Cold EMR of large sessile serrated polyps at colonoscopy (with video)

Cold snare polypectomy: A closer look at the efficacy and limitations for polyps 10-20 mm in size

Current guidelines recommend cold snare polypectomy for polyps less than 10 mm in size. Conversely, endoscopic mucosal resection is still the preferred technique for larger polyps. Concerns regarding cold snare polypectomy for larger polyps revolve around the difficulty in conducting en-bloc resection (resulting in piecemeal removal), and the potential for local residual polyp tissue and a high rate of recurrence. On the other hand, cold snare technique has the advantages of shortening procedure time, reducing delayed bleeding risks and lowering cost of treatment. Numerous ongoing and recent studies are focused on evaluating the risks and benefits of this technique for polyps larger than 10 mm, with the goal of providing clear guidelines in the near future. The aim of this editorial is to provide our readers with an overview regarding this subject and the latest developments surrounding it.

Efficacy and Safety of Cold Versus Hot Snare Endoscopic Mucosal Resection in Colorectal Polyp Removal: A Systematic Review and Meta-Analysis

BACKGROUND

Cold snare endoscopic mucosal resection (C-EMR) is hypothesized to offer a safety advantage over hot snare endoscopic mucosal resection (H-EMR). The primary objective of this meta-analysis is to evaluate the effectiveness and safety of C-EMR versus H-EMR for the management of colorectal lesions.

METHODS

A meta-analysis was performed to determine pooled odds ratios (ORs) for comparing outcomes between the C-EMR and H-EMR groups.

RESULTS

The pooled OR for complete resection rates were estimated at 0.70 (95% CI: 0.36-1.36, P =0.29) and en bloc rates were 0.24 (95% CI: 0.05-1.08, P=0.06) between C-EMR group and H-EMR group. The overall complete resection rate for C-EMR was 84%, and the en bloc resection rate was 57. Notably, C-EMR was associated with a significantly lower incidence of delayed bleeding. The recurrence rate of polyps was very low (2%) when treating sessile serrated polyp (SSP) lesions, but higher (23%) for non-SSP lesions. Subgroup analysis revealed minimal recurrence of polyps after using C-EMR for lesions between 10 to 20 mm and ≥20 mm.

CONCLUSIONS

This meta-analysis suggests that C-EMR could be a safer and equally effective alternative to H-EMR for resecting colorectal lesions. We recommend C-EMR as the preferred method for excising large colorectal lesions.

Cold Endoscopic Mucosal Resection (c-EMR) of Nonpedunculated Colorectal Polyps ≥20 mm: A Systematic Review and Meta-analysis

BACKGROUND

There is increasing evidence that cold endoscopic mucosal resection (c-EMR) can effectively treat large colorectal polyps. We aim to appraise the current literature and evaluate outcomes following c-EMR for nonpedunculated colonic polyps ≥20 mm.

METHODS

Major databases were searched. Primary outcomes included recurrence rate and adverse events. Meta-analysis was performed using a random-effects model.

RESULTS

Nine articles were included in the final analysis, which included 817 patients and 1077 colorectal polyps. Average polyp size was 28.8 (±5.1) mm. The pooled recurrence rate of polyps of any histology at 4 to 6 months was 21.0% (95% CI: 9.0%-32.0%, P <0.001, I2 =97.3, P <0.001). Subgroup analysis showed that recurrence was 10% for proximal lesions (95% CI: 0.0%-20.0%, P =0.054, I2 =93.7%, P =0.054) and 9% for distal lesions (95% CI: 2.0%-21.0%, P =0.114, I2 =95.8%, P =0.114). Furthermore, subgroup analysis showed that recurrence was 12% for adenoma (95% CI: 4.0%-19.0%, P =0.003, I2 =98.0%, P =0.003), and 3% for sessile serrated polyps (95% CI: 1.0%-5.0%, P =0.002, I2 =34.4%, P =0.002). Post-polypectomy bleeding occurred in 1% (n=8/817) of patients, whereas abdominal pain occurred in 0.2% (n=2/817) of patients.

CONCLUSIONS

C-EMR for nonpedunculated colorectal polyps ≥20 mm shows an excellent safety profile with a very low rate of delayed bleeding as well as significantly less recurrence for sessile serrated polyps than adenomas.

Endoscopic Resection of Neoplasia in the Lower GI Tract: A Clinical Algorithm

Background

Colorectal cancer is a highly prevalent malignancy and a significant driver of cancer mortality and health-related expenditure worldwide. Polyp removal reduces the incidence and mortality of colorectal cancer. In 2024, endoscopists have an array of resection modalities at their disposal. Each technique requires a unique skillset and has individual advantages and limitations. Consequently, resection in the colorectum requires an evidence-based algorithm approach that considers these factors.

Summary

A literature review of endoscopic resection for colonic neoplasia was conducted. Best supporting scientific evidence was summarized for the endoscopic resection of diminutive polyps, large ≥20 mm lesions and polyps containing invasive cancer. Factors including resection modality, complications and lesion selection were explored to inform an algorithm approach to colorectal resection.

Key Messages

Endoscopic resection in the colorectum is not a one-size-fits-all approach. Detailed understanding of polyp size, location, morphology and predicted histology are critical factors that inform appropriate endoscopic resection practice.

Cold versus hot snare endoscopic mucosal resection for large (≥15 mm) flat non-pedunculated colorectal polyps: a randomised controlled trial

BACKGROUND AND AIMS

Conventional hot snare endoscopic mucosal resection (H-EMR) is effective for the management of large (≥20 mm) non-pedunculated colon polyps (LNPCPs) however, electrocautery-related complications may incur significant morbidity. With a superior safety profile, cold snare EMR (C-EMR) of LNPCPs is an attractive alternative however evidence is lacking. We conducted a randomised trial to compare the efficacy and safety of C-EMR to H-EMR.

METHODS

Flat, 15-50 mm adenomatous LNPCPs were prospectively enrolled and randomly assigned to C-EMR or H-EMR with margin thermal ablation at a single tertiary centre. The primary outcome was endoscopically visible and/or histologically confirmed recurrence at 6 months surveillance colonoscopy. Secondary outcomes were clinically significant post-EMR bleeding (CSPEB), delayed perforation and technical success.

RESULTS

177 LNPCPs in 177 patients were randomised to C-EMR arm (n=87) or H-EMR (n=90). Treatment groups were equivalent for technical success 86/87 (98.9%) C-EMR versus H-EMR 90/90 (100%); p=0.31. Recurrence was significantly greater in C-EMR (16/87, 18.4% vs 1/90, 1.1%; relative risk (RR) 16.6, 95% CI 2.24 to 122; p<0.001).Delayed perforation (1/90 (1.1%) vs 0; p=0.32) only occurred in the H-EMR group. CSPEB was significantly greater in the H-EMR arm (7/90 (7.8%) vs 1/87 (1.1%); RR 6.77, 95% CI 0.85 to 53.9; p=0.034).

CONCLUSION

Compared with H-EMR, C-EMR for flat, adenomatous LNPCPs, demonstrates superior safety with equivalent technical success. However, endoscopic recurrence is significantly greater for cold snare resection and is currently a limitation of the technique.

TRIAL REGISTRATION NUMBER

NCT04138030.

Cold sub-mucosal injection versus traditional cold snare polypectomy for diminutive and small colorectal polyps: A systematic review and meta-analysis

BACKGROUND

The guidelines recommend conventional cold snare polypectomy (C-CSP) for diminutive and small colorectal polyps (≤ 10 mm). However, it remains unclear whether CSP with sub-mucosal injection (SI-CSP) achieves comparable efficacy to C-CSP for managing these lesions. This study compares SI-CSP with C-CSP for patients with diminutive and small colorectal polyps.

METHODS

An electronic literature search was conducted to retrieve articles comparing resection outcomes between SI-CSP and C-CSP in diminutive and small colorectal polyps (registration number INPLASY2023100096). Our primary outcomes of interest were the complete resection rate (CRR), complications (namely immediate bleeding, delayed bleeding and perforation) and polypectomy time. Mean differences with 95% confidence intervals (CI) were employed for continuous variables, while odds ratios (OR) with 95% CI were calculated for categorical variables. Data was analyzed using a random effects model and the I2 test was utilized to assess heterogeneity.

RESULTS

Eight studies involving 1470 patients with 2223 polyps were included in our analysis. The CRR was not significantly higher in the SI-CSP group, with an OR of 95% CI 0.50 (0.22, 1.15). The incidences of immediate bleeding (OR 95% CI 0.60 [0.26-1.40]) and delayed bleeding (OR 95% CI 0.88 [0.32-2.42]) did not differ significantly between the two groups. On average, the mean polypectomy time was 64.75 seconds shorter in the C-CSP group (95% CI, - 102.96 to - 26.53). Notably, no perforation events were reported in the included studies.

CONCLUSIONS

The use of SI-CSP was not superior to C-CSP in managing diminutive and small colorectal polyps and the procedure required significantly more time.

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.

Cold endoscopic mucosal resection versus cold snare polypectomy for colorectal lesions: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Cold resection of colorectal lesions is widely performed because of its safety and effectiveness; however, it remains uncertain whether adding submucosal injection could improve the efficacy and safety. We aimed to compare cold endoscopic mucosal resection (C-EMR) versus cold snare polypectomy (CSP) for colorectal lesions.

METHODS

We performed a systematic review of randomized controlled trials (RCTs) identified from PubMed, Cochrane Library, and Embase. The primary outcome was complete resection. Secondary outcomes were procedure time, en bloc resection, and adverse events (AEs). Prespecified subgroup analyses based on the size and morphology of the polyps were performed. The random-effects model was used to calculate the pooled risk ratio (RR) and mean difference, with corresponding 95%CIs, for dichotomous and continuous variables, respectively. Heterogeneity was assessed using the Cochran Q test and I 2 statistics.

RESULTS

7 RCTs were included, comprising 1556 patients, with 2287 polyps analyzed. C-EMR and CSP had similar risk ratios for complete resection (RR 1.02, 95%CI 0.98-1.07), en bloc resection (RR 1.08, 95%CI 0.82-1.41), and AEs (RR 0.74, 95%CI 0.41-1.32). C-EMR had a longer procedure time (mean difference 42.1 seconds, 95%CI 14.5-69.7 seconds). In stratified subgroup analyses, the risk was not statistically different between C-EMR and CSP for complete resection in polyps<10 mm or ≥10 mm, or for complete resection, en bloc resection, and AEs in the two groups among nonpedunculated polyps.

CONCLUSIONS

The findings of this meta-analysis suggest that C-EMR has similar efficacy and safety to CSP, but significantly increases the procedure time.

PROSPERO

CRD42023439605.

Comparison of cold snare polypectomy for sessile serrated lesions ≥10 mm between experienced and trainee endoscopists: A propensity score matching cohort study

Objectives

Previous studies of cold snare polypectomy (CSP) for sessile serrated lesions (SSLs) ≥10 mm were performed by experienced endoscopists, and therefore their skills might have significantly influenced results. In this study, we compared the efficacy and safety of CSP for SSLs ≥10 mm between experienced and trainee endoscopists.

Methods

In a 1:1 propensity score matched retrospective cohort study, we compared the complete resection rate, en-bloc resection rate, adverse event rate, and procedure time between experienced and trainee groups. Thirteen endoscopists performed CSP, and we defined the experienced group as endoscopists with board certification from the Japan Gastroenterological Endoscopy Society.

Results

We examined 616 lesions with SSLs ≥10 mm resected by CSP between February 2018 and May 2022. We excluded 61 lesions from the analysis because they had simultaneously undergone hot snare polypectomy (n = 57) or had been taken over by experienced endoscopists from trainees in the CSP procedure (n = 4). Finally, we identified 217 propensity score-matched pairs (n = 434). Between experienced and trainee groups, the results were complete resection rate (100 vs. 100%; p = 1.00), en-bloc resection rate (73.2 vs. 75.6%; p = 0.24), adverse event rate (3.2 vs. 2.8%; p = 0.77), or procedure time (6.2 vs. 5.9 min; p = 0.64).

Conclusions

We have demonstrated the safety and efficacy of CSP for SSLs ≥10 mm performed by experienced and trainee endoscopists.

Cold EMR vs. Hot EMR for the removal of sessile serrated polyps larger than 10 mm: a systematic review and meta-analysis

BACKGROUND

Endoscopic mucosal resection (EMR) appears to be a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. To assess the effectiveness and safety of EMR for removing SSPs ≥ 10 mm, we conducted this systematic review and meta-analysis.

METHODS

We conducted a thorough search of Embase, PubMed, Cochrane, and Web of Science databases for relevant studies reporting on EMR of SSPs ≥ 10 mm, up until December 2023. Our primary endpoints of interest were rates of technical success, residual SSPs, and adverse events (AE).

RESULTS

Our search identified 426 articles, of which 14 studies with 2262 SSPs were included for analysis. The rates of technical success, AEs, and residual SSPs were 100%, 2.0%, and 3.1%, respectively. Subgroup analysis showed that the technical success rates were the same for polyps 10-19 and 20 mm, and en-bloc and piecemeal resection. Residual SSPs rates were similar in en-bloc and piecemeal resection, but much lower in cold EMR (1.0% vs. 4.2%, P = 0.034). AEs rates were reduced in cold EMR compared to hot EMR (0% vs. 2.9%, P = 0.168), in polyps 10-19 mm compared to 20 mm (0% vs. 4.1%, P = 0.255), and in piecemeal resection compared to en-bloc (0% vs. 0.7%, P = 0.169).

CONCLUSIONS

EMR is an effective and safe technique for removing SSPs ≥ 10 mm. The therapeutic effect of cold EMR is superior to that of hot EMR, with a lower incidence of adverse effects.

PROSPERO REGISTRATION NUMBER

CRD42023388959.

Hybrid resection versus conventional resection for laterally spreading lesions of the papilla

BACKGROUND AND AIMS

Although conventional hot snare resection (CR) of laterally spreading lesions of the major papilla (LSL-Ps) is effective, it can be associated with delayed bleeding in upward of 25% of cases. Given the excellent safety profile of cold snare polypectomy in the colorectum, we investigated the efficacy and safety of a novel hybrid resection (HR) technique for LSL-P management, consisting of hot snare papillectomy plus cold snare resection of the laterally spreading component.

METHODS

A prospective cohort of patients underwent HR in a tertiary referral center over 60 months until December 2022. This cohort was compared with a historical cohort of patients who underwent CR at the same institution over 120 months until August 2017. The primary outcomes were recurrence and bleeding.

RESULTS

Twenty patients underwent HR (14 female; mean age 65.2 ± 12.2 years). Median lesion size was 30 mm (interquartile range, 25.0-47.5 mm). Recurrent or residual adenoma (RRA) was greater with HR (58.8% [n = 10] vs 29.8% [n = 14]; P = .034). The odds ratio for recurrence was 3.6 times (95% CI, 1.2-11.0) higher with HR (P = .027). RRA was multifocal in 4 (40%) and had a composite RRA volume >10 mm in 7 (70%). The median number of procedures required to treat RRA was higher with HR (4 vs 1, P = .002). There was no difference between CR and HR for intraprocedural bleeding (41.1% [n = 23] vs 25% [n = 5]; P = .587) or delayed bleeding (25.0% vs 10.0%, P = .211). There were no perforations.

CONCLUSIONS

The novel HR technique for LSL-P management is associated with a high rate of RRA that is recalcitrant to treatment, without mitigating the risk of intraprocedural or delayed bleeding. Therefore, CR should remain the mainstay management option for treating patients with an LSL-P. (Clinical trial registration number: NCT02306603.).

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.

A novel tool for case selection in endoscopic mucosal resection training

BACKGROUND

 As endoscopic mucosal resection (EMR) of large (≥ 20 mm) adenomatous nonpedunculated colonic polyps (LNPCPs) becomes widely practiced outside expert centers, appropriate training is necessary to avoid failed resection and inappropriate surgical referral. No EMR-specific tool guides case selection for endoscopists learning EMR. This study aimed to develop an EMR case selection score (EMR-CSS) to identify potentially challenging lesions for "EMR-naïve" endoscopists developing competency.

METHODS

 Consecutive EMRs were recruited from a single center over 130 months. Lesion characteristics, intraprocedural data, and adverse events were recorded. Challenging lesions with intraprocedural bleeding (IPB), intraprocedural perforation (IPP), or unsuccessful resection were identified and predictive variables identified. Significant variables were used to form a numerical score and receiver operating characteristic curves were used to generate cutoff values.

RESULTS

 Of 1993 LNPCPs, 286 (14.4 %) were in challenging locations (anorectal junction, ileocecal valve, or appendiceal orifice), 368 (18.5 %) procedures were complicated by IPB and 77 (3.9 %) by IPP; 110 (5.5 %) procedures were unsuccessful. The composite end point of IPB, IPP, or unsuccessful EMR was present in 526 cases (26.4 %). Lesion size, challenging location, and sessile morphology were predictive of the composite outcome. A six-point score was generated with a cutoff value of 2 demonstrating 81 % sensitivity across the training and validation cohorts.

CONCLUSIONS

 The EMR-CSS is a novel case selection tool for conventional EMR training, which identifies a subset of adenomatous LNPCPs that can be successfully and safely attempted in early EMR training.

Cold snare endoscopic mucosal resection for colon polyps: a systematic review and meta-analysis

BACKGROUND

 Cold snare endoscopic mucosal resection (CS-EMR) can reduce the risks associated with electrocautery during colon polyp resection. Data on efficacy are variable. This systematic review and meta-analysis aimed to estimate the pooled efficacy and safety rates of CS-EMR.

METHODS

 We conducted a comprehensive literature search of multiple databases, from inception to March 2023, for studies addressing outcomes of CS-EMR for colon polyps. The weighted pooled estimates with 95 %CIs were calculated using the random effects model. I2 statistics were used to evaluate heterogeneity.

RESULTS

 4137 articles were reviewed, and 16 studies, including 2592 polyps in 1922 patients (51.4 % female), were included. Overall, 54.4 % of polyps were adenomas, 45 % were sessile serrated lesions (SSLs), and 0.6 % were invasive carcinomas. Polyp recurrence after CS-EMR was 6.7 % (95 %CI 2.4 %-17.4 %, I2  = 94 %). The recurrence rate was 12.3 % (95 %CI 3.4 %-35.7 %, I2  = 94 %) for polyps ≥ 20 mm, 17.1 % (95 %CI 4.6 %-46.7 %, I2  = 93 %) for adenomas, and 5.7 % (95 %CI 3.2 %-9.9 %, I2  = 50 %) for SSLs. The pooled intraprocedural bleeding rate was 2.6 % (95 %CI 1.5 %-4.5 %, I2  = 51 %), the delayed bleeding rate was 1.5 % (95 %CI 0.8 %-2.7 %, I2  = 18 %), and no perforations or post-polypectomy syndromes were reported, with estimated rates of 0.6 % (95 %CI 0.3 %-1.3 %, I2  = 0 %) and 0.6 % (95 %CI 0.3 %-1.4 %, I2  = 0 %), respectively.

CONCLUSION

 CS-EMR demonstrated an excellent safety profile for colon polyps, with variable recurrence rates based on polyp size and histology. Large prospective studies are needed to validate these findings.

Cold Versus Hot Endoscopic Mucosal Resection for Sessile Serrated Colorectal Polyps ≥10 mm: A Systematic Review and Meta-analysis

INTRODUCTION

We performed a systematic review and meta-analysis studying the efficacy and safety of cold versus hot endoscopic mucosal resection (EMR) for resection of sessile serrated polyps (SSPs) ≥10 mm.

METHODS

Multiple databases were searched until January 2023 for studies reporting outcomes of cold versus hot EMR for SSPs ≥10 mm. The primary outcome was the residual SSP rate. Secondary outcomes included technical success rate, R0 resection rate, and adverse events. We used standard meta-analysis methods using the random-effects model, and I2% was used to assess heterogeneity.

RESULTS

Thirteen studies were included in the final analysis. In all, 1896 SSPs were included with a mean polyp size of 23.7 mm (range, 15.9 to 33). A total of 1452 SSPs were followed up for a median follow-up duration of 15.3 months (range, 6 to 37). The pooled residual SSP rate for cold EMR was 4.5% (95% CI: 1.0-17.4), and 5.1% (95% CI: 2.4-10.4) for hot EMR (P=0.9). The pooled rates of technical success, R0 resection, immediate bleeding, and perforation were comparable. Hot EMR was significantly associated with lower piecemeal resection (59.2% vs. 99.3%, P<0.001), higher en-bloc resection (41.4% vs. 1.4%, P<0.001), and delayed bleeding rate (4% vs. 0.7%, P=0.05) compared to cold EMR.

CONCLUSIONS

Cold EMR has similar efficacy compared to hot EMR for resection of SSP ≥ 10 mm, despite limitations in piecemeal R0 resection rate reporting. Although hot EMR was associated with a higher rate of en-bloc resection, it also showed an increased risk of delayed bleeding compared to cold EMR.

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.

Incomplete resection of colorectal polyps of 4-20 mm in size when using a cold snare, and its associated factors

BACKGROUND : Cold snare polypectomy (CSP) is increasingly used for polypectomy and is recommended as the first-line modality for small (< 10 mm) polyps. This study aimed to evaluate incomplete resection rates (IRRs) when using CSP for colorectal polyps of 4-20 mm. METHODS : Adults (45-80 years) undergoing screening, surveillance, or diagnostic colonoscopy and CSP by one of nine endoscopists were included. The primary outcome was the IRR for colorectal polyps of 4-20 mm, defined as the presence of polyp tissue in marginal biopsies after resection of serrated polyps or adenomas. Secondary outcomes included the IRR for serrated polyps, ease of resection, and complications. RESULTS:  413 patients were included (mean age 63; 48 % women) and 182 polyps sized 4-20 mm were detected and removed by CSP. CSP required conversion to hot snare resection in < 1 % of polyps of < 10 mm and 44 % of polyps sized 10-20 mm. The IRRs for polyps < 10 mm and ≥ 10 mm were 18 % and 21 %. The IRR was higher for serrated polyps (26 %) compared with adenomas (16 %). The IRR was higher for flat (IIa) polyps (odds ratio [OR] 2.9, 95 %CI 1.1-7.4); and when resection was judged as difficult (OR 4.2, 95 %CI 1.5-12.1), piecemeal resection was performed (OR 6.6, 95 %CI 2.0-22.0), or visible residual polyp was present after the initial resection (OR 5.4, 95 %CI 2.0-14.9). Polyp location, use of a dedicated cold snare, and submucosal injection were not associated with incomplete resection. Intraprocedural bleeding requiring endoscopic intervention occurred in 4.7 %. CONCLUSIONS : CSP for polyps of 4-9 mm is safe and feasible; however, for lesions ≥ 10 mm, CSP failure occurs frequently, and the IRR remains high even after technical success. Incomplete resection was associated with flat polyps, visual residual polyp, piecemeal resection, and difficult polypectomies.

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.

Curriculum for training in endoscopic mucosal resection in the colon: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

Endoscopic mucosal resection (EMR) is the standard of care for the complete removal of large (≥ 10 mm) nonpedunculated colorectal polyps (LNPCPs). Increased detection of LNPCPs owing to screening colonoscopy, plus high observed rates of incomplete resection and need for surgery call for a standardized approach to training in EMR. 1 : Trainees in EMR should have achieved basic competence in diagnostic colonoscopy, < 10-mm polypectomy, pedunculated polypectomy, and common methods of gastrointestinal endoscopic hemostasis. The role of formal training courses is emphasized. Training may then commence in vivo under the direct supervision of a trainer. 2 : Endoscopy units training endoscopists in EMR should have specific processes in place to support and facilitate training. 3: A trained EMR practitioner should have mastered theoretical knowledge including how to assess an LNPCP for risk of submucosal invasion, how to interpret the potential difficulty of a particular EMR procedure, how to decide whether to remove a particular LNPCP en bloc or piecemeal, whether the risks of electrosurgical energy can be avoided for a particular LNPCP, the different devices required for EMR, management of adverse events, and interpretation of reports provided by histopathologists. 4: Trained EMR practitioners should be familiar with the patient consent process for EMR. 5: The development of endoscopic non-technical skills (ENTS) and team interaction are important for trainees in EMR. 6: Differences in recommended technique exist between EMR performed with and without electrosurgical energy. Common to both is a standardized technique based upon dynamic injection, controlled and precise snare placement, safety checks prior to the application of tissue transection (cold snare) or electrosurgical energy (hot snare), and interpretation of the post-EMR resection defect. 7: A trained EMR practitioner must be able to manage adverse events associated with EMR including intraprocedural bleeding and perforation, and post-procedural bleeding. Delayed perforation should be avoided by correct interpretation of the post-EMR defect and treatment of deep mural injury. 8: A trained EMR practitioner must be able to communicate EMR procedural findings to patients and provide them with a plan in case of adverse events after discharge and a follow-up plan. 9: A trained EMR practitioner must be able to detect and interrogate a post-endoscopic resection scar for residual or recurrent adenoma and apply treatment if necessary. 10: Prior to independent practice, a minimum of 30 EMR procedures should be performed, culminating in a trainer-guided assessment of competency using a validated assessment tool, taking account of procedural difficulty (e. g. using the SMSA polyp score). 11: Trained practitioners should log their key performance indicators (KPIs) of polypectomy during independent practice. A guide for target KPIs is provided in this document.

Endoscopic mucosal resection using cold snare versus hot snare in treatment for 10-19 mm non-pedunculated colorectal polyps: protocol of a non-inferiority randomised controlled study

INTRODUCTION

Cold polypectomy has the advantages of simple operation, less time-consuming and fewer complications. Guidelines have recommended cold snare polypectomy (CSP) to resect small polyps sized ≤5 mm and sessile polyps sized 6-9 mm. However, evidence is scarce regarding cold resection for non-pedunculated polyps sized ≥10 mm. Cold snare endoscopic mucosal resection (CS-EMR) combining CSP and submucosal injection was designed to improve the complete resection rate and reduce adverse events. We hypothesise that CS-EMR is non-inferior to conventional hot snare endoscopic mucosal resection (HS-EMR) in the resection of 10-19 mm non-pedunculated colorectal polyps.

METHODS AND ANALYSIS

This study is a prospective, randomised, open-label, non-inferiority, single-centre trial. Outpatients scheduled to undergo a colonoscopy and present eligible polyps will be randomised to receive either CS-EMR or HS-EMR. The primary endpoint is the complete resection. Considering that HS-EMR of 10-19 mm colorectal polyps will yield a complete resection rate of at least 92% and a non-inferiority margin of -10%, a total of 232 polyps will be included (one-sided α, 2.5%; β, 20%). The analyses are intended to evaluate first non-inferiority (lower limit 95% CI greater than -10% for group difference) and then superiority (lower limit 95% CI>0%) if non-inferiority is achieved. Secondary endpoints include en-bloc resection, the occurrence of adverse events, the use of endoscopic clips, resection time and cost.

ETHICS AND DISSEMINATION

The study has been approved by the institutional review board of the Peking Union Medical College Hospital (No. K2203). All participants in the trial will provide written informed consent. The results of this trial will be published in an open-access way.

TRIAL REGISTRATION NUMBER

NCT05545787.

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.

Incomplete resection rates of 4- to 20-mm non-pedunculated colorectal polyps when using wide-field cold snare resection with routine submucosal injection

Background and study aims  Incomplete resection of 4- to 20-mm colorectal polyps occur frequently (> 10 %), putting patients at risk for post-colonoscopy colorectal cancer. We hypothesized that routine use of wide-field cold snare resection with submucosal injection (CSP-SI) might reduce incomplete resection rates (IRRs). Patients and methods  Patients aged 45 to 80 years undergoing elective colonoscopies were enrolled in a prospective clinical study. All 4- to 20-mm non-pedunculated polyps were resected using CSP-SI. Post-polypectomy margin biopsies were obtained to determine IRRs through histopathology assessment. The primary outcome was IRR, defined as remnant polyp tissue found on margin biopsies. Secondary outcomes included technical success and complication rates. Results  A total of 429 patients (median age 65 years, 47.1 % female, adenoma detection rate 40 %) with 204 non-pedunculated colorectal polyps 4 to 20 mm removed using CSP-SI were included in the final analysis. CSP-SI was technical successful in 97.5 % (199/204) of cases (5 conversion to hot snare polypectomy). IRR for CSP-SI was 3.8 % (7/183) (95 % confidence interval [CI] 2.7 %-5.5 %). IRR was 1.6 % (2/129), 16 % (4/25), and 3.4 % (1/29) for adenomas, serrated lesions, and hyperplastic polyps respectively. IRR was 2.3 % (2/87), 6.3 % (4/64), 4.0 % (6/151), and 3.1 % (1/32) for polyps 4 to 5 mm, 6 to 9 mm, < 10 mm, and 10 to 20 mm, respectively. There were no CSP-SI-related serious adverse events. Conclusions  Use of CSP-SI results in lower IRRs compared to what has previously been reported in the literature for hot or cold snare polypectomy when not using wide-field cold snare resection with submucosal injection. CSP-SI showed an excellent safety and efficacy profile, however comparative studies to CSP without SI are required to confirm these results.

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.

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.

Cold snare polypectomy versus cold endoscopic mucosal resection for small colorectal polyps: a multicenter randomized controlled trial

BACKGROUND

Cold snare polypectomy (CSP) is recommended for the resection of small colorectal polyps. However, few studies have investigated the efficacy of cold endoscopic mucosal resection (cold EMR) for small polyps. Thus, the aim of this study was to investigate the efficacy and safety of cold EMR compared with CSP for small colorectal polyps.

METHODS

This was a multicenter, randomized trial conducted in three tertiary centers from January 2018 to February 2021. Patients with polyps sized 6-10 mm were randomized to CSP or cold EMR group. After polypectomy, two additional biopsies were performed to assess the completeness of resection. The primary outcome was complete polyp resection rate. Secondary outcomes were total procedure time and rate of adverse events such as immediate bleeding, delayed bleeding, and perforation.

RESULTS

A total of 444 polyps in 327 patients were assessed and randomly assigned to each group. Of those, 425 polyps were finally analyzed based on pathology results. The complete resection rate was not significantly different between cold EMR and CSP groups (91.9% vs 89.8%, p = 0.24). However, the total procedure time was significantly increased in cold EMR (87.6 s vs. 45.8 s, p < 0.001). The rate of polypectomy adverse events was not significantly different between the two groups. No patient had massive bleeding or perforation.

CONCLUSIONS

There was no difference in complete resection rate or adverse events between CSP and cold EMR. However, CSP reduced the total procedure time.

Efficacy and safety of cold snare polypectomy for sessile serrated polyps ≥ 10 mm: A systematic review and meta-analysis

BACKGROUND

Cold snare polypectomy (CSP) is a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. However, the efficacy and safety of this technique remain undetermined.

AIMS

We aimed to comprehensively evaluate the efficacy and safety of CSP for SSPs ≥ 10 mm.

METHODS

PubMed, EMBASE, Web of Science and Cochrane Library were searched up to January 2021.

RESULTS

A total of 10 studies consisting of 1727 SSPs (range, 10-40 mm) from 1021 patients were included. The overall rates of technical success, adverse events (AEs) and residual SSPs were 100%, 0.7% and 2.9%, respectively. Subgroup analysis showed that the rates of technical success and AEs were comparable between CSP and cold endoscopic mucosal resection (EMR) (99.9% vs. 100% and 1.3% vs. 0.5%, respectively), between the proximal and distal colon (100% vs. 99.9% and 0.3% vs. 0, respectively), and between polyps of 10-19 mm and ≥20 mm (99.8% vs. 100% and 0.9% vs. 0, respectively). However, subgroup analysis showed that the rate of residual SSPs was slightly lower in CSP compared with cold EMR (1.3% vs. 3.9%), as well as in polyps of 10-19 mm compared with those ≥20 mm (3.1% vs. 4.7%).

CONCLUSION

CSP was an effective and safe technique for removing SSPs ≥ 10 mm.

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.

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

BACKGROUND

Complete 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.

AIM

To analyze LRR of large colonic polyps in a systematic review and meta-analysis.

METHODS

MEDLINE, 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.

RESULTS

Six 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).

CONCLUSION

LRR 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.

Clip Closure Does Not Reduce Risk of Bleeding After Resection of Large Serrated Polyps: Results From a Randomized Trial

BACKGROUND & AIMS

Serrated polyps are important colorectal cancer precursors and are most commonly located in the proximal colon, where post-polypectomy bleeding rates are higher. There is limited clinical trial evidence to guide best practices for resection of large serrated polyps (LSPs).

METHODS

In a multicenter trial, patients with large (≥20 mm) non-pedunculated polyps undergoing endoscopic mucosal resection (EMR) were randomized to clipping of the resection base or no clipping. This analysis is stratified by histologic subtype of study polyp(s), categorized as serrated [sessile serrated lesions (SSLs) or hyperplastic polyps (HPs)] or adenomatous, comparing clip vs control groups. The primary outcome was severe post-procedure bleeding within 30 days of colonoscopy.

RESULTS

A total of 179 participants with 199 LSPs (191 SSLs and 8 HPs) and 730 participants with 771 adenomatous polyps were included in the study. Overall, 5 patients with LSPs (2.8%) experienced post-procedure bleeding compared with 42 (5.8%) of those with adenomas. There was no difference in post-procedure bleeding rates between patients in the clip vs control group among those with LSPs (2.3% vs 3.3%, respectively, difference 1.0%; P = NS). However, among those with adenomatous polyps, clipping was associated with a lower risk of post-procedure bleeding (3.9% vs 7.6%, difference 3.7%; P = .03) and overall serious adverse events (5.5% vs 10.6%, difference 5.1%; P = .01).

CONCLUSION

The post-procedure bleeding risk for LSPs removed via EMR is low, and there is no discernable benefit of prophylactic clipping of the resection base in this group. This study indicates that the benefit of endoscopic clipping following EMR may be specific for >2 cm adenomatous polyps located in the proximal colon.

CLINICALTRIALS

gov, Number: NCT01936948.

Repeat Cold Snare Polypectomy Can Be Performed for Recurrent Benign Lesions After Cold Snare Polypectomy

BACKGROUND AND AIMS

Recurrence after cold snare polypectomy (CSP) sometimes occurs. We assessed the feasibility of repeat CSP for recurrence after CSP.

METHODS

We retrospectively reviewed recurrent lesions after CSP which were resected by repeat CSP from 2016 to 2021 in our institution and analyzed clinical outcomes of repeat CSP, comparing those of non-recurrent 454 lesions receiving standard CSP in 2016 and follow-up colonoscopy. We also analyzed the recurrent rate among cases receiving follow-up in both groups. Indication of repeat CSP was lesions diagnosed as benign tumors of ≤ 10 mm.

RESULTS

We analyzed 80 lesions receiving repeat CSP. The polyp size (mean ± standard deviation: SD) was 4.1 ± 2.3 mm (range 2-10 mm). The right-sided colon and non-polypoid morphology rates were 66.3% and 43.8%, respectively. Histopathological diagnosis was 66 adenomas, 12 sessile serrated lesions (SSLs), 1 SSL with dysplasia, and 1 high-grade dysplasia. The procedure time (min, mean ± SD) of repeat CSP was 0.9 ± 0.8. Regarding the comparison of repeat CSP/ standard CSP group, the en bloc resection and histopathological complete resection rates were 78.8%/ 98.0% (p < 0.001) and 43.8%/59.6% (p = 0.007) and the rates of perioperative hemorrhage requiring endoscopic clipping were 1.3%/ 1.0% (p = 0.646). There were no postoperative hemorrhage and perforation in both groups (p = 1.0). Among lesions receiving follow-up colonoscopy, the mean recurrence rates (number, median follow-up period: interquartile) of repeat CSP and standard CSP group were 2.0% (1/50, 12 months: 12-24) versus 0.7% (3/454, 12 months: 12-24) (p = 0.862).

CONCLUSIONS

Repeat CSP for benign recurrent lesions after CSP was safe and feasible.

Safety and effectiveness of underwater cold snare resection without submucosal injection of large non-pedunculated colorectal lesions

Background and study aims  Adverse events are uncommon with cold snaring, but cold techniques are generally reserved for lesions ≤ 9 mm out of concern for incomplete resection or inability to mechanically resect larger lesions. In a non-distended, water-filled lumen, colorectal lesions are not stretched, enabling capture and en bloc resection of large lesions. We assessed the effectiveness and safety of underwater cold snare resection (UCSR) without submucosal injection (SI) of ≥ 10 mm non-pedunculated, non-bulky (≤ 5 mm elevation) lesions with small, thin wire snares. Patients and methods  Retrospective analysis of an observational cohort of lesions removed by UCSR during colonoscopy. A single endoscopist performed procedures using a small thin wire (9-mm diameter) cold or (10-mm diameter) hybrid snare. Results  Fifty-three lesions (mean 15.8 mm [SD 6.9]; range 10-35 mm) were removed by UCSR from 44 patients. Compared to a historical cohort, significantly more lesions were resected en bloc by UCSR (84.9 % [45/53]; P  = 0.04) compared to conventional endoscopic mucosal resection (EMR) (64.0 % [32/50]). Results were driven by high en bloc resection rates for 10- to 19-mm lesions (97.3 % [36/37]; P  = 0.01). Multiple logistic regression analysis adjusted for potential confounders showed en bloc resection was significantly associated with UCSR compared to conventional EMR (OR 3.47, P  = 0.027). Omission of SI and forgoing prophylactic clipping of post-resection sites did not result in adverse outcomes. Conclusions  UCSR of ≥ 10 mm non-pedunculated, non-bulky colorectal lesions is feasible with high en bloc resection rates without adverse outcomes. Omission of SI and prophylactic clipping decreased resource utilization with economic benefits. UCSR deserves further evaluation in a prospective comparative study.

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.

High-Quality Colonoscopy: A Review of Quality Indicators and Best Practices

Colorectal cancer (CRC) continues to be the third leading cause of cancer-related deaths in the US. Colonoscopy remains the best preventative tool against the development of CRC. As a result, high-quality colonoscopy is becoming increasingly important. Specifically, recent guidelines have highlighted pre-procedural, peri-procedural, and post-procedural practices, which promise to improve patient outcomes and reduce the mortality and interval cancer rates in patients undergoing colonoscopies. Despite the guidelines and advances in modern endoscopy, the procedure remains provider-dependent, which results in differences in outcomes. As a result, incorporating high-quality colonoscopy approaches early in training is key to improving patient outcomes. Additionally, ensuring that high-quality colonoscopy is practiced widely by endoscopists can lead to the most cost-effective care.

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.

Polypectomy for Large Polyps with Endoscopic Mucosal Resection

Beginning in 1955, when the saline injection was first described to prevent transmural injury during polyp fulguration, endoscopic mucosal resection (EMR) has grown exponentially, both in scope and in practice. Because EMR is an organ-preserving technique even for large polyps, this allows for comparable outcomes to surgery, but substantially improved cost savings and significantly reduced morbidity and mortality. To achieve this, however, one must master the 4 fundamental components that are critical to the success of EMR- time, team, tools, and technique. This article aims to provide a compendium of state of the art updates within the field of endoluminal resection.

Risk Stratification of Endoscopic Submucosal Dissection in Colon Tumors

Background: Endoscopic submucosal dissection (ESD) is a technique proven effective in the treatment of early neoplastic lesions in the gastrointestinal tract. However, in the case of colon lesions, many doubts remain. The purpose of our study is to stratify the success rates of the ESD procedure in the colon. Materials and Methods: A retrospective analysis of 601 patients who underwent ESD procedure for colorectal neoplasm from 2016 to 2019 in Center of Bowel Treatment, Brzeziny, Poland. Excluding 335 rectal neoplasms, we selected 266 patients with lesions located in the colon. Results: Lesions located in the left colon were characterized by the statistically higher en bloc resection and success rate, compared with the right colon—87.76% vs. 73.95% (p = 0.004) and 83.67% vs. 69.75% (p = 0.007), respectively. The success rate was significantly lower in lesions with submucosal cancer, compared to low- and high-grade dysplasia (p < 0.001). Polyps located in the right colon were characterized by a slightly higher complication rate compared to the left colon, without statistical significance—13.45% vs. 9.52% (p = 0.315). Conclusions: Our results show that colonic ESD has a high success rate, especially in the left colon, with a low risk of complications, slightly higher than in the right colon.

Minimally Invasive Endoscopic and Surgical Management of Rectal Neoplasia

Rectal cancer demonstrates a characteristic natural history in which benign rectal neoplasia precedes malignancy. The worldwide burden of rectal cancer is significant, with rectal cancer accounting for one-third of colorectal cancer cases annually. The importance of early detection and successful management is essential in decreasing its clinical burden. Minimally invasive treatment of rectal neoplasia has evolved over the past several decades, which has led to reduced local recurrence rates and improved survival outcomes. The approach to diagnosis, staging, and selection of appropriate treatment modalities is a multidisciplinary effort combining interventional endoscopy, surgery, and radiology tools. This review examines the currently available minimally invasive endoscopic and surgical management options of rectal neoplasia.

Safety and Efficacy of Cold Snare Polypectomy Without Submucosal Injection for Large Sessile Serrated Lesions: A Prospective Study

BACKGROUND & AIMS

Cold snare polypectomy (CSP) has become the standard resection method for small colorectal polyps (<10 mm). Sessile serrated lesions (SSL) have low prevalence of advanced histology irrespective of size, and thus could be amenable to CSP. In this study, we evaluated the safety and efficacy of CSP for SSLs ≥10 mm.

METHODS

Between November 2018 and January 2020, we prospectively enrolled 300 consecutive patients who underwent CSP for 474 SSLs ≥10 mm. To delineate SSL borders, indigo carmine chromoendoscopy and/or image-enhanced endoscopy was conducted. Piecemeal CSP (pCSP) was performed in cases where en-bloc resection was difficult. Biopsy specimens were obtained from the margins of the post-polypectomy defect to confirm complete resection. Surveillance colonoscopy was performed to screen for local recurrence.

RESULTS

All lesions were successfully resected using CSP without submucosal injection. The median diameter of the resected lesions was 14 mm, and pCSP was used to resect 106 (22%) lesions. Post-polypectomy biopsies revealed residual serrated tissue in only one case (0.2%). Adverse events included immediate bleeding in 8 (3%) patients; no delayed bleeding events occurred, irrespective of the use of antithrombotic drugs. During a 7-month median follow-up period, surveillance colonoscopies were performed for 384 lesions (81%), and no local recurrences were detected.

CONCLUSIONS

CSP without submucosal injection is a safe and effective treatment for SSLs ≥10 mm. UMIN Clinical Trials, Number: UMIN000034763.

Endoscopic Management of Complex Colorectal Polyps: Current Insights and Future Trends

Most colorectal cancers arise from adenomatous polyps and sessile serrated lesions. Screening colonoscopy and therapeutic polypectomy can potentially reduce colorectal cancer burden by early detection and removal of these polyps, thus decreasing colorectal cancer incidence and mortality. Most endoscopists are skilled in detecting and removing the vast majority of polyps endoscopically during a routine colonoscopy. Polyps can be considered “complex” based on size, location, morphology, underlying scar tissue, which are not amenable to removal by conventional endoscopic polypectomy techniques. They are technically more challenging to resect and carry an increased risk of complications. Most of these polyps were used to be managed by surgical intervention in the past. Rapid advancement in endoscopic resection techniques has led to a decreasing role of surgery in managing these complex polyps. These endoscopic resection techniques do require an expert in the field and advanced equipment to perform the procedure. In this review, we discuss various advanced endoscopic techniques for the management of complex polyps.

Irrigating Acetic Acid Solution During Colonoscopy for the Detection of Sessile Serrated Neoplasia: A Randomized Controlled Trial

BACKGROUND

Misdiagnosed sessile serrated lesions (SSLs) are important precursors for interval colorectal cancers.

AIMS

We investigated the usage of acetic acid (AA) solution for improving the detection of SSLs in the right colon in a randomized controlled trial.

METHODS

A tandem observation of the right colon was performed in 412 consecutive patients. A first inspection was performed under white light high-definition endoscopy. In the AA group, a low concentration vinegar solution (AA: 0.005%) irrigated by a water pump in the right colon was compared with a plain solution of normal saline (NS) in the diagnostic yield of SSLs during the second inspection. Secondary outcomes in overall polyp detection were measured.

RESULTS

Qualitative comparisons showed significant differences in the detection rates of all polyps except adenomas, with remarkable improvement in the demonstration of advanced (> 20 mm), SSLs, and hyperplastic polyps during the second inspection of the right colon using the AA solution. Significant improvement was also noted in the AA group, as far as the mean number of polyps/patient detected, not only in SSLs (AA group: 0.14 vs. NS group: 0.01, P < 0.001), but also in all histological types and all size-categories in the right colon. Small (≤ 9 mm) polyps were detected at a higher rate in the sigmoid colon expanding the effect of the method in the rest of the colon.

CONCLUSION

AA-assisted colonoscopy led to a significant increase in SSLs detection rate in the right colon in a safe, quick, and effective manner.

A Randomized Controlled Trial of Cold Snare Polypectomy Technique: Technique Matters More Than Snare Wire Diameter

INTRODUCTION

Cold snare polypectomy (CSP) is safe and effective for the removal of small adenomas (≤10 mm); however, reported incomplete resection rates (IRRs) vary. The optimal CSP technique, where a wide margin of normal tissue is resected around the target lesion, and snare design have both been hypothesized to reduce the IRR after CSP. We sought to investigate the efficacy of a thin-wire versus thick-wire diameter snare on IRR, using the standardized CSP technique.

METHODS

This was an international multicenter parallel design randomized trial with 17 endoscopists of varying experience (NCT02581254). Patients were randomized in a 1:1 ratio to the use of a thin-wire (0.30 mm) or thick-wire (0.47 mm) snare for CSP of small (≤10 mm) colorectal polyps. The primary end point was the IRR as determined by the histologic assessment of the defect margin after polypectomy.

RESULTS

Over 52 months to January 2020, 1,393 patients were eligible. A total of 660 patients with polyps (57.4% male) were randomized to a thin-wire (n = 339) or thick-wire (n = 321) snare. The overall IRR of the cohort was 1.5%. There was no significant difference in the IRR between the thin- and thick-wire arms; relative risk-0.41, 95% CI (0.11-1.56), P = 0.21. No significant differences were observed in the rate of adverse events.

DISCUSSION

In this multicenter randomized trial, CSP is safe and effective with very low rates of incomplete resection independent of the diameter of the snare wire used. This suggests that the optimal operator technique is more important than the snare design alone in minimizing residual adenoma after CSP.

Safety and efficacy of cold versus hot snare polypectomy including colorectal polyps ≥1 cm in size

Cold snare polypectomy (CSP; polypectomy without electrocautery) has spread rapidly worldwide during the past decade in what has been called "Cold Revolution". We performed a PubMed literature search for studies investigating CSP outcomes for colorectal polyps. Five randomized controlled trials (RCTs) assessed the complete resection rates (CRRs). The CRRs were similar regardless of the presence or absence of electrocautery, and the efficacy of submucosal injection for better CRRs is still controversial. Eight RCTs assessed the adverse events. The incidence of intraprocedural bleeding with cold procedures was comparable to or higher than that of hot procedures. The incidences of delayed bleeding were comparable to or lower with cold procedures, especially in patients taking anticoagulants. Fifteen studies have been reported on CSP for large (≥1 cm) colorectal polyps (10 retrospective studies, four prospective single-arm studies, and one prospective RCT). These studies reported that the safe cold procedures (a low intra- and post-procedural bleeding rate without perforation) could be implemented for lesions ≥1 cm. However, considering the incision depth of CSP and the local recurrence rate based on the current evidence, only large sessile serrated lesions (SSLs) can be candidates for cold procedures, and large adenomas should not be candidates for this procedure. Based on the current evidence, CSP seems to be the appropriate standard procedure for sub-centimeter colorectal low-grade adenomas due to its safety and simplicity. Thus, large SSLs can be candidates for cold procedures; however, careful inspection and further prospective studies are warranted to confirm the procedure's clinical relevance.

Large polyps: Pearls for the referring and receiving endoscopist

Polyps are precursors to colorectal cancer, the third most common cancer in the United States. Large polyps, i.e.,, those with a size ≥ 20 mm, are more likely to harbor cancer. Colonic polyps can be removed through various techniques, with the goal to completely resect and prevent colorectal cancer; however, the management of large polyps can be relatively complex and challenging. Such polyps are generally more difficult to remove en bloc with conventional methods, and depending on level of expertise, may consequently be resected piecemeal, leading to an increased rate of incomplete removal and thus polyp recurrence. To effectively manage large polyps, endoscopists should be able to: (1) Evaluate the polyp for characteristics which predict high difficulty of resection or incomplete removal; (2) Determine the optimal resection technique (e.g., snare polypectomy, endoscopic mucosal resection, endoscopic submucosal dissection, etc.); and (3) Recognize when to refer to colleagues with greater expertise. This review covers important considerations in this regard for referring and receiving endoscopists and methods to best manage large colonic polyps.

Modified endoscopic mucosal resection techniques for treating precancerous colorectal lesions

Endoscopic mucosal resection (EMR) is a technique allowing efficacious and minimally invasive resection of precancerous lesions across the entire gastrointestinal tract. However, conventional EMR, involving injection of fluid into the submucosal space, is imperfect, given the high rate of recurrence of post-endoscopic resection adenoma, especially after piecemeal resection. In light of these observations, modifications of the technique have been proposed to overcome the weakness of conventional EMR. Some of them were designed to maximize the chance of en bloc resection—cap-assisted EMR, underwater EMR, tip-in EMR, precutting, assisted by ligation device—while others were designed to minimize the complications (cold EMR). In this review, we present their modes of action and summarize the evidence regarding their efficacy and safety.

Piecemeal cold snare polypectomy versus conventional endoscopic mucosal resection for large sessile serrated lesions: a retrospective comparison across two successive periods

OBJECTIVE

Large (≥20 mm) sessile serrated lesions (L-SSL) are premalignant lesions that require endoscopic removal. Endoscopic mucosal resection (EMR) is the existing standard of care but carries some risk of adverse events including clinically significant post-EMR bleeding and deep mural injury (DMI). The respective risk-effectiveness ratio of piecemeal cold snare polypectomy (p-CSP) in L-SSL management is not fully known.

DESIGN

Consecutive patients referred for L-SSL management were treated by p-CSP from April 2016 to January 2020 or by conventional EMR in the preceding period between July 2008 and March 2016 at four Australian tertiary centres. Surveillance colonoscopies were conducted at 6 months (SC1) and 18 months (SC2). Outcomes on technical success, adverse events and recurrence were documented prospectively and then compared retrospectively between the subsequent time periods.

RESULTS

A total of 562 L-SSL in 474 patients were evaluated of which 156 L-SSL in 121 patients were treated by p-CSP and 406 L-SSL in 353 patients by EMR. Technical success was equal in both periods (100.0% (n=156) vs 99.0% (n=402)). No adverse events occurred in p-CSP, whereas delayed bleeding and DMI were encountered in 5.1% (n=18) and 3.4% (n=12) of L-SSL treated by EMR, respectively. Recurrence rates following p-CSP were similar to EMR at 4.3% (n=4) versus 4.6% (n=14) and 2.0% (n=1) versus 1.2% (n=3) for surveillance colonoscopy (SC)1 and SC2, respectively.

CONCLUSIONS

In a historical comparison on the endoscopic management of L-SSL, p-CSP is technically equally efficacious to EMR but virtually eliminates the risk of delayed bleeding and perforation. p-CSP should therefore be considered as the new standard of care for L-SSL treatment.