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

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.

Cold Snare Polypectomy in Pediatric Polyposis: A Multicenter Experience

Background: Cold snare polypectomy (CSP) is a well-established and recommended technique in adult gastroenterology for the safe, efficient and complete removal of nonpedunculated lesions up to 10 mm, with piecemeal excision possible for larger lesions. However, the application of CSP in pediatric patients remains underexplored. This study summarizes a multicenter experience of CSP in pediatric polyposis patients, focusing on safety, efficacy and clinical outcomes. Methods: This retrospective study was conducted at two pediatric tertiary centers, encompassing patients aged 1 to 21 years with polyposis who underwent colonoscopy with CSP and hot snare polypectomy (HSP) between January 2022 and January 2023. Patient demographics, procedure characteristics, polyp details and clinical outcomes were analyzed. Results: A total of 477 CSPs were performed in 63 colonoscopies. Satisfactory bowel preparation was noted in 79% of procedures, with a pooled mean procedure duration of 52 min and cecal intubation achieved in 98%. Polyps resected by CSP ranged from 3 to 70 mm in size and were predominantly left-sided. Tissue retrieval was complete in 94% of cases and partial in 5%. Mild intraprocedural bleeding occurred in 25% of CSP cases, requiring endoclip placement in 19%, with no post-procedural bleeding or significant complications observed. Comparatively, CSP demonstrated favorable bleeding rates relative to HSP. At two-week follow-up, four patients required emergency evaluation for unrelated complaints, but with no adverse events attributed to CSP. Conclusions: CSP is a safe and effective technique for the removal of sessile polyps in pediatric patients with polyposis. Mild intraprocedural bleeding, when observed, was effectively managed with standard hemostatic techniques. These findings support the potential of CSP as a preferred modality for sessile polyp removal in pediatric patients, though further research is warranted to define its role across broader pediatric populations and practice settings.

Effectiveness and safety of thin vs. thick cold snare polypectomy of small colorectal polyps: Systematic review and meta-analysis

Background and study aims Cold-snare polypectomy (CSP) is considered the standard of care for resection of colorectal polyps ≤10 mm. Data on the efficacy of CSP performed with thin-wire snares compared0 with thick-wire snares are conflicting. We performed a meta-analysis comparing complete resection (CR) and adverse event rates of CSP using thin-wire and thick-wire snares. Patients and methods Comparative studies of adult patients with ≧1 colorectal polyp(s) ≦10 mm who underwent CSP with thin-wire or thick-wire snares were included. We collected data on study, patient, polyp, and snare characteristics. The primary outcome was CR rate. Secondary outcomes were polyp retrieval rate, intraprocedural bleeding, delayed post-polypectomy bleeding, deep mural injury or perforation, patient discomfort, total sedation, and procedure time. We used random-effects models to calculate risk ratios for outcomes. We performed risk of bias assessments, rated the certainty of evidence, and assessed publication bias for all studies. Results We included four randomized controlled trials (RCTs) and two observational studies including 1316 patients with 1679 polyps (826 thin-wire CSPs and 853 thick-wire CSPs). There was no significant difference between thin-wire CSP (92.1%) and thick-wire CSP (87.7%) for RCTs (risk ratio [RR] 1.05, 95% confidence interval [CI] 0.94-1.16) or observational studies (78.1% versus 79.6%, RR 1.03, 95% CI 0.99-1.08). There were no significant differences in polyp retrieval rate or intraprocedural bleeding. There were no cases of delayed bleeding or perforation. Conclusions We found no differences in CR rates for CSP between thin-wire and thick-wire snares. CSP, regardless of snare type, is safe and effective for resection of small colorectal polyps.

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 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.

Comparison of complete resection rates in cold snare polypectomy using two different wire diameter snares: A randomized controlled study

BACKGROUND AND AIM

Cold snare polypectomy (CSP) is a standard treatment for small colorectal polyps. This study examined the effect of different snare wire diameters on complete histological resection rate, resection depth, and CSP safety.

METHODS

This randomized controlled trial was conducted at two institutions between June 2019 and March 2021. Eligible colorectal polyps (≤10 mm) were randomly assigned in a 1:1 ratio to receive either CSP with a conventional snare made of normal-diameter wire (0.40 mm) or CSP with a dedicated snare made of thin wire (0.23 mm). The primary endpoint was the complete resection rate determined on histological assessment of the resected specimen.

RESULTS

In total, 254 lesions in 152 patients were included, with 128 and 126 lesions assigned to the normal-diameter wire snare group and the thin-wire snare group, respectively. No significant differences were observed in patient characteristics between the two groups. The histological complete resection rate was significantly higher in the thin-wire snare group than in the normal-diameter wire snare group (70.0% vs 81.0%, P = 0.04). The normal-diameter wire snare group had significantly more cases of unclear horizontal margin evaluation than the thin-wire snare group (28.1% vs 15.9%, P = 0.02). No significant differences were observed between the two groups in the muscularis mucosa and submucosa of the resected specimens or the thickness of the submucosa in the resected specimens.

CONCLUSIONS

CSP with a dedicated thin-wire snare provides more specimens that can be evaluated at the horizontal end and increases the histological complete resection rate.

Outcomes of thin versus thick-wire snares for cold snare polypectomy: a systematic review and meta-analysis

BACKGROUND/AIMS

Cold snare polypectomy (CSP) is commonly used for the resection of colorectal polyps ≤10 mm. Data regarding the influence of snare type on CSP effectiveness are conflicting. Hence, this meta-analysis aimed to compare the outcomes and safety of thin- and thick-wire snares for CSP.

METHODS

A comprehensive search of the literature published between 2000 and 2021 was performed of various databases for comparative studies evaluating the outcomes of thin- versus thick-wire snares for CSP.

RESULTS

Five studies with data on 1,425 polyps were included in the analysis. The thick-wire snare was comparable to the thin-wire snare with respect to complete histological resection (risk ratio [RR], 1.03; 95% confidence interval [CI], 0.97-1.09), overall bleeding (RR, 0.98; 95% CI, 0.40-2.40), polyp retrieval (RR, 1.01; 95% CI, 0.97-1.04), and involvement of submucosa in the resection specimen (RR, 1.28; 95% CI, 0.72-2.28). There was no publication bias and a small study effect, and the relative effects remained the same in the sensitivity analysis.

CONCLUSION

CSP using a thin-wire snare has no additional benefit over thick-wire snares in small colorectal polyps. Factors other than snare design may play a role in improving CSP outcomes.

Safety of cold snare polypectomy with periprocedural antithrombotic agents for colorectal polyps: a systematic review and meta-analysis

BACKGROUND

We aimed to study the safety of cold snare polypectomy (CSP) for colorectal polyps in patients administered periprocedural antithrombotic agents.

METHODS

We searched the PubMed, Embase, and Cochrane Library databases through June 2021. The primary outcomes were the rates of delayed and immediate bleeding (requiring endoscopic hemostasis). Secondary outcomes included thromboembolic events. Meta-analysis using odds ratios (ORs) and corresponding 95% confidence intervals (CIs) was performed to compare the outcomes.

RESULTS

Seventeen studies, including five randomized trials, were included. Over 96% of polyps were ⩽1 cm. The pooled rates of delayed and immediate bleeding for patients receiving CSP and periprocedural antithrombotic agents were 1.6% and 10.5%, respectively. Both the delayed (OR = 4.02, 95% CI = 1.98-8.17) and immediate bleeding (OR = 5.85, 95% CI = 3.84-8.89) rates were significantly higher in patients using periprocedural antithrombotic agents than in non-users. Although both antiplatelet agents and anticoagulants increased the risk of delayed bleeding, the risks associated with the use of direct oral anticoagulants (DOACs; 2.5%) or multiple agents (3.9%) were particularly high. Compared to their counterparts, diminutive polyps and uncomplicated lesions not requiring hemoclipping were associated with lower risks of delayed bleeding (pooled estimates of 0.4% and 0.18%, respectively). Thromboembolic risk was similar among patients using and not using periprocedural antithrombotic agents.

CONCLUSIONS

CSP with periprocedural antiplatelet agents and warfarin may be feasible, especially for diminutive polyps. However, drug discontinuation should be considered with the use of DOACs or multiple agents which entail higher bleeding risk even with hemoclipping.

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.

Cold versus hot polypectomy/endoscopic mucosal resection-A review of current evidence

Background

Colonoscopy with polypectomy substantially reduces the risk of colorectal cancer (CRC) but interval cancers still account for 9% of all CRCs, some of which are due to incomplete resection.

Aim

The aim of this review is to compare the outcomes of cold and hot endoscopic resection and provide technical tips and tricks for optimizing cold snare polypectomy.

Results

Cold snare polypectomy (CSP) is the standard technique for small (≤10 mm) colorectal polyps. For large colonic polyps (>10 mm), hot resection techniques with use of electrocautery (polypectomy or endoscopic mucosal resection) were recommended until recently. However, the use of electrocoagulation brings serious adverse effects in up to 9% of the patients, such as delayed bleeding, post‐polypectomy syndrome and perforation. In recent years, efforts have been made to improve the polypectomy with cold snare in order to avoid these adverse effects of electrocoagulation without compromising the efficacy of the resection. Several authors have recently shown that the complication rates of CSP of polyps >10 mm is close to zero and recurrence rates varies between 5‐18%. Lower recurrence rates are found in serrated lesions (<8%).

Dedicated Cold Snare vs. Traditional Snare for Polypectomy of Diminutive and Small Lesions in a Porcine Model: A Research Group for Endoscopic Instruments and Stents (REIS) Study

BACKGROUND/AIMS

The aim of this in vivo animal study was to evaluate the effectiveness and safety of dedicated cold snare (DCS) compared with those of traditional snare (TS) for cold snare polypectomy (CSP).

METHODS

A total of 36 diminutive (5 mm) and 36 small (9 mm) pseudolesions were made by electrocoagulation in the colons of mini-pigs.

RESULTS

For the diminutive lesions, there were no significant differences in technical success rate, procedure time, or complete resection rate between the DCS and TS groups; the rate of uneven resection margin in the DCS group was significantly lower than that of the TS group. For small lesions, technical success rate and complete resection rate were significantly higher in the DCS group than in the TS group (100% [18/18] vs. 55.6% [10/18], p=0.003; 94.4% [17/18] vs. 40% [4/10], p=0.006). In addition, the procedure duration was significantly shorter, and the rate of uneven resection margin was significantly lower in the DCS group (28.5 sec vs. 66.0 sec, p=0.006; 11.1% [2/18] vs. 100% [10/10], p<0.001). Two cases of perforation occurred in the DCS group. Multivariate analysis revealed that DCS use was independently associated with complete resection.

CONCLUSION

DCS is superior to TS in terms of technical success, complete resection, and reducing the duration of the procedure for CSP of small polyps.

Rates of Incomplete Resection of 1- to 20-mm Colorectal Polyps: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Incomplete resection of neoplastic colorectal polyps can result in postcolonoscopy colorectal cancer. We performed a systematic review and meta-analysis to determine the incomplete resection rate (IRR) of colorectal polyps and associated factors.

METHODS

We searched MEDLINE, EMBASE, EBM Reviews, and CINAHL to identify full-text articles that reported IRRs of polyps 1 to 20 mm, published until March 2019. Exclusion criteria were studies of inflammatory bowel disease cohorts, referrals for difficult polypectomy, polyp sizes larger than 20 mm, and endoscopic submucosal resection and/or dissection as polypectomy approaches. IRRs were calculated based on findings from biopsies taken at polypectomy sites or assessments of margins of resected polyps. The primary outcome was IRR for snare removal of polyps 1 to 20 mm. Secondary outcomes included IRR for polyps 1 to 10 mm and 10 to 20 mm, IRR for hot and cold snare removal of polyps 1 to 10 mm and 10 to 20 mm, IRR of snare removal with or without submucosal injection, and IRR for forceps and cold snare removal of polyps 1 to 5 mm.

RESULTS

We identified 6148 reports and used 32 studies, with a total of 9282 polyps, in our quantitative analysis. The IRR for snare removal of polyps 1 to 20 mm was 13.8% (95% confidence interval [CI] 10.3-17.3; 13 studies, 5128 polypectomies). IRRs were 15.9% for snare removal of polyps 1 to 10 mm (95% CI 9.6-22.1; 9 studies, 2531 polypectomies) and 20.8% for snare removal of polyps 10 to 20 mm (95% CI 12.9-28.8; 6 studies, 412 polypectomies). The IRR for hot snare removal of polyps 1 to 10 mm was 14.2% (95% CI 5.2-23.2) vs 17.3% for cold snare polypectomy (95% CI 14.3‒20.3). The IRR for forceps removal of polyps 1 to 5 mm was 9.9% (95% CI 7.1-13.0) vs 4.4% for snare polypectomy (95% CI 2.9-6.1).

CONCLUSIONS

In a systematic review and meta-analysis, we found that colorectal polyps 1 to 20 mm are frequently incompletely resected, and that risk increases for polyps 10 mm or larger. There is no difference in IRRs of cold vs hot snares for polyps 1 to 10 mm. Snare polypectomy should be used over forceps for polyps 1 to 5 mm.

Clinical implications of decision making in colorectal polypectomy: an international survey of Western endoscopists suggests priorities for change

Introduction  Colonoscopy prevents colorectal cancer via the detection and resection of premalignant polyps. This effect may be attenuated by variations in polypectomy, with multiple techniques available and a wide range of experience amongst endoscopists. We assessed current practice against the best available contemporary evidence. Methods  An online survey was distributed to members of the gastroenterological and surgical societies of seven countries during July 2017. Images of colorectal polyps were presented and respondents requested to provide the polypectomy technique they would employ in their daily practice. Responses were compared to the evidence-based techniques in the 2017 ESGE Colorectal Polypectomy Guideline. Results  In total, 707 endoscopists (627 physicians, 71 surgeons, 9 nurse endoscopists, median practice duration 18 years) completed the survey. Of these, 3.1 % selected hot biopsy forceps and 5.2 % hot snare polypectomy (without submucosal lifting) to remove a 3 mm ascending colon polyp. Only 43.3 % selected cold snare polypectomy (CSP) to remove an 8 mm ascending colon polyp. Surgical referral was selected by 16.7 % of respondents for a 45 mm transverse colon polyp without endoscopic evidence of submucosal invasive cancer (SMIC). Endoscopic resection was selected by 12.0 % for an 80 mm sigmoid polyp with imaging consistent with deep SMIC, and a further 26.4 % selected tertiary endoscopist referral, suggesting they had not appreciated that it was endoscopically unresectable. Conclusion  CSP is underutilized for small polyp resection despite its favorable safety and efficacy. Benign polyps are commonly referred for surgery and overt SMIC is underappreciated using endoscopic imaging. Addressing these issues may reduce diathermy-related adverse events, surgery, and unnecessary colonoscopic procedures for patients and reduce rates of post-colonoscopy colorectal cancer.

Underwater cold snare polypectomy for colorectal adenomas

BACKGROUND AND AIM

Cold snare polypectomy (CSP) is a safe treatment for colorectal adenomas. However, the R0 resection rate is not sufficiently high because of inadequate resection of muscularis mucosa. We hypothesized that CSP in an underwater environment could improve this procedure by helping to safely achieve resection containing the muscularis mucosa. We have named this procedure underwater cold snare polypectomy (UCSP). We aimed to investigate the efficacy and safety of UCSP for colorectal adenomas.

METHODS

Between May 2017 and April 2018, patients diagnosed with colorectal adenomas <9 mm underwent UCSP. After follow-up colonoscopy 3 weeks later, the patients post-UCSP scars were biopsied. Outcomes were compared with those of a historical control group who underwent conventional CSP in our previous study using propensity score-matching methods.

RESULTS

Overall, 224 lesions in 65 patients were prospectively resected by UCSP. Pathologically, 209 lesions were adenomas (4.5 ± 1.5 mm) including one intramucosal carcinoma. Only one pathological residual adenoma was identified, but there was no significant difference in the residual rate between the UCSP and CSP groups (both 1.0%). No complications were observed. R0 resection rate and rate of area containing the muscularis mucosa in the UCSP group were significantly higher than those in the CSP group (80.2% vs 32.7%, P < 0.001; 50.0% vs 35.3%, P = 0.015).

CONCLUSION

Underwater cold snare polypectomy for diminutive and small colorectal adenomas was safe and effective from the perspective of pathological complete resection, which is likely facilitated by achieving an adequate depth of resection.

Comparison of Outcomes of Colorectal Polypectomy Using Traditional Snare and Rotary Snare: A Prospective Randomized Controlled Trial

Background and Objective

The aim of the current study was to compare the efficacy and safety of polypectomy by using rotary snare vs. traditional snare during colonoscopy.

Methods

A single-center randomized controlled trial, which included consecutive participants who were ≥18 years old and detected with polyp(s) during routine colonoscopy between July and September 2018, was conducted. Participants with colorectal polyps were randomized to receive polypectomy using rotary snares or traditional snares. The primary outcome measure was the comparison of the average time of removing a polyp between those two groups. The secondary outcome measure was to compare the polyp resection time by using SMSA (size, morphology, site, and access) scores.

Results

A total of two hundred participants were included in this study. Of them, 100 participants were randomly assigned to the rotary snare group (214 polyps) and the other 100 participants were randomly assigned to the traditional group (232 polyps). The mean resection time was significantly shorter in the rotary snare group than in the traditional snare group (24.41 ± 18.14 seconds vs. 29.53 ± 25.74 seconds, P = 0.021). In the subgroup analysis, the resection time was also shorter in the rotary snare group than in the traditional snare group in SMSA level 1 (18.51 ± 8.26 seconds vs.23.84 ± 15.07 seconds, P = 0.013) and in SMSA level 2 (25.03 ± 15.32 seconds vs.29.15 ± 24.82 seconds, P = 0.009), respectively.

Conclusion

Colorectal polyps could be removed more efficient by using rotary snares than by using traditional snares in SMSA level 1 and SMSA level 2.

The Cold Revolution: How Far Can It Go?

Cold resection for small colonic polyps, and larger lesions, is being rapidly and widely adopted. Driven by an impressive safety and cost profile compared with conventional polypectomy, these advantages are offset by the limitations of smaller and shallower resection, and absent thermal effects that may permit persistence of residual neoplasia. To overcome this, optimal cold snare technique requires inclusion of a margin of normal mucosa and a piecemeal resection technique for larger polyps. This article examines the fundamentals of cold snare resection and evidence for its application, theorizes on limits to its application, and identifies areas for further research.

Risk factors for incomplete polyp resection after cold snare polypectomy

BACKGROUND

Incomplete polyp resection (IPR) is recognized as a risk factor for interval colorectal cancer (ICC), and is, therefore, an important issue in polypectomy. Cold snare polypectomy (CSP) is a procedure that does not involve electrocautery and has no burn effect. Therefore, there is the possibility that the risk of ICC associated with IPR is higher in cases undergoing CSP than in those undergoing hot polypectomy. However, little is known about the risk factors for IPR after CSP.

PURPOSE

Precise identification of the risk factors can lead to prevention of IPR after CSP. Therefore, we performed this observational study for accurate identification of the risk factors for IPR after CSP.

METHODS

Medical records of a total of 501 patients with 1177 colorectal polyps that were resected at Omori Red Cross Hospital between October 2017 and March 2018 were retrospectively reviewed. The lateral and deep margins of the resected polyps were evaluated to check for the resection completeness.

RESULTS

Among the 1177 polyp resections, 1163 were included in the final analysis. IPR was detected in 206 (17.7%) cases. Performance of the resection by a trainee (OR (95% CI) 1.87 (1.328-2.632); P < 0.001) was identified as an independent risk factor for IPR in patients undergoing CSP.

CONCLUSIONS

Performance of the polypectomy by a trainee was identified as a significant risk factor for IPR in patients undergoing CSP. Prospective, randomized studies are necessary in the future to develop effective methods for the prevention/control of IPR after CSP.

Cold snare polypectomy: Indications, devices, techniques, outcomes and future

Colonoscopy has been shown to reduce the risk of colon cancer by enabling the removal of precancerous lesions. Although cold snare and hot snare polypectomy have similar retrieval rates and complete resection rates, rates of delayed bleeding tend to be lower with cold snare polypectomy than with hot snare polypectomy, especially for patients taking antithrombotic agents. However, among cold snares there may be differences in terms of the completeness of polyp excision, as complete removal appears more likely with thin-wire dedicated cold snares compared to the traditional, thick-wire cold snares. Cold snare polypectomy may be especially well suited for use in patients taking antithrombotic agents, due to its minimal risk of delayed bleeding. Histological analyses suggest that cold snare polypectomy causes less damage to blood vessels in the submucosal layers, which results in a reduced incidence of hemorrhage compared to hot snare polypectomy. However, cold snare removal of small polyps may result in fragmentation of small specimens during collection and concerns as to whether the resection is complete. An endoscopy biomarker of effective cold snare polypectomy technique is needed to ensure complete removal of non-pedunculated colorectal polyps ≤10 mm. Future uses of cold snare polypectomy may include piecemeal removal of sessile serrated adenoma/polyp lesions >10 mm. Currently, cold snare polypectomy should be considered a primary method for colorectal polyps of less than 10 mm, especially those in the 4- to 10-mm range.

Complete polypectomy and early detection and management of residual disease to reduce the risk of interval colorectal cancers

Advances in colorectal polyp detection and resection methods aim to reduce interval cancer rates. Complete polypectomy is essential to reduce the risk of early recurrence and the development of interval cancers. To achieve this, polyps must first be correctly identified and then completely excised. This article reviews current adenoma detection methods in use and the management of residual disease.