HOT VERSUS COLD SNARE FOR COLORECTAL POLYPECTOMIES SIZED UP TO 10MM: A SYSTEMATIC REVIEW AND META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS

Alça quente versus alça fria para polipectomias colorretais de até 10 mm: uma revisão sistemática e meta-análise de ensaios clínicos randomizados

ABSTRACT

Background:

Colorectal cancer is the third most common cancer, and prevention relies on screening programs with resection complete resection of neoplastic lesions.

Objective:

We aimed to evaluate the best snare polypectomy technique for colorectal lesions up to 10 mm, focusing on complete resection rate, and adverse events.

Methods:

A comprehensive search using electronic databases was conducted to identify randomized controlled trials comparing hot versus cold snare resection for polyps sized up to 10 mm, and following PRISMA guidelines, a meta-analysis was performed. Outcomes included complete resection rate, en bloc resection rate, polypectomy, procedure times, immediate, delayed bleeding, and perforation.

Results:

Nineteen RCTs involving 8720 patients and 17588 polyps were included. Hot snare polypectomy showed a higher complete resection rate (RD, 0.02; 95%CI [+0.00,0.04]; P=0.03; I ²=63%), but also a higher rate of delayed bleeding (RD 0.00; 95%CI [0.00, 0.01]; P=0.01; I ²=0%), and severe delayed bleeding (RD 0.00; 95%CI [0.00, 0.00]; P=0.04; I ²=0%). Cold Snare was associated with shorter polypectomy time (MD -46.89 seconds; 95%CI [-62.99, -30.79]; P<0.00001; I ²=90%) and shorter total colonoscopy time (MD -7.17 minutes; 95%CI [-9.10, -5.25]; P<0.00001; I ²=41%). No significant differences were observed in en bloc resection rate or immediate bleeding.

Conclusion:

Hot snare polypectomy presents a slightly higher complete resection rate, but, as it is associated with a longer procedure time and a higher rate of delayed bleeding compared to Cold Snare, it cannot be recommended as the gold standard approach. Individual analysis and personal experience should be considered when selecting the best approach.

Keywords:
Cancer; colorectal; polyps; polypectomy; colonoscopy; colon

RESUMO

Contexto:

O câncer colorretal é o terceiro câncer mais comum na população, e a prevenção é principalmente baseada em programas de screening, com a ressecção completa de lesões neoplásicas. Múltiplas técnicas de ressecção estão disponíveis, mas ainda há controvérsias sobre a melhor abordagem, especialmente em relação à taxa de ressecção completa e à taxa de sangramento tardio.

Objetivo:

Nosso objetivo foi avaliar a melhor técnica de polipectomia com alça para lesões colorretais de até 10 mm.

Métodos:

Foi realizada uma busca abrangente em bancos de dados eletrônicos (MEDLINE e EMBASE) para identificar ensaios clínicos randomizados que comparassem a ressecção com alça quente versus alça fria para pólipos de até 10 mm, seguindo as diretrizes PRISMA. Os desfechos incluíram taxa de ressecção completa, taxa de ressecção em bloco, tempo de polipectomia, tempo total do procedimento, sangramento imediato, sangramento tardio e perfuração.

Resultados:

Dezenove ensaios clínicos randomizados foram incluídos, totalizando 8.720 pacientes e 17.588 pólipos. A polipectomia com alça quente foi associada a uma maior taxa de ressecção completa (RD, 0,02; IC95% [+0,00, 0,04]; P=0,03; I ²=63%), embora também tenha sido associada a uma taxa mais alta de sangramento tardio (RD 0,00; IC95% [0,00, 0,01]; P=0,01; I ²=0%) e de sangramento tardio grave (RD 0,00; IC95% [0,00, 0,00]; P=0,04; I ²=0%). A polipectomia com alça fria foi associada a um menor tempo de polipectomia (MD -46,89 segundos; IC95% [-62,99, -30,79]; P<0,00001 I ²=90%) e a um menor tempo total de colonoscopia (DM -7,17 minutos; IC95% [-9,10, -5,25]; P<0,00001 I ²=41%). Não houve diferença significativa na taxa de ressecção em bloco (RD, 0,00; IC95% [-0,01, 0,01]; P=0,20; I ²=30%) ou na taxa de sangramento imediato (RD -0,00; IC95% [-0,01, 0,00]; P=0,34; I ²=11%). Não foram relatados casos de perfuração em nenhum dos grupos.

Conclusão:

A polipectomia com alça quente apresenta uma taxa ligeiramente mais alta de ressecção completa, mas, como está associada a um tempo de procedimento mais longo e a uma taxa mais alta de sangramento tardio em comparação com a polipectomia com alça fria, não pode ser recomendada como a abordagem padrão. A análise individualizada e a experiência pessoal devem ser consideradas ao escolher a melhor abordagem.

Palavras-chave:
Câncer; Colorretal; pólipos; polipectomia; colonoscopia; cólon

INTRODUCTION

Colorectal cancer (CRC) is the third most common cancer, and the second most common cause of cancer death worldwide, excluding nonmelanoma skin cancer¹. Previous studies have shown that the adequate identification and resection of superficial neoplastic lesions can prevent CRC, which is the cornerstone of its prevention². According to the most recent guidelines from the U.S. Preventive Services Task Force, individuals should begin screening for colorectal cancer at the age of 45³.

Endoscopic polypectomy is a safe, minimally invasive procedure for removing colorectal polyps. Several endoscopic resection methods are currently available for the treatment of polyps including hot snare polypectomy (HSP), cold snare (CSP), endoscopic mucosal resection (EMR), cold endoscopic mucosal resection (C-EMR), but the best resection method is still under investigation⁴. HSP has traditionally been the procedure of choice for polypectomies, as thermal ablation may be associated with a higher complete resection rate, although recent studies demonstrated a higher rate of adverse events, such as perforation and delayed bleeding^5-7.

Recently, a ‘cold revolution’ has evolved, with CSP being recommended as the procedure of choice in current guidelines^4,8, as previous studies have shown comparable resection rates with a better safety profile, mainly because it induces less damage to the submucosal vessels, consequently reducing the risk of post-polypectomy bleeding, and is associated with a shorter procedure time^5,6,9. The use of EMR techniques, including C-EMR, which usually was indicated for larger polyps, also has been growing recently for smaller polyps, even the ones up to 10mm, with studies showing it can be associated with a higher complete resection rate^10,11, as the submucosal lift may help to define a clear margin and facilitate the snare resection.

In recent years, many randomized controlled trials addressing the best polypectomy technique have been published. So, we conducted a systematic review and meta-analysis of RCTs to investigate the best practice in this scenario. Our goal was to evaluate the best polypectomy method for colorectal lesions up to 10 mm, and if the use of electrical current achieves better outcomes, including complete resection rate, en bloc resection, immediate bleeding, delayed bleeding, and perforation.

METHODS

Protocol and registration

This study was performed in conformity with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines¹² and was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the file number CRD42022370494. The study was approved by the Hospital das Clinics Ethics Committee of the University of Sao Paulo.

Search and study selection

We searched electronic databases (MEDLINE and EMBASE) from inception to August 2023. Our search strategies were:

• MEDLINE / PubMed: (adenomatous OR adenoma OR adenomatosis OR polyps OR polyp) AND (colon OR colorectal OR colonic OR rectal OR rectum OR colorectum OR intestinal OR intestine) AND (surgery OR snare OR forceps OR resection OR surgical instruments OR polypectomy) AND random*;

• Embase: (adenomatous OR adenoma OR adenomatosis OR polyps OR polyp) AND (colon OR colorectal OR colonic OR rectal OR rectum OR colorectum OR intestinal OR intestine) AND (surgery OR snare OR forceps OR resection OR surgical instruments OR polypectomy) - only randomized controlled trials.

Data collection process

Two independent investigators (Cavassola PRP and Landim DL) searched titles and abstracts to access eligibility. Then, a full-text evaluation confirmed that the studies fulfilled all eligibility criteria. Any disagreements were resolved by consultation with a third reviewer.

Eligibility criteria

We included only randomized controlled trials (RCTs), that assessed patients with colorectal polyps sized up to 10 mm and underwent polypectomy comparing hot versus cold snare methods. Outcomes included complete resection rate, en bloc resection, immediate bleeding, delayed bleeding, severe delayed bleeding, perforation, total colonoscopy time, and polypectomy time.

In the studies that included polyps bigger than 10mm, we only used the data available of polyps ≤10 mm. We excluded studies that were not written in English and excluded from the bleeding analysis studies with exclusively anticoagulated patients^7,13.

Definitions

• Complete resection rate: complete histologic resection, using biopsy of margins or direct evaluation of margins on the specimen (R0);

• Immediate bleeding (intraprocedural bleeding that occurred immediately after the polypectomy and persisted for at least 30 seconds, or that required hemostatic treatment);

• Delayed bleeding (all bleeding cases reported after the patient left the endoscopy room to 30 days after the procedure);

• Severe delayed bleeding (bleeding that occurred after the patient left the endoscopy room, to 30 days after the procedure, requiring hospitalization or a repeat colonoscopy);

• Polypectomy time (time in which the polyp was visualized, and resected);

• Total procedure time (Time from the insertion of the endoscope to the end of the colonoscopy).

Data extraction

The data were extracted by two investigators (Cavassola PRP and Landim DL), with the following data being extracted: name and year of the study, number of patients, age, gender, type of polypectomy, number of polyps, size of polyps, morphology, histology, location, complete resection rate, adverse events, polyp retrieval rate, immediate bleeding, delayed bleeding, severe delayed bleeding, total colonoscopy time, and polypectomy time. When insufficient data were presented in the published articles, the corresponding authors were consulted via e-mail for further elucidation.

Risk of bias and quality of studies

The risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials (RoB2)¹⁴. We analyzed the risk of bias for all included studies. The quality of evidence was assessed using the grading of recommendations assessment, development, and evaluation (GRADE)¹⁵.

Data synthesis and statistical analysis

Statistical analyses were conducted using the RevMan software Version 5.4 (Cochrane, London, UK). We used a random effects model to balance the heterogeneity of the result for all forest plots. When there was high heterogeneity, we performed a sensitivity analysis using a funnel plot and by omitting one study at a time to assess the influence of each study on the overall effect size of the outcomes. If the sample became homogeneous (I ²<50%) after excluding possible outliers, the studies were permanently excluded and considered true outliers. Outcome measures are described as risk difference (RD), and mean difference (MD), with their corresponding 95% confidence intervals (CI).

RESULTS

Study selection

The initial search identified 3298 studies. After removing duplicates, 2705 articles were identified and screened through title and abstract evaluation. Among them, 40 were selected for full-text assessment. Subsequently, we excluded 21 studies that were not randomized or did not compare hot versus cold methods for polypectomies. Finally, 19 studies were selected for this meta-analysis (Figure 1).

FIGURE 1
Study selection flowchart.

Study characteristics

All 19 studies were RCTs. A total of 8720 patients accounted for 17588 polypectomies. All studies reported analysis or sub-analysis of polyps ≤10 mm. A summary of the characteristics of the included trials is shown in Table 1.

TABLE 1
Characteristics of included studies.

Author and year	Study design	Polypectomy method	Polyp size	Number of patients	Number of Polyps	Inclusion criteria	Complete resection assessment	Outcomes evaluated
Chang, 20235	Multicentric RCT	CSP X HSP	4-10 mm	4270	10040	All polyp morphologies	Negative margin of the resected specimen	Complete resection rate, en bloc resection, delayed bleeding, polypectomy time, total procedure time
Rex DK, 202224	Multicentric RCT	CSP X C-EMR x HSP x EMR	6-15mm	235	286	Nonpedunculated polyps	Negative margin biopsies	Complete resection rate
Koyanagi R, 202230	Unicentric RCT	CSP x HSP	6-10mm	49	61	Nonpedunculated polyps	Negative margin of the resected specimen	Complete Resection rate, immediate bleeding, delayed bleeding,
Pedersen IB, 202225	Multicentric RCT	CSP x HSP	4-9mm	425	601	Nonpedunculated polyps	Negative margin biopsies	Complete resection rate, en bloc resection, immediate bleeding, delayed bleeding
Fatima H, 202220	Multicentric RCT	CF x CSP x HSP	4-6mm	260	318	Adenomatous Polyps	Negative margin of the resected specimen	Immediate bleeding, delayed bleeding
Varytimiadis L, 202134	Unicentric RCT	CSP x HSP x APC	5-9mm	112	121	All polyps in left colon	Negative margin of the resected specimen	Complete resection rate, immediate bleeding
Ito T, 202135	Unicentric RCT	CSP x HSP	6-10mm	332	332	Nonpedunculated polyps	Negative margin of the resected specimen	En Bloc resection, immediate bleeding, delayed bleeding, polypectomy time, total procedure time
De Benito Sanz M, 202036	Multicentric RCT	CSP x HSP	5-9mm	488	791	All polyp morphologies	Negative margin biopsies	Complete resection rate, en bloc resection, immediate bleeding, delayed bleeding,
Li D, 202011	Unicentric RCT	CSP x C-EMR x EMR	6-20mm	404	763	Any polyp type, except hyperplastic and inflammatory	Negative margin biopsies	Complete resection rate
Takeuchi Y, 201913	Multicentric RCT	CSP (+CA) x HSP (+HB)	≤10 mm	168	611	Nonpedunculated polyps	NA	Polypectomy time
Aizawa M, 201916	Multicentric RCT	CSP X HSP	≤10mm	273	727	All polyp morphologies	NA	Delayed Bleeding
Zhang Q, 201821	Unicentric RCT	CSP x EMR	6-9mm	358	525	Nonpedunculated polyps	Negative margin biopsies	Complete resection rate, en bloc resection, immediate bleeding, delayed bleeding, polypectomy time
Suzuki S, 201819	Unicentric RCT	CSP x HSP	≤10 mm	52	52	Nonpedunculated polyps	Negative margin of the resected specimen	Complete resection rate, en bloc resection, immediate bleeding, delayed bleeding
Kawamura T, 201729	Multicentric RCT	CSP x HSP (+ EMR)	4-9 mm	538	687	Nonpedunculated polyps	Negative margin biopsies	Complete resection rate, en bloc resection, immediate bleeding, delayed bleeding, polypectomy time
Papastergiou V, 201737	Multicentric RCT	C-EMR x EMR.	6-10 mm	155	164	Nonpedunculated polyps	Negative margin biopsies	Complete resection rate, immediate bleeding, delayed bleeding
Horiuchi A, 20157	Unicentric RCT	CSP (+CA) x HSP(+ CA)	≤10 mm	70	159	Any polyp time, except hyperplastic	Negative margin of the resected specimen	Complete resection rate, total procedure time
Gomez V, 201438	Unicentric RCT	CSP x HSP x CFP	<6 mm	37	62	Adenomatous and hyperplasic polyps	Negative margin biopsies or C-EMR of the resection site	Complete resection rate, immediate bleeding, delayed bleeding
Paspatis G, 201139	Unicentric RCT	CSP x HSP	3-8 mm	414	1083	All polyp morphologies	Negative margin of the resected specimen	Delayed bleeding, total procedure time
Ichise Y, 201140	Unicentric RCT	CSP x HSP	≤8 mm	80	205	Any polyp type except hyperplastic in rectum or sigmoid	Negative margin of resected specimen	Complete resection rate, immediate bleeding, delayed bleeding, total procedure time

• RCT: randomized controlled trial; CSP: cold snare polypectomy; C-EMR: cold snare endoscopic mucosal resection; HSP: hot snare polypectomy; EMR: endoscopic mucosal resection; APC: argon plasma coagulation; CA: continuous anticoagulation; HB: heparin bridging; NA: Not available.

Risk of Bias and quality of studies

The overall risk of bias is shown in Figure 2. There were no high-risk studies identified through Rob2¹⁴. The quality of the included studies was assessed using GradePRO and was considered adequate (Figure 3).

FIGURE 2
Overall risk of bias analyzed through Rob2.

FIGURE 3
GradePRO quality assessment. CI: confidence interval; MD: mean difference. Explanations: a: High heterogeneity. b: Different management of delayed bleeding between studies. c: Low event rate. d: Different definitions of immediate bleeding between studies. Endoscopists are not blinded.

Meta-analysis

Complete resection rate

In total, 13689 polypectomies from 14 studies were analyzed. HSP presented a higher complete resection rate than CSP (RD, 0.02; 95%CI [+0.00,0.04]; P=0.03;I ²=63%) (Figure 4). We conducted a sensitivity analysis to investigate heterogeneity, however, it was not resolved by sensitivity analysis.

FIGURE 4
Complete resection rate.

En bloc resection rate

A total of 13034 polypectomies from seven studies were analyzed. En bloc resection rate was similar between groups (RD, 0.00; 95%CI [-0.01, 0.01]; P=0.20; I ²=30%) (Figure 5).

FIGURE 5
En bloc resection.

Immediate bleeding

A total of 3688 polypectomies from 12 studies were included in this analysis. The study from Aizawa¹⁶ was detected as an outlier in the funnel plot analysis and was excluded. Immediate bleeding was similar between groups. (RD -0.00; 95%CI [-0.01, 0.00]; P=0.34;I ²=11%) (Figure 6).

FIGURE 6
Immediate bleeding.

Delayed Bleeding

We conducted the bleeding analyses including all delayed bleeding cases and a group of severe delayed bleeding. Regarding all cases of delayed bleeding, there were significantly more bleeding cases in the HSP group (RD 0.00; 95%CI [0.00, 0.01]; P=0.01;I ²=0%.) (Figure 7.1). When evaluating the severe bleeding rate, hot snare was also associated with a higher bleeding rate (RD 0.00; 95%CI [0.00, 0.00]; P=0.04;I ²=0%.) (Figure 7.2 )

FIGURE 7.1
Delayed bleeding (per patient).

FIGURE 7.2
Severe delayed bleeding (per patient).

Perforation

In total, 15412 polypectomies from 17 studies were analyzed. No polypectomy-associated perforation was described in either group (RD 0.00; 95%CI [-0.00, 0.00]; P=1.00;I ²=0%)⁵.

Polypectomy time and total procedure time

When evaluating the polypectomy time, cold snare was associated with a shorter polypectomy time in seconds (MD -46.89; 95%CI [-62.99, -30.79]; P<0.00001I ²=90%) (Figure 8.1). We conducted a sensitivity analysis to investigate heterogeneity, however, it was not resolved by sensitivity analysis.

FIGURE 8.1
Polypectomy time.

In the evaluation of total procedure time, sensitivity analysis was performed, and the study from Chang⁵ was detected as an outlier and was excluded. Cold snare was associated with a shorter total procedure time in minutes (MD -7.17; 95%CI [-9.10, -5.25]; p<0.00001I ²=41%). (Figure 8.2).

FIGURE 8.2
Total procedure time.

Subgroup analysis

Complete resection rate, without submucosal injection

When excluding all EMR procedures, 12602 polypectomies from 11 studies were analyzed. There was no statistically significant difference between groups in complete resection rate (RD 0.00; 95%CI [-0.01, 0.01]; P=0.88;I ²=4%) (Figure 9).

FIGURE 9
Complete resection rate HSP x CSP.

Complete resection rate - Hot EMR vs CSP

A total of 1171 polypectomies from four studies were analyzed. There was no statistically significant difference between hot EMR and cold snare polypectomy regarding complete resection rate (RD 0.04; 95%CI [-0.02, 0.10]; P<0.0001;I ²=86%) (Figure 10). We conducted a sensitivity analysis to investigate heterogeneity, however, it was not resolved by sensitivity analysis.

FIGURE 10
Complete resection rate Hot EMR x CSP.

Complete resection rate - Hot EMR vs C-EMR

When evaluating Hot EMR vs. C-EMR, we analyzed 408 polypectomies from three studies. There was no statistically significant difference between Hot EMR and C-EMR in terms of complete resection rate (RD 0.02; 95%CI [-0.01, 0.05]; P=0.22;I ²=0%) (Figure 11).

FIGURE 11
Complete resection rate Hot EMR x C-EMR.

DISCUSSION

Endoscopic management of colorectal polyps is key to preventing colorectal cancer, and high-quality resection is mandatory. For polyps up to 3 mm, the use of forceps can achieve a similar complete resection rate compared to snare¹⁷. When bigger than 3 mm and up to 10 mm, the use of a snare is considered the gold standard in the latest guidelines^8,18. Many new randomized trials were published recently, with a large number of polyps being evaluated. Hence, considering the new evidence, we conducted this systematic review and meta-analysis to reevaluate this issue.

The main finding was that when comparing all hot snare versus cold snare methods, the first is associated with a higher complete resection rate but with no difference in the en bloc resection rate. One possible explanation for the superiority of electrical current is a higher resection depth, although it does not produce a wider resection margin¹⁹. This also could impact the recurrence rate, although not evaluated in this study.

The ideal method to evaluate the complete resection rate is hard to achieve, and different approa­ches have been used in the studies, using either a negative biopsy of margins or a negative specimen margin. These methods are probably not ideal, but the gold standard (colonoscopy with re-evaluation of the site of the resected polyp) is an outcome very hard to achieve, especially because of high dropout rates during follow-up²⁰. In our meta-analysis, we conducted a subgroup analysis, to evaluate if there was any difference between these two methods of assessment, but no difference was found.

Besides these limitations, when we compared all hot methods versus all cold snare methods, there were some differences in the technique used to perform the polyp resection, especially the use, or not, of submucosal injection. The EMR technique may increase the complete resection rate, as shown in Zhang et al.²¹, and in a recently published network meta-analysis¹⁰, which evaluated the different techniques of polypectomies and the complete resection rate. It showed that EMR is associated with a higher complete resection rate, when compared to other polypectomy methods, for polyps from 6 to 9 mm. In this meta-analysis, we conducted direct subgroup analyses with different methods of polypectomy, but none of the techniques, including EMR, had superiority regarding complete resection rate. Network meta-analyses, which use both direct and indirect evidence, are subject to a higher level of bias than direct comparative meta-analyses²².

The use of different types of snares may also be important in the complete resection rate outcome. Previous meta-analyses evidenced that the use of a dedicated cold snare can be associated with a higher complete resection rate than CSP^9,23, probably due to its thinner wire and its shield shape, which can provide a better cutting performance and a more precise polypectomy²³. Most studies included in our meta-analysis allowed traditional snares and the use of dedicated snares for CSP. Two studies used exclusively dedicated snares for all CSP^24,25, but none showed a statistically significant difference in the resection rate compared to HSP.

The use of electrocautery and its settings also could influence the adverse event rate. There are mainly two types of electrical current - Coagulation and Cut modes, and a third, which is a combination of both - the blended current. The coagulation mode induces a low increase in temperature within cells, with the dissipation of heat causing dehydration and shrinkage, while the cutting current causes a rapid increase in temperature, causing the cells to rupture^26,27. In the included studies, forced and blended coagulation modes were used. A recent RCT comparing forced coagulation vs blended coagulation evidenced similar outcomes in polyps ≥20 mm, such as serious adverse events, complete resection rate, and polyp recurrence²⁸. The higher rate of adverse events may be related to the electrical current effect, and, with the data available, is not possible to recommend a better setting to improve outcomes and reduce the risk of adverse events.

Regarding bleeding, we could analyze immediate, delayed bleeding, and severe delayed bleeding. The immediate bleeding rate was similar between groups, and all bleeding cases were successfully controlled through endoscopic therapy. One of the studies allowed prophylactic clipping in the EMR groupv²⁹ but without difference in the results of the study.

In the analysis of the delayed bleeding, we demonstrated that cold snare methods are associated with a lower rate of delayed bleeding as previously speculated and shown in a propensity score-matching study⁶. We could analyze delayed bleeding and severe delayed bleeding, both being statistically significant toward fewer bleeding episodes in the cold snare group. This is probably explained due to the lack of thermal injury, and a lower rate of submucosal vessel injury³⁰. In a study by Horiuchi et al.³¹, there was a higher rate of arterial injury in the submucosa layer with HSP vs CSP (39% vs 22%, P=.023), and that probably is responsible for a higher incidence of delayed bleeding in the hot snare group.

When evaluating perforation, no cases were described in either group, probably because of its low incidence in polypectomies up to 10 mm, using either hot or cold snare polypectomy. Cold snare perforation in small polyps is rare, being described in a few case reports^32,33.

The cold snare methods are also associated with a shorter procedure time, including total colonoscopy and polypectomy time. The probable explanation is due to the necessity of preparing the electrocautery device. It also may be more cost-effective as it is less time-consuming due to the absence of electrosurgical units and related equipment.

To the best of our knowledge, this is the largest meta-analysis, that used only RCTs to evaluate colorectal polypectomies sized up to 10 mm. Overall, the present study has several strengths. First, many recently published studies were included, with a high number of patients, thus leading to more credible cumulative effects according to different outcome measures compared to previous meta-analyses. Secondly, we could analyze the different resection methods, the complete resection rate, colonoscopy time, and their adverse events, especially the bleeding outcome, evidencing the benefit of cold snare polypectomy in reducing the delayed bleeding rate.

However, our study has some limitations. Different hot and cold snare methods could be used for our main outcome. Despite using all techniques sepa­rating only the use of hot or cold snare, when completing a subgroup analysis, none of the polypectomy methods showed superiority in the analysis of the complete resection rate. Second, the method of assessment of the complete resection rate was different between studies, which could impact directly on the results. Although different, we conducted an analysis that showed that both methods had similar resection rates. Third, the polypectomies were conducted by different endoscopists, some more experienced than others, which may explain some discrepancy in the complete resection rate or the adverse events rate between studies, as some of them might have more expertise in some of the techniques and that could influence the result of the study.

CONCLUSION

In summary, hot snare methods achieved a higher complete resection rate than cold methods. The use of EMR or any of the other methods still cannot be defined as the gold standard, as it has a similar resection rate in the present study. The use of cold snare has some benefits, being associated with a lower delayed bleeding rate and a shorter procedure time. This is the best evidence up to this date from direct comparative studies for polyps up to 10 mm, however, the management of each polyp needs to be individualized, and suited according to the clinical scenario, patient characteristics, and personal experience.

REFERENCES

• ¹
  Sung H, Ferlay J, Siegel RL, Laversanne M, Soerjomataram I, Jemal A, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71:209-49.
• ²
  Zauber AG, Winawer SJ, O’Brien MJ, Lansdorp-Vogelaar I, van Ballegooijen M, Hankey BF, et al. Colonoscopic polypectomy and long-term prevention of colorectal-cancer deaths. N Engl J Med. 2012;366:687-96.
• ³
  US Preventive Services Task Force, Davidson KW, Barry MJ, Mangione CM, Cabana M, Caughey AB, et al. Screening for Colorectal Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;325:1965-77.
• ⁴
  Kaltenbach T, Anderson JC, Burke CA, Dominitz JA, Gupta S, Lieberman D, et al. Endoscopic Removal of Colorectal Lesions: Recommendations by the US Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol. 2020;115:435-64.
• ⁵
  Chang LC, Chang CY, Chen CY, Tseng CH, Chen PJ, Shun CT, et al. Cold Versus Hot Snare Polypectomy for Small Colorectal Polyps. Ann Intern Med. 2023;176:311-9.
• ⁶
  Takamaru H, Saito Y, Hammoud GM, Mizuguchi Y, Cho H, Sekiguchi M, et al. Comparison of postpolypectomy bleeding events between cold snare polypectomy and hot snare polypectomy for small colorectal lesions: a large-scale propensity score-matched analysis. Gastrointest Endosc. 2022;95:982-989.e6.
• ⁷
  Horiuchi A, Nakayama Y, Kajiyama M, Tanaka N, Sano K, Graham DY. Removal of small colorectal polyps in anticoagulated patients: a prospective randomized comparison of cold snare and conventional polypectomy. Gastrointest Endosc. 2014;79:417-23.
• ⁸
  Ferlitsch M, Moss A, Hassan C, Bhandari P, Dumonceau JM, Paspatis G, et al. Colorectal polypectomy and endoscopic mucosal resection (EMR): European Society of Gastrointestinal Endoscopy (ESGE) Clinical Guideline. Endoscopy. 2017;49:270-97.
• ⁹
  Tranquillini CV, Bernardo WM, Brunaldi VO, Moura ET de, Marques SB, Moura EGH de. Best Polypectomy Technique for Small and Diminutive Colorectal Polyps: A Systematic Review and Meta-Analysis. Arq Gastroenterol. 2018;55:358-68.
• ¹⁰
  Tziatzios G, Papaefthymiou A, Facciorusso A, Papanikolaou IS, Antonelli G, Marco S, et al. Comparative efficacy and safety of resection techniques for treating 6 to 20mm, nonpedunculated colorectal polyps: A systematic review and network meta-analysis. Dig Liver Dis. Dig Liver Dis. 2023;55:856-64.
• ¹¹
  Li D, Wang W, Xie J, Liu G, Wang R, Jiang C, et al. Efficacy and safety of three different endoscopic methods in treatment of 6-20 mm colorectal polyps. Scand J Gastroenterol. 2020;55:362-70.
• ¹²
  Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021;71:372. doi: 10.1136/bmj.n71.
  » https://doi.org/10.1136/bmj.n71
• ¹³
  Takeuchi Y, Mabe K, Shimodate Y, Yoshii S, Yamada S, Iwatate M, et al. Continuous Anticoagulation and Cold Snare Polypectomy Versus Heparin Bridging and Hot Snare Polypectomy in Patients on Anticoagulants With Subcentimeter Polyps: A Randomized Controlled Trial. Ann Intern Med . 2019;171(4):229-37.
• ¹⁴
  Sterne JAC, Savović J, Page MJ, Elbers RG, Blencowe NS, Boutron I, et al. RoB 2: a revised tool for assessing risk of bias in randomised trials. BMJ. 2019;366:l4898.
• ¹⁵
  Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ. 2008;336:924-6.
• ¹⁶
  Aizawa M, Utano K, Tsunoda T, Ichii O, Kato T, Miyakura Y, et al. Delayed hemorrhage after cold and hot snare resection of colorectal polyps: a multicenter randomized trial (interim analysis). Endosc Int Open. 2019;7:E1123-9.
• ¹⁷
  Wei MT, Louie CY, Chen Y, Pan JY, Quan SY, Wong R, et al. Randomized Controlled Trial Investigating Cold Snare and Forceps Polypectomy Among Small POLYPs in Rates of Complete Resection: The TINYPOLYP Trial. Am J Gastroenterol. 2022;117:1305-10.
• ¹⁸
  Kaltenbach T, Anderson JC, Burke CA, Dominitz JA, Gupta S, Lieberman D, et al. Endoscopic Removal of Colorectal Lesions-Recommendations by the US Multi-Society Task Force on Colorectal Cancer. Gastroenterology. 2020;158:1095-129.
• ¹⁹
  Suzuki S, Gotoda T, Kusano C, Ikehara H, Sugita A, Yamauchi M, et al. Width and depth of resection for small colorectal polyps: hot versus cold snare polypectomy. Gastrointest Endosc. 2018;87:1095-103.
• ²⁰
  Fatima H, Rex DK, Imperiale T. A Pilot Randomized Trial of Polypectomy Techniques for 4 to 6 mm Colonic Polyps. J Clin Gastroenterol. 2022;56:426-32.
• ²¹
  Zhang Q, Gao P, Han B, Xu J, Shen Y. Polypectomy for complete endoscopic resection of small colorectal polyps. Gastrointest Endosc. 2018;87:733-40.
• ²²
  Chaimani A, Caldwell DM, Li T, Higgins JP, Salanti G. Undertaking network meta-analyses. In: Cochrane Handbook for Systematic Reviews of Interventions. Cochrane. 2019;285-320. Available from https://training.cochrane.org/handbook
  » https://training.cochrane.org/handbook
• ²³
  Jung YS, Park CH, Nam E, Eun CS, Park D Il, Han DS. Comparative efficacy of cold polypectomy techniques for diminutive colorectal polyps: a systematic review and network meta-analysis. Surg Endosc. 2018;32:1149-59.
• ²⁴
  Rex DK, Anderson JC, Pohl H, Lahr RE, Judd S, Antaki F, et al. Cold versus hot snare resection with or without submucosal injection of 6- to 15-mm colorectal polyps: a randomized controlled trial. Gastrointest Endosc . 2022;96:330-8.
• ²⁵
  Pedersen IB, Rawa-Golebiewska A, Calderwood AH, Brix LD, Grode LB, Botteri E, et al. Complete polyp resection with cold snare versus hot snare polypectomy for polyps of 4-9 mm: a randomized controlled trial. Endoscopy. 2022;54:961-9.
• ²⁶
  ASGE Technology Committee, Tokar JL, Barth BA, Banerjee S, Chauhan SS, Gottlieb KT, et al. Electrosurgical generators. Gastrointest Endosc . 2013;78:197-208.
• ²⁷
  Waye JD. Management of complications of colonoscopic polypectomy. Gastroenterologist. 1993;1:158-64.
• ²⁸
  Pohl H, Grimm IS, Moyer MT, Hasan MK, Pleskow D, Elmunzer BJ, et al. Effects of Blended (Yellow) vs Forced Coagulation (Blue) Currents on Adverse Events, Complete Resection, or Polyp Recurrence After Polypectomy in a Large Randomized Trial. Gastroenterology. 2020;159:119-128.e2.
• ²⁹
  Kawamura T, Takeuchi Y, Asai S, Yokota I, Akamine E, Kato M, et al. A comparison of the resection rate for cold and hot snare polypectomy for 4-9 mm colorectal polyps: a multicentre randomised controlled trial (CRESCENT study). Gut. 2018;67:1950-7.
• ³⁰
  Koyanagi R, Honda M, Kawamura H, Hamada K, Horikawa Y, Shiwa Y, et al. Clinical Benefit of Polypectomy With Cutting Current for Colorectal Polyps: A Randomized Controlled Trial. Anticancer Res. 2022;42:3613-9.
• ³¹
  Horiuchi A, Hosoi K, Kajiyama M, Tanaka N, Sano K, Graham DY. Prospective, randomized comparison of 2 methods of cold snare polypectomy for small colorectal polyps. Gastrointest Endosc . 2015;82:686-92.
• ³²
  Rodríguez Sánchez J, Sánchez Alonso M, Pellisé Urquiza M. The “bubble sign”: a novel way to detect a perforation after cold snare polypectomy. Endoscopy. 2019;51:796-7.
• ³³
  Young E, Ruszkiewicz A, Singh R. Gastrointestinal: A case of cold-snare polypectomy perforation: Avoiding this rare complication. J Gastroenterol Hepatol. 2022;37:607.
• ³⁴
  Varytimiadis L, Viazis N, Gkolfakis P, Tribonias G, Tziatzios G, Kyriakopoulos G, et al. Cold snare polypectomy vs. hot snare polypectomy vs. argon plasma coagulation for small (5-9mm) left-sided colorectal polyps: a prospective randomized trial. Eur J Gastroenterol Hepatol . 2021;33(1S Suppl 1):e909-15.
• ³⁵
  Ito T, Takahashi K, Tanabe H, Sato K, Goto M, Sato T, et al. Safety and efficacy of cold snare polypectomy for small colorectal polyps: A prospective randomized control trial and one-year follow-up study. Medicine. 2021 Jun 11;100(23):e26296.
• ³⁶
  de Benito Sanz M, Hernández L, Garcia Martinez MI, Diez-Redondo P, Joao Matias D, Gonzalez-Santiago JM, et al. Efficacy and safety of cold versus hot snare polypectomy for small (5-9 mm) colorectal polyps: a multicenter randomized controlled trial. Endoscopy. 2022;54:35-44.
• ³⁷
  Papastergiou V, Paraskeva KD, Fragaki M, Dimas I, Vardas E, Theodoropoulou A, et al. Cold versus hot endoscopic mucosal resection for nonpedunculated colorectal polyps sized 6-10 mm: a randomized trial. Endoscopy. 2018;50:403-11.
• ³⁸
  Gómez V, Badillo RJ, Crook JE, Krishna M, Diehl NN, Wallace MB. Diminutive colorectal polyp resection comparing hot and cold snare and cold biopsy forceps polypectomy. Results of a pilot randomized, single-center study (with videos). Endosc Int Open . 2015;3:E76-80.
• ³⁹
  Paspatis GA, Tribonias G, Konstantinidis K, Theodoropoulou A, Vardas E, Voudoukis E, et al. A prospective randomized comparison of cold vs hot snare polypectomy in the occurrence of postpolypectomy bleeding in small colonic polyps. Colorectal Dis. 2011;13:e345-8.
• ⁴⁰
  Ichise Y, Horiuchi A, Nakayama Y, Tanaka N. Prospective randomized comparison of cold snare polypectomy and conventional polypectomy for small colorectal polyps. Digestion. 2011;84:78-81.

• Disclosure of funding: no funding received
• Declaration of use of artificial intelligence: none

Publication Dates

• Publication in this collection
  15 Mar 2024
• Date of issue
  2024

History

• Received
  24 Oct 2023
• Accepted
  19 Dec 2023