well as diabetes mellitus and (2) disruption of the mucosal barrier occurred during endoscopic resection.

Conclusion

Although CSP is generally considered safe, our case highlights the potential for serious complications in immunosuppressed patients. Therefore, the decision to perform CSP in such patients should be made with caution to avoid unnecessary interventions. In instances where treatment is essential, thorough bowel preparation and prophylactic antibiotic use may be necessary to mitigate the risks.

Endoscopic treatment of colorectal polyps and early colorectal cancer

Background: Colonoscopy offers higher diagnostic sensitivity than other colorectal cancer screening methods and provides the advantage of both diagnostic tissue sampling and polyp removal. Since the majority of colorectal cancers evolve from adenomatous polyps, polyp resection through colonoscopy is widely considered an effective method of preventing colorectal cancer and reducing mortality rates.Current Concepts: Determining colorectal polyp size and shape requires comprehensive endoscopy with enhanced imaging techniques to choose treatment directions and the appropriate colorectal polypectomy method. The selection of the polypectomy method is contingent upon the polyp’s attributes and possible malignancy according to US Multi-Society Task Force on Colorectal Cancer and European gastrointestinal endoscopy guidelines. This article examines eight polypectomy procedures: cold forceps polypectomy, hot biopsy polypectomy, cold snare polypectomy, hot snare polypectomy, endoscopic mucosal resection (EMR), and modified EMR techniques. Each method has unique benefits and is suitable for particular polyp types and sizes. Piecemeal EMR and endoscopic submucosal dissection offer alternatives for larger or challenging lesions that require careful planning and follow-up. After endoscopic resection of early colorectal cancer, further surgery may be necessary depending on the risk of lymph node metastasis as determined by specific histologic findings following Korean and Japanese guidelines.Discussion and Conclusion: The choice of endoscopic resection technique, which depends on factors such as polyp shape, size, and location as well as endoscopist skill, is crucial for ensuring complete polyp removal.

The efficacy and safety of cold snare polypectomy with submucosal injection for the removal of polyps less than 20 mm in size: a systematic review and meta-analysis

BACKGROUND AND AIM

Neoplastic polyp removal is important for colorectal cancer prevention. Endoscopists have proposed cold snare endoscopic mucosal resection (CS-EMR) as a solution to solve positive cutting edges and postoperative bleeding. However, many controversies regarding its specific performance in practice have been reported. The aim of this pooled analysis was to report the efficacy and safety of CS-EMR.

METHODS

PubMed/Medline, Embase, Google Scholar, and the Cochrane Library searched up to January 2022 to identify studies in which CS-EMR was performed for the removal of colorectal polyps measuring less than 20 mm. The primary outcome was the complete resection rate (CRR), and the secondary outcome was the rate of adverse events.

RESULTS

Eleven studies were included in the final analysis, which included 861 colorectal polyps. The overall CRR with CS-EMR was 96.3% (95% CI, 93.9-98.2%). The early and delayed bleeding rates of CS-EMR were 3.1% (95% CI, 1.2-5.5%) and 1.4% (95% CI, 0.6-2.4%), respectively. There were no statistical significances between CS-EMR and cold snare polypectomy (CSP) in terms of the CRR and adverse events, as well as CS-EMR and hot snare endoscopic mucosal resection (HS-EMR).

CONCLUSIONS

For resecting colorectal polyps measuring ≤20 mm, CS-EMR is an effective attempt. However, compared with CSP and HS-EMR, CS-EMR did not improve the efficiency and safety of polypectomy as expected. Multicenter randomized controlled trials are needed to compare CSP with CS-EMR in the resection of <10 mm polyps and HSP with CS-EMR in the resection of ≥10 mm polyps.

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

BACKGROUND

Polypectomy is an important treatment option for preventing colorectal cancer. Incomplete polyp resection (IPR) is re-cognized as a risk factor for interval cancer.

OBJECTIVE

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.

METHODS

We prospectively evaluated 479 polyps <10 mm removed by CSP in 276 patients by an inexperienced endoscopist.

RESULTS

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.

CONCLUSION

CSP is a safe technique that provides good results for the resection of small non-pedunculated polyps, with a short learning curve.

Systematic review and meta-analysis of cold snare polypectomy and hot snare polypectomy for colorectal polyps

BACKGROUND AND AIM

Cold snare polypectomy (CSP) has become increasingly utilized to resect colorectal polyps, given its efficacy and safety. This study aims to compare CSP and hot snare polypectomy (HSP) for resecting small (< 10 mm) and large (10-20 mm) colorectal lesions.

METHODS

Relevant publications were obtained from Cochrane Library, Embase, Google Scholar, PubMed, and Web of Science databases. The publication search was limited by English-language and human studies. Pooled mean difference and odds ratios (ORs) were calculated for outcomes of interest.

RESULTS

Twenty-three studies were included in this meta-analysis. Pooled OR of delayed post-polypectomy bleeding (DPPB) in the CSP group versus the HSP group was 0.29 (P = 0.0001, I2  = 29%). Subgroup analysis according to lesion size showed a significant reduction in the DPPB rate in lesion sizes 10-20 mm (pooled OR 0.08, P = 0.003, I2  = 0%) and < 10 mm (pooled OR 0.35, P = 0.001, I2  = 27%). Pooled OR of major bleeding in the CSP group was 0.23 (P = 0.0004, I2  = 0%). Subgroup analysis by lesion size revealed a significant decrease in the rate of major bleeding in the CSP group for both lesion sizes 10-20 mm (pooled OR 0.11, P = 0.04) and < 10 mm (pooled OR 0.26, P = 0.003). Complete resection, en bloc resection, and recurrence rate were comparable in the two groups.

CONCLUSIONS

Cold snare polypectomy was associated with a lower rate of DPPB and lower risk of major bleeding compared with HSP in both small and large polyps. CSP should be considered as the polypectomy technique of choice for colorectal polyps.

Evaluation of a new method, "non-injection resection using bipolar soft coagulation mode (NIRBS)", for colonic adenomatous lesions

BACKGROUND/AIMS

Endoscopic resection of all colorectal adenomatous lesions with a low complication rate, simplicity, and negative residuals is challenging. Hence, we developed a new method called "non-injection resection using bipolar soft coagulation mode (NIRBS)" method, adapted for colorectal lesions. In addition, we evaluated the effectiveness of this method.

METHODS

We performed NIRBS throughout a 12-month period for all colorectal lesions which snare resection was acceptable without cancerous lesions infiltrating deeper than the submucosal layer.

RESULTS

A total of 746 resected lesions were included in the study, with a 4.5 mm mean size (range, 1-35 mm). The major pathological breakdowns were as follows: 64.3% (480/746) were adenomas, and 5.0% (37/746) were intraepithelial adenocarcinomas (Tis lesions). No residuals were observed in any of the 37 Tis lesions (mean size, 15.3 mm). Adverse events included bleeding (0.4%) but no perforation.

CONCLUSIONS

NIRBS allowed the resection of multiple lesions with simplicity because of the non-injection and without perforating due to the minimal burn effect of the bipolar snare set in the soft coagulation mode. Therefore, NIRBS can be used to resect adenomatous lesions easily, including Tis lesions, from small to large lesions without leaving residuals.

Cold Versus Hot Snare Polypectomy for Colorectal Polyps: An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND AND OBJECTIVE

Endoscopic polypectomy is an excellent tool for colon cancer prevention. With the innovation of novel resection techniques, the best method is still being investigated. Hence, we aim to evaluate the efficacy and safety of cold snare polypectomy (CSP) versus hot snare polypectomy (HSP) for colorectal polyp resection.

METHODS

A systematic review and meta-analysis synthesizing evidence from randomized controlled trials retrieved from PubMed, EMBASE, WOS, SCOPUS, and CENTRAL until July 16, 2022. We pooled dichotomous outcomes using risk ratio (RR) with the corresponding CI. This review's protocol was prospectively registered in PROSPERO with ID: CRD42022347496.

RESULTS

We included 18 randomized controlled trials with a total of 4317 patients and 7509 polyps. Pooled RR favored HSP regarding the complete resection rate (RR: 0.96 with 95% CI: 0.95, 1, P = 0.03) and local recurrence incidence (RR: 5.74 with 95% CI: 1.27, 25.8, P = 0.02). Pooled RR favored CSP regarding the colonoscopy time (mean difference: -6.50 with 95% CI: -7.55, -5.44, P = 0.00001) and polypectomy time (mean difference: -57.36 with 95% CI: -81.74, -32.98, P = 0.00001). There was no difference regarding the incidence of immediate bleeding ( P = 0.06) and perforation ( P = 0.39); however, HSP was associated with more incidence of delayed bleeding ( P = 0.01), abdominal pain ( P = 0.007), and postresection syndrome ( P = 0.02).

DISCUSSION

HSP is associated with a higher complete resection and lower recurrence rates; however, HSP is also associated with a higher incidence of adverse events. Therefore, improving the complete resection rate with CSP still warrants more innovation, giving the technique safety and shorter procedure duration.

Comparative efficacy and safety of resection techniques for treating 6 to 20mm, nonpedunculated colorectal polyps: A systematic review and network meta-analysis

INTRODUCTION

Various endoscopic resection techniques have been proposed for the treatment of nonpedunculated colorectal polyps sized 6-20 mm, however the optimal technique still remains unclear.

METHODS

A comprehensive literature review was conducted for randomized controlled trials (RCTs), investigating the efficacy of endoscopic treatments for the management of 6-20 mm nonpedunculated colorectal polyps. Primary outcomes were complete and en bloc resection rates and adverse event rate was the secondary. Effect size on outcomes is presented as risk ratio (RR; 95% confidence interval [CI]).

RESULTS

Fourteen RCTs (5219 polypectomies) were included. Endoscopic mucosal resection(EMR) significantly outperformed cold snare polypectomy(CSP) in terms of complete [(RR 95%CI): 1.04(1.00-1.07)] and en bloc resection rate [RR:1.12(1.04-1.21)]. EMR was superior to hot snare polypectomy (HSP) [RR:1.04(1.00-1.08)] regarding complete resection, while underwater EMR (U-EMR) achieved significantly higher rate of en bloc resection compared to CSP [RR:1.15(1.01-1.30)]. EMR yielded the highest ranking for complete resection(SUCRA-score 0.81), followed by cold-snare EMR(CS-EMR,SUCRA-score 0.76). None of the modalities was different regarding adverse event rate compared to CSP, however EMR and CS-EMR resulted in fewer adverse events compared to HSP [RR:0.44(0.26-0.77) and 0.43(0.21-0.87),respectively].

CONCLUSION

EMR achieved the highest performance in resecting 6-20 mm nonpedunculated colorectal polyps, with this effect being consistent for polyps 6-9 and ≥10 mm; findings supported by very low quality of evidence.

Cold resection for colorectal polyps: where we are and where we are going?

INTRODUCTION

Endoscopic resection of colonic precancerous lesions has been demonstrated to significantly decrease colorectal cancer (CRC) incidence and mortality. Among resection techniques, cold snare polypectomy (CSP) has been shown as a highly feasible, effective and safe option and is widely used in clinical practice, being regarded as the first-line technique for removal of small and diminutive colorectal polyps. On the other hand, conventional hot snare polypectomy (HSP) and endoscopic mucosal resection (EMR), namely the gold standard treatments for larger polyps, may be occasionally associated to complications due to electrocautery injury.

AREAS COVERED

To overcome these shortcomings of electrocautery-based resection techniques, in the last few years CSP has been increasingly assessed as a treatment option for additional indications, with a focus on nonpedunculated colorectal polyps ≥10 mm.

EXPERT OPINION

This review aims to present current and widened indications of CSP discussing the latest findings from the most remarkable studies, with an insight into technical issues, novelties and potential advances in the near future.

Bleeding After Endoscopic Resection of Colonic Adenomatous Polyps Sized 4-10 mm

Introduction: Colonoscopy with polypectomy is an efficacious procedure in reducing the risk of colorectal cancer development, the precursor are adenomatous polyps. The most common method for resection of polyps measuring 4-10 mm are cold (CSP) and hot snare polypectomy (HSP). CSP has a lower incidence of adverse events, especially delayed post-polypectomy bleeding. Aim: To evaluate the presence of immediate and delayed bleeding in the cold snare polypectomy of sub-centimeter polyps of the colon compared with hot snare polypectomy. Materials and Methods: This prospective clinical study is comprised all patients who were incidentally detected to have adenomatous colonic polyps measuring 4-10 mm during a colonoscopy screening. Polypectomy was done with (hot snare) or without electrocautery (cold snare). After removal of polyps, immediate bleeding, delayed bleeding, and methods for were analyzed. Results: The CSP and HSP groups included 116 patients, 113 (54.4%) polyps in 61 (52.6%) patients with CSP while 95 (45.6%) polyps in 55 (47.4%) patients with HSP. 25 (22.1%) polyps after CSP had immediate bleeding. In 5 patients (20.0%), five hemostatic clips were inserted after CSP for bleeding longer than 150 sek. The average percentage difference between immediate bleeding versus total number of resected polyps using the cold snare method is not statistically significant (p<0.05) (Difference test, p=0.0000). Delayed bleeding was not registered using this method. In the second investigated group (HSP), one patient had delayed bleeding. This was stopped with 2 clips. Immediate bleeding was not registered. Conclusion: CSP is safer than HSP in resecting colon polyps sized 4-10 mm, without risk of delayed bleeding.

The efficacy and safety of cold snare versus hot snare polypectomy for endoscopic removal of small colorectal polyps: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

The optimal technique for removing small colorectal polyps ranging from 5 to 10 mm in size remains uncertain. In order to compare the efficacy and adverse events between cold snare polypectomy (CSP) and hot snare polypectomy (HSP) for removing small polyps, we conducted a systematic review and meta-analysis of available randomized controlled trials.

METHODS

We conducted a comprehensive search of MEDLINE, EMBASE, and the Cochrane Library databases from 1998 to May 2023 to identify randomized controlled trials that evaluated the efficacy and safety of cold snare polypectomy (CSP) and hot snare polypectomy (HSP) for resecting small colorectal polyps. The primary outcome measure was the incomplete resection rate (IRR).

RESULTS

Seven studies that met our study criteria, with a total of 3178 included polyps, were included in our analysis. The incomplete resection rate (IRR) was found to be significantly higher in the CSP group compared to the HSP group (risk ratio [RR] 1.57 [1.17-2.11], P = 0.003). Although the CSP group had a higher local recurrence rate than the HSP group, the difference was not statistically significant (RR: 3.98 [0.66-23.84], P = 0.13). The polyp retrieval rates were not significantly different between the two groups (RR: 1.00 [0.99-1], P = 0.22). Perforation was not reported or mentioned in any of the seven studies. The overall immediate bleeding rate was significantly higher in the CSP group than the HSP group (RR: 2.26 [1.63-3.14], P < 0.001), but immediate postpolypectomy bleeding requiring additional intervention was similar between the groups (RR: 1.08 [0.54-2.17], P = 0.82). The delayed bleeding rate (RR: 0.83 [0.45-1.55], P = 0.56) and specific polypectomy time (RR: -0.46 [-1.05-0.12], P = 0.12) were also similar between the groups.

CONCLUSIONS

The meta-analysis shows a significantly higher IRR for CSP compared with HSP when removing small polyps.

Submucosal Injection Using Epinephrine-Added Saline in Cold Snare Polypectomy for Colorectal Polyps Shortens Time Required for Resection: A Randomized Controlled Study

AIMS

Immediate bleeding after cold snare polypectomy (CSP) for colorectal polyps might interfere with confirmation of residuals and prolong the time required for resection. We investigated whether submucosal epinephrine-added saline injection reduces the time required for the CSP procedure.

METHODS

We conducted a single-center, prospective, randomized controlled trial (clinical trial registration number: UMIN000046770). Patients with colorectal polyps ≤ 10 mm were randomly allocated to either CSP with epinephrine-added submucosal injection (CEMR group) or conventional CSP (CSP group). The primary outcome was the time required for resection defined as the time from the initiation of resection (the first insertion of the snare in the CSP group or the injection needle in the CEMR group) to the end of resection (confirming complete resection endoscopically after recognizing the cessation of immediate bleeding) in each lesion, and the secondary outcome was the time to spontaneous cessation of immediate bleeding after resection defined as the time from ensnaring the lesion to confirming the spontaneous cessation of immediate bleeding.

RESULTS

A total of 126 patients were randomly assigned. Finally, 261 lesions in 118 patients (CEMR group, n = 59; CSP group, n = 59) were analyzed. The time required for resection calculated using the least-square mean was significantly shorter in the CEMR group (106.3 s, 95% CI 97.5 to 115.4 s) than in the CSP group (130.9 s, 95% CI 121.2 to 140.7 s) (P < 0.001). The time to spontaneous cessation of immediate bleeding was also significantly shorter in the CEMR group (20.4 s, 95% CI 14.3 to 26.5 s) than in the CSP group (74.2 s, 95% CI 67.6 to 80.7 s) (P < 0.001). Neither group had cases requiring hemostasis, perforation, or delayed bleeding.

CONCLUSIONS

CEMR shortened the time for resection by shortening the time to cessation of immediate bleeding compared with conventional CSP in colorectal polyps ≤ 10 mm.

Endoscopic resection of non-ampullary duodenal adenomas: Is cold snaring the promised land?

Due to the high risk of morbidity and mortality associated with surgical resection in this tract, endoscopic resection (ER) has taken the place of surgical resection as the first line treatment for non-ampullary duodenal adenomas. However, due to the anatomical characteristics of this area, which enhance the risk of post-ER problems, ER in the duodenum is particularly difficult. Due to a lack of data, no ER technique for superficial non-ampullary duodenal epithelial tumours (SNADETs) has yet been backed by strong, high-quality evidence; yet, traditional hot snare-based techniques are still regarded as the standard treatment. Despite having a favourable efficiency profile, adverse events during duodenal hot snare polypectomy (HSP) and hot endoscopic mucosal resection, such as delayed bleeding and perforation, have been reported to be frequent. These events are primarily caused by electrocautery-induced damage. Thus, ER techniques with a better safety profile are needed to overcome these shortcomings. Cold snare polypectomy, which has already been shown as a safer, equally effective procedure compared to HSP for treatment of small colorectal polyps, is being increasingly evaluated as a potential therapeutic option for non-ampullary duodenal adenomas. The aim of this review is to report and discuss the early outcomes of the first experiences with cold snaring for SNADETs.

Colorectal cold snare polypectomy: Current standard technique and future perspectives

It has been shown that resection of adenomatous colorectal polyps can reduce mortality due to colorectal cancer. In daily clinical practice, simpler and safer methods of colorectal polypectomy have been sought to enable endoscopists to resect all detected lesions. Among these, cold snare polypectomy (CSP) is widely used in clinical practice because of its advantages in shortening procedure time, reducing delayed bleeding risk, and lowering treatment costs, while maintaining a similar complete resection rate for lesions smaller than 10 mm when compared to conventional hot snare polypectomy. This review introduces the findings of previous studies that investigated the efficacy and safety of the CSP procedure for nonpedunculated polyps smaller than 10 mm, and describes technical points to remember when practicing CSP based on the latest evidence, including using a thin wire snare specifically designed for CSP, and observing the surrounding mucosa of the resection site with chromoendoscopy or image-enhanced endoscopy to ensure that there is no residual lesion. This review also describes the potential of expanding the indication of CSP as a treatment for lesions larger than 10 mm, those with pedunculated morphology, those located near the appendiceal orifice, and for patients under continuous antithrombotic agent therapy. Finally, the perspective on optimal treatments for recurrent lesions after CSP is also discussed, despite the limited related evidence and data.

Bleeding Risk With Cold Snare Polypectomy of ≤10 mm Pedunculated Colon Polyps

OBJECTIVES

Pedunculated polyps (PPs) in the colon are usually resected with hot snare polypectomy to prevent immediate postpolypectomy bleeding (IPPB). This study aimed to evaluate the safety of CSP of <10 mm PPs.

MATERIALS AND METHODS

Patients undergoing colonoscopy from February 18, 2019, to April 24, 2020, and were found to have at least 1 ≤10 mm PP resected with CSP were included prospectively in a continuous quality improvement project to assess the risk of IPPB and delayed postpolypectomy bleeding. Polyp location, size, and pathology, as well as the method of resection, were recorded. In addition, we assessed the occurrence and severity of IPPB and the need for intervention.

RESULTS

We found 239 eligible polyps in 182 patients. The mean (SD) age was 58.8 (8.3) years, and 61% were males. IPPB occurred in 72 of 239 polyps, corresponding to a per-polyp bleeding percentage of 30.1% and in 65 of 182 patients, equating to a per-patient bleeding rate of 35.7%. We successfully treated bleeding by endoscopic hemostasis in 57%; the remaining 31 polyps (43%) did not require endoscopic intervention. There was no association between IPPB with age, gender, or use of aspirin or antithrombotic agents. In the bivariate model, polyp size and pathology were not associated with the risk of IPPB. Right-sided polyps were associated with a reduced risk of IPPB in the bivariate model by 61% (odds ratio=0.39; 95% confidence interval, 0.21-0.74; P =0.0057). In the multivariate model, choking the polyp base decreased the likelihood of IPPB by 97% (odds ratio=0.03; 95% confidence interval, 0.00-0.86; P =0.0459). There were no instances of delayed bleeding, perforation, or postpolypectomy syndrome.

CONCLUSIONS

CSP can be used for resection of ≤10 mm PPs. It is associated with a lower risk of immediate bleeding than the common perception among gastroenterologists.

Cold Versus Hot Snare Polypectomy for Small Colorectal Polyps : A Pragmatic Randomized Controlled Trial

BACKGROUND

Although cold snare polypectomy (CSP) is considered effective in reducing delayed postpolypectomy bleeding risk, direct evidence supporting its safety in the general population remains lacking.

OBJECTIVE

To clarify whether CSP would reduce delayed bleeding risk after polypectomy compared with hot snare polypectomy (HSP) in the general population.

DESIGN

Multicenter randomized controlled study. (ClinicalTrials.gov: NCT03373136).

SETTING

6 sites in Taiwan, July 2018 through July 2020.

PARTICIPANTS

Participants aged 40 years or older with polyps of 4 to 10 mm.

INTERVENTION

CSP or HSP to remove polyps of 4 to 10 mm.

MEASUREMENTS

The primary outcome was the delayed bleeding rate within 14 days after polypectomy. Severe bleeding was defined as a decrease in hemoglobin concentration of 20 g/L or more, requiring transfusion or hemostasis. Secondary outcomes included mean polypectomy time, successful tissue retrieval, en bloc resection, complete histologic resection, and emergency service visits.

RESULTS

A total of 4270 participants were randomly assigned (2137 to CSP and 2133 to HSP). Eight patients (0.4%) in the CSP group and 31 (1.5%) in the HSP group had delayed bleeding (risk difference, -1.1% [95% CI, -1.7% to -0.5%]). Severe delayed bleeding was also lower in the CSP group (1 [0.05%] vs. 8 [0.4%] events; risk difference, -0.3% [CI, -0.6% to -0.05%]). Mean polypectomy time (119.0 vs. 162.9 seconds; difference in mean, -44.0 seconds [CI, -53.1 to -34.9 seconds]) was shorter in the CSP group, although successful tissue retrieval, en bloc resection, and complete histologic resection did not differ. The CSP group had fewer emergency service visits than the HSP group (4 [0.2%] vs. 13 [0.6%] visits; risk difference, -0.4% [CI, -0.8% to -0.04%]).

LIMITATION

An open-label, single-blind trial.

CONCLUSION

Compared with HSP, CSP for small colorectal polyps significantly reduces the risk for delayed postpolypectomy bleeding, including severe events.

PRIMARY FUNDING SOURCE

Boston Scientific Corporation.

Endoscopic features and clinical course of colorectal carcinoma resected by cold snare polypectomy

BACKGROUND AND AIM

Cold snare polypectomy is commonly performed to remove small colorectal polyps. Accidental resection of carcinomas during this procedure has been reported. Herein, we aimed to clarify the clinicopathological features and clinical course of colorectal carcinomas resected by cold snare polypectomy.

METHODS

This multicenter retrospective cohort study was conducted at 10 Japanese healthcare centers. Of the colorectal lesions resected by cold snare polypectomy between April 2016 and March 2020, lesions pathologically diagnosed as carcinoma were reviewed. Centralized histology (based on the Vienna classification) and endoscopic reviews were performed. The study endpoints were endoscopic features and clinical outcomes of cold snare polypectomy-resected colorectal carcinomas (Vienna category ≥4.2).

RESULTS

We reviewed 74 of the 70 693 lesions resected by cold snare polypectomy. After a central pathological review, 68 lesions were diagnosed as carcinomas. The Japan Narrow-band imaging Expert Team (JNET) classification type 2B, lesion size ≥6 mm, and multinodular morphology were the significant endoscopic predictors of carcinoma resected by cold snare polypectomy. No adverse events related to the procedure occurred. Sixty-three lesions were diagnosed as carcinomas within the mucosal layer, and 34 were curative resections. Of the five carcinoma lesions with submucosal invasion, additional surgery revealed remnant cancer tissues in one lesion. No local or metastatic recurrence was observed during follow-up.

CONCLUSIONS

Although most of the carcinomas resected by cold snare polypectomy were within the mucosal layer, few lesions invading the submucosa were identified. Careful pre-procedural endoscopic evaluation, especially focusing on the JNET classification and multinodular morphology, is recommended.

JAG consensus statements for training and certification in flexible sigmoidoscopy

INTRODUCTION

Joint Advisory Group (JAG) certification in endoscopy is awarded when trainees attain minimum competency standards for independent practice. A national evidence-based review was undertaken to update standards for training and certification in flexible sigmoidoscopy (FS).

METHODS

A modified Delphi process was conducted between 2019 and 2020 with multisociety representation from experts and trainees. Following literature review and Grading of Recommendations, Assessment, Development and Evaluations appraisal, recommendation statements on FS training and certification were formulated and subjected to anonymous voting to obtain consensus. Accepted statements were peer-reviewed by national stakeholders for incorporation into the JAG FS certification pathway.

RESULTS

In total, 41 recommendation statements were generated under the domains of: definition of competence (13), acquisition of competence (17), assessment of competence (7) and postcertification support (4). The consensus process led to revised criteria for colonoscopy certification, comprising: (A) achieving key performance indicators defined within British Society of Gastroenterology standards (ie, rectal retroversion >90%, polyp retrieval rate >90%, patient comfort <10% with moderate-severe discomfort); (B) minimum procedure count ≥175; (C) performing 15+ procedures over the preceding 3 months; (D) attendance of the JAG Basic Skills in Lower gastrointestinal Endoscopy course; (E) satisfying requirements for formative direct observation of procedural skill (DOPS) and direct observation of polypectomy skill (SMSA level 1); (F) evidence of reflective practice as documented on the JAG Endoscopy Training System reflection tool and (G) successful performance in summative DOPS.

CONCLUSION

The UK standards for training and certification in FS have been updated to support training, uphold standards in FS and polypectomy, and provide support to the newly independent practitioner.

JAG consensus statements for training and certification in colonoscopy

INTRODUCTION

In the UK, endoscopy certification is awarded when trainees attain minimum competency standards for independent practice. A national evidence-based review was undertaken to update and develop standards and recommendations for colonoscopy training and certification.

METHODS

Under the oversight of the Joint Advisory Group (JAG), a modified Delphi process was conducted between 2019 and 2020 with multisociety expert representation. Following literature review and Grading of Recommendations, Assessment, Development and Evaluations appraisal, recommendation statements on colonoscopy training and certification were formulated and subjected to anonymous voting to obtain consensus. Accepted statements were peer reviewed by JAG and relevant stakeholders for incorporation into the updated colonoscopy certification pathway.

RESULTS

In total, 45 recommendation statements were generated under the domains of: definition of competence (13), acquisition of competence (20), assessment of competence (8) and postcertification support (4). The consensus process led to revised criteria for colonoscopy certification, comprising: (1) achieving key performance indicators defined within British Society of Gastroenterology standards (ie, unassisted caecal intubation rate >90%, rectal retroversion >90%, polyp detection rate >15%+, polyp retrieval rate >90%, patient comfort <10% with moderate-severe discomfort); (2) minimum procedure count 280+; (3) performing 15+ procedures over the preceding 3 months; (4) attendance of the JAG Basic Skills in Colonoscopy course; (5) terminal ileal intubation rates of 60%+ in inflammatory bowel disease; (6) satisfying requirements for formative direct observation of procedure skills (DOPS) and direct observation of polypectomy skills (Size, Morphology, Site, Access (SMSA) level 2); (7) evidence of reflective practice as documented on the JAG Endoscopy Training System reflection tool; (8) successful performance in summative DOPS.

CONCLUSION

The UK standards for training and certification in colonoscopy have been updated, culminating in a single-stage certification process with emphasis on polypectomy competency (SMSA Level 2+). These standards are intended to support training, improve standards of colonoscopy and polypectomy, and provide support to the newly independent practitioner.

Different endoscopic treatments for small colorectal polyps: A systematic review, pair-wise, and network meta-analysis

Background and study aims

In recent years, cold snare polypectomy (CSP) has been increasingly used for small polyps (<10 mm) instead of hot snare polypectomy (HSP). However, evidence-based research regarding the effectiveness and safety of CSP and HSP are still lacking. Additionally, for 4-10 -mm non-pedunculated polyps, the polyp removal method is still controversial. Therefore, it is clinically significant to conduct pair-wise and network meta-analyses to assess such resection methods.

Methods

We searched PubMed, Embase, and the Cochrane library for randomized controlled trials (RCTs). Only studies that involved the resection of polyps <10 mm were included. Outcomes included the complete resection rate, polyp retrieval rate, procedure-related complications, and procedure times.

Results

Overall, 23 RCTs (5,352 patients) were identified. In meta-analysis compared CSP versus HSP for polyps <10 mm, CSP showed lower complete resection rate than HSP although with no statistically significant difference [odds ratio (OR): 0.77, 95% confidence interval (CI): 0.56-1.06]. CSP showed a lower risk of major post-polypectomy complications compared to HSP (OR: 0.28, 95% CI: 0.11-0.73). In the network meta-analysis for 4-10 mm non-pedunculated polyps, HSP, and endoscopic mucosal resection (EMR) showed a higher complete resection rate than CSP (OR: 2.7, 95% CI: 1.3-9.2 vs. OR: 2.6, 95% CI: 1.0-10) but a significantly longer time than CSP (WMD: 16.55 s, 95% CI [7.48 s, 25.25 s], p < 0.001), (WMD: 48.00 s, 95% CI [16.54 s, 79.46 s], p = 0.003). Underwater CSP ranked third for complete resection with no complications.

Conclusion

For <10 mm polyps, CSP is safer than HSP, especially for patients taking antithrombotic drugs. For 4-10 mm non-pedunculated polyps, HSP, and EMR have higher complete resection rates than CSP.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022315575.

Feasibility and Safety of Endoscopic Ischemic Polypectomy and Clinical Outcomes in Patients with Peutz-Jeghers Syndrome (with Video)

OBJECTIVES

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant hereditary disease with a clinical features related to gastrointestinal (GI) hamartomatous polyposis, frequently observed in the small bowel. Balloon-assisted enteroscopy (BAE) has made non-surgical treatment of GI polyps possible. Endoscopic mucosal resection (EMR) has been performed but was associated with complications and difficulties. Recently, endoscopic ischemic polypectomy (EIP) has been developed and its usefulness reported. The study evaluated the feasibility and safety of EIP and the clinical outcomes of patients with PJS.

METHODS

We retrospectively collected data of consecutive patients with PJS between September 2009 and March 2021. Data regarding clinical characteristics, follow-up methods, endoscopic management, and complications were collected. EIP feasibility and safety were assessed.

RESULTS

Twenty-two patients were included. The observation period was 70 months (range, 5-153). Of the 124 therapeutic endoscopy procedures performed, 68 used BAE. Of the 607 polyps treated, 329 polyps were located in the small bowel. EIP was able to treat a greater number of polyps per patient than EMR (P < 0.003), without any complications, carcinoma, or intussusception in the small bowel (P < 0.001). During the follow-up period, 3 patients developed GI cancer.

CONCLUSION

Long-term follow-up in patients with PJS showed that EIP was a feasible and safe technique.

Large submucosal hematoma after cold snare polypectomy for colorectal adenoma

Cold snare polypectomy (CSP), for the treatment of colorectal polyps, has become widespread due to its low incidence of adverse events compared to that of endoscopic procedures such as endoscopic mucosal resection. However, we experienced a case of large hematoma development shortly after CSP for a colorectal adenoma despite no bleeding during the procedure. The patient underwent CSP for a 7-mm type Isp lesion in the ascending colon. She returned the following day because of hematochezia. Computed tomography showed a 70-mm, high-intensity mass in the ascending colon, consistent with the large hematoma that was detected by colonoscopy. Although the patient initially had right-sided abdominal pain, it gradually improved with conservative treatment. The hematoma decreased in size, and she was discharged 20 days after emergency admission. Although CSP can be a favorable alternative to more invasive procedures and is expected to be performed more frequently, adverse events, such as that described in this case, should be anticipated.

Progression in clinical application of cold snare resection technique in colorectal polyps

The cold snare resection technique has been recommended by European and American societies and gradually applied in clinical practice. However, due to the operating habits of endoscopists and the insufficient understanding of the cold resection technique, it has not been fully used in colorectal polyps. In this paper, we review the application status of cold snare resection technique, its use in patients treated with antithrombotic drugs, and postoperative histological changes.

Complete polyp resection with cold snare versus hot snare polypectomy for polyps of 4-9 mm: a randomized controlled trial

BACKGROUND

Endoscopic screening with polypectomy reduces the incidence of colorectal cancer (CRC). Incomplete polyp removal may attenuate the effect of screening. This randomized trial compared cold snare polypectomy (CSP) with hot snare polypectomy (HSP) in terms of complete polyp resection.

METHODS

We included patients ≥ 40 years of age at eight hospitals in four countries who had at least one non-pedunculated polyp of 4-9 mm detected at colonoscopy. Patients were randomized 1:1 to CSP or HSP. Biopsies from the resection margins were obtained systematically after polypectomy in both groups. We hypothesized that CSP would be non-inferior to HSP, with a non-inferiority margin of 5 %. Logistic regression models were fitted to identify the factors explaining incomplete resection.

RESULTS

425 patients, with 601 polyps, randomized to either CSP or HSP were included in the analysis. Of 318 polyps removed by CSP and 283 polyps removed by HSP, 34 (10.7 %) and 21 (7.4 %) were incompletely resected, respectively, with an adjusted risk difference of 3.2 % (95 %CI -1.4 % to 7.8 %). There was no difference between the groups in terms of post-polypectomy bleeding, perforation, or abdominal pain. Independent risk factors for incomplete removal were serrated histology (odds ratio [OR] 3.96; 95 %CI 1.63 to 9.66) and hyperplastic histology (OR 2.52; 95 %CI 1.30 to 4.86) in adjusted analyses.

CONCLUSION

In this randomized trial, non-inferiority for CSP could not be demonstrated. Polyps with serrated histology are more prone to incomplete resection compared with adenomas. CSP can be used safely for small polyps in routine colonoscopy practice.

Risk Factors of Delayed Bleeding After Cold Snare Polypectomy for Colorectal Polyps: A Multicenter Study

BACKGROUND

Delayed bleeding (DB) rarely occurs after cold snare polypectomy (CSP) for colorectal polyps, but no large-scale studies have investigated this. The present study evaluated the rate, characteristics, and risk factors of DB of CSP.

METHODS

We conducted a multicenter retrospective study at 10 Japanese institutions. A total of 18,007 patients underwent CSP for colorectal polyps ≤ 10 mm in size from March 2015 to September 2019, and cases of DB (DB group) were analyzed for the rate, antithrombotic drugs, polyp size, morphology, location, and risk factors. As a control, 269 non-bleeding cases (non-DB group) with 606 polyps who underwent CSP at the same 10 facilities in the 2-week study period were extracted.

RESULTS

We analyzed 26 DB cases with 28 lesions, and the total DB rate was 0.14% (26/18,007). The DB group had significantly higher rates of using antiplatelets (42.3% vs. 13.0%, p < 0.001) and anticoagulants (19.2% vs. 2.6%, p = 0.002), and significantly higher rates of polyp size ≥ 5 mm (67.9% vs. 45.2%, p = 0.015), rectal lesion (25.0% vs. 6.6%, p = 0.003), and polypoid lesion (89.3% vs. 55.3%, p < 0.001) than the non-DB group. A multivariate analysis (odds ratio; 95% confidence interval) for patient characteristics showed antiplatelet use (4.521; 1.817-11.249, p = 0.001) and anticoagulant use (7.866; 20.63-29.988, p = 0.003) as independent risk factors for DB. Polyp size ≥ 5 mm (3.251; 1.417-7.463, p = 0.005), rectal lesion (3.674; 1.426-9.465, p = 0.007), and polypoid lesion (7.087; 20.81-24.132, p = 0.002) were also risk factors for lesion characteristics.

CONCLUSIONS

The rate of DB was 0.14% and antithrombotic drug use, polyp size, location, and morphology were related to it.

Preventing Postendoscopic Mucosal Resection Bleeding of Large Nonpedunculated Colorectal Lesions

The most common major adverse event of endoscopic mucosal resection (EMR) is clinically significant post-EMR bleeding (CSPEB), with an incidence of 6%-7% in large lesions. Repeat colonoscopy, blood transfusions, or other interventions are often needed. The associated direct costs are much higher than those of an uncomplicated EMR. In this review, we discuss the aspects related to CSPEB of large nonpedunculated polyps, such as risk factors, predictive models, and prophylactic measures, and we highlight evidence for preventive treatment options and explore new methods for bleeding prophylaxis. We also provide recommendations for steps that can be taken before, during, and after EMR to minimize bleeding risk. Finally, this review proposes future directions to reduce CSPEB incidence.

Endoscopic follow-up of mucosal defect after hot versus cold snare polypectomy in animal model

BACKGROUND AND AIM

Cold snare polypectomy (CSP) has received increasing attention in recent years, but few studies have assessed defect repair after polypectomy. Therefore, we compared the repair of mucosal defect after CSP and hot snare polypectomy (HSP) in a rabbit model.

METHODS

Resection of normal colonic mucosa using both HSP and CSP were performed in 40 male New Zealand white rabbits by an experienced endoscopist. Follow-up colonoscopy was performed after 7 and 15 days by another endoscopist. We assessed mucosal defect repair, status of healing, scar formation, and intraoperative or delayed complications (including perforation and bleeding).

RESULTS

Eight animals died of intraoperative or delayed perforation; follow-up colonoscopy was performed in 32 animals. On follow-up colonoscopy at 7 days after operation, 78.1% cases in the CSP group showed healing of mucosal defect compared with none in the HSP group (P < 0.001); mucosal repair score in the CSP group was significantly higher than HSP group (P < 0.001). On follow-up colonoscopy at 15 days, mucosal defect after CSP had completely healed in all cases (100%) versus 96.9% after HSP (P = 0.313). Among these healed defects, scar formation was observed in 2 of 32 cases in the CSP group compared with 19 of 31 in the HSP group (P < 0.001). Intraoperative perforation rate was significantly higher in the HSP group (15% vs 2.5%; P = 0.048).

CONCLUSIONS

Mucosal defect repair after CSP is quicker compared with HSP and is more likely to result in scarless healing. HSP is more likely to cause perforation in the thin colon walls.

A Pilot Randomized Trial of Polypectomy Techniques for 4 to 6 mm Colonic Polyps

BACKGROUND AND GOALS

There is variation in polypectomy techniques for resection of small polyps. Aim was to compare techniques for 4 to 6 mm polyps for recurrent adenoma, efficiency, and adverse events and to establish methodological factors for definitive trial.

MATERIALS AND METHODS

The study was a randomized controlled trial. Outpatients with ≥1, 4 to 6 mm polyps were randomized to cold forceps (CF), cold snare (CS), and hot snare (HS). Polypectomy site was marked with SPOT to assess for recurrence at the original polypectomy site during surveillance colonoscopy. To assess feasibility of a definitive trial we measured (1) rates of patient refusal, participation, ineligibility; (2) retention; (3) recurrent neoplasia; and (4) sample size for a definitive trial.

RESULTS

Three hundred fifty-three patients were randomized to 1 of the 3 polypectomy techniques, of whom 260 (73.6%) completed the initial colonoscopy (mean age 57 y, 50.4% women), with 91, 87, and 82 patients randomized to CF, CS, and HS polypectomy, respectively. Mean time for polyp resection for CF, CS, and HS were 198.8, 58.5, and 96.8 seconds, respectively, with CS and HS requiring less time than CF (P<0.001). One hundred sixty-four (63.1%) completed surveillance colonoscopy. Polyp recurrences were 9 (14.5%) with CF, 5 (9.6%) with CS, and 0 (0%) with HS. Although the recurrence relative risks with CF and CS polypectomy were 1.84 and 1.65 as compared with HS, respectively, neither was statistically significant.

CONCLUSIONS

CS and HS polypectomy require less time than CF. HS polypectomy may have a lower risk for recurrent neoplasia. High attrition rate is a challenge in conducting randomized controlled trial with polyp recurrence as endpoint.

Comparison of postpolypectomy bleeding events between cold snare polypectomy and hot snare polypectomy for small colorectal lesions: a large-scale propensity score-matched analysis

BACKGROUND AND AIMS

Cold snare polypectomy (CSP), a safe procedure for removing colon polyps, has a low prevalence of postpolypectomy bleeding (PPB). Previous studies have failed to demonstrate differences in PPB rates between CSP and hot snare polypectomy (HSP), possibly because of their small sample sizes. This study analyzed PPB rates after CSP and HSP.

METHODS

This was a retrospective analysis of colorectal lesions (diameter <10 mm) treated using endoscopic resection at our institution between January 2015 and December 2019. Resections were performed using CSP or HSP, depending on the endoscopist's preference. Endoscopic and histologic findings were recorded in the endoscopic database at our institution. Propensity score (PS) matching was performed to match patient age, lesion size, macroscopic features, location of the lesions, clipping after resection, and antithrombotic agent use. The CSP and HSP groups were compared to determine the adverse event (PPB) rates.

RESULTS

The CSP and HSP groups included 12,928 and 2408 lesions (total of 5371 patients), respectively. Univariate analysis revealed that the overall prevalence of PPB after HSP was higher than that after CSP (odds ratio [OR], 5.39; 95% confidence interval [CI], 2.50-11.60). After PS matching (2135 lesions per group), the prevalence of PPB after HSP remained higher than that after CSP (OR, 6.0; 95% CI, 1.34-26.8).

CONCLUSIONS

For colorectal lesions <10 mm in diameter, the risk of PPB after CSP is significantly lower than that after HSP, after PS matching. CSP for lesions <10 mm could be safely performed compared with HSP.

Snare devices with thinner loop wire may provide higher performance for cold snare polypectomy in an experimental model

Background and study aims  Snare devices play an important role in treatment of intestinal polyps. However, there are no objective measurements for the characteristics of the various types of snare devices. Materials and methods  Seven types of snare devices from four manufacturers were evaluated based on original measurements. The evaluated factors were stiffness, cutting quality, and change in force required for cutting depending on sheath shape. The latter two factors were evaluated by measuring the force required to cut 20 % gelatin cylinders, which simulated intestinal polyps. The cutting sharpness was evaluated by observing the sectional surface of cut gelatin cylinders using a stereomicroscope. The correlations between these measurements and characteristics of the snare devices were investigated. Results  A strong positive correlation, with an R 2 value of 0.863, was shown between the force required to cut gelatin cylinders and loop wire diameter. Loop wire diameter also had a strong correlation, with an R 2 value of 0.7997, with the change in force required for cutting gelatin cylinders depending on sheath shape. No correlations were detected between loop stiffness and characteristics of snare devices. The edge-enhanced image revealed that the rougher surfaces of the gelatin cylinders were cut by snares with a thicker diameter. Conclusions  Thinner loop wire may provide higher performance in cold snare polypectomy in an experimental model.

Guidelines for Colorectal Cold Polypectomy (supplement to "Guidelines for Colorectal Endoscopic Submucosal Dissection/Endoscopic Mucosal Resection")

The Japan Gastroenterological Endoscopy Society published the second edition of the "Guidelines for Colorectal Endoscopic Submucosal Dissection/Endoscopic Mucosal Resection" in 2019 to clarify the indications for colorectal endoscopic mucosal resection (EMR) and endoscopic submucosal dissection and to ensure appropriate preoperative diagnoses as well as effective and safe endoscopic treatment in front-line clinical settings. Endoscopic resection with electrocautery, including polypectomy and EMR, is indicated for colorectal polyps. Recently, the number of facilities introducing and implementing cold polypectomy without electrocautery has increased. Herein, we establish supplementary guidelines for cold polypectomy. Considering that the level of evidence for each statement is limited, these supplementary guidelines must be verified in clinical practice.

Polypectomy for Diminutive and Small Colorectal Polyps

Diminutive and small colorectal polyps are common findings during colonoscopies, and rarely contain dysplastic elements and progress to colorectal cancer. With improving technology and the advent of artificial intelligence, detection rates of small or diminutive polyps and adenomas are rising, resulting in increasing costs associated with colonoscopy. Incomplete resection rates are an outcome of interest because it correlates with interval colorectal cancer. More effort is warranted to standardize training programs and sensitize endoscopists to the importance of personal performance as a quality metric of colonoscopy. This article reviews indications, methods, and recent developments in polypectomy for small and diminutive polyps.

Cold versus hot endoscopic mucosal resection for large sessile colon polyps: a cost-effectiveness analysis

BACKGROUND : For large sessile colorectal polyps (LSCPs), endoscopic mucosal resection without diathermy ("cold endoscopic mucosal resection [EMR]") is gaining popularity because of its safety advantages over conventional EMR ("hot EMR"). Polyp recurrence rates have been reported to be higher with cold EMR. Considering these differences, we performed a cost-effectiveness analysis of these two techniques. METHODS : A decision analysis model was constructed for EMR of an LSCP. The decision tree incorporated the EMR method, clip use, procedural mortality, adverse events and their management, and polyp recurrence. Outcomes included days of lost productivity and marginal cost difference. Adverse event and recurrence rates were extracted from the existing literature, giving emphasis to recent systematic reviews and randomized controlled trials. RESULTS : Through 30 months of follow-up, the average cost of removing an LSCP by cold EMR was US$5213, as compared to $6168 by hot EMR, yielding a $955 cost difference (95 % confidence interval $903-$1006). Average days of lost productivity were 6.2 days for cold EMR and 6.3 days for hot EMR. This cost advantage remained over several analyses accounting for variations in recurrence rates and clip closure strategies. Clip cost and LSCP recurrence rate had the greatest and the least impacts on the marginal cost difference, respectively. CONCLUSION : Cold EMR is the dominant strategy over hot EMR, with lower cost and fewer days of lost productivity. In theory, a complete transition to cold EMR for LSCPs in the USA could result in an annual cost saving approaching US$7 million to Medicare beneficiaries.