Clip closure to prevent adverse events after EMR of proximal large nonpedunculated colorectal polyps: meta-analysis of individual patient data from randomized controlled trials

Closure strength of endoscopic hand-suturing in ex vivo porcine gastric ESD defect models: an exploratory animal study

BACKGROUND

Endoscopic hand-suturing (EHS) has been used to close gastrointestinal defects following endoscopic submucosal resection (ESD), but its closure strength needs further evaluation. This exploratory animal study aimed to compare the closure strength of EHS and titanium clips in ex vivo porcine gastric ESD defect models.

METHODS

Fifteen porcine stomachs were used to create ESD defect models, each featuring a 2-3-cm defect in the gastric body and another in the antrum. Defects were randomly assigned to three groups: EHS group (Group A), dense clipping group (Group B), and loose clipping group (Group C). Under endoscopy, Group A defects were sutured with 4 stitches, Group B with 7 clips, and Group C with 4 clips. The primary outcome measures were overall closure strength and closure strength per unit length, measured with a digital spring scale. Differences among groups were analyzed with the Kruskal-Wallis H test.

RESULT

All 30 defects were successfully closed endoscopically. Group A achieved significantly higher overall closure strength [1.06 kg (0.96 kg, 1.22 kg)] compared to Group B [0.27 kg (0.19 kg, 0.31 kg), P = 0.026] and Group C [0.11 kg (0.09 kg, 0.15 kg), P < 0.001]. For the closure strength per unit length, Group A [0.33 kg (0.27 kg, 0.35 kg)] also outperformed Group B [0.08 kg (0.06 kg, 0.10 kg), P = 0.023] and Group C [0.04 kg (0.03 kg, 0.04 kg), P < 0.001].

CONCLUSION

EHS can provide superior closure strength for ex vivo gastric ESD defects compared to simple titanium clips.

Post-polypectomy colorectal bleeding: current strategies and the way forward

Post-endoscopic mucosal resection (EMR) bleeding, or clinically significant post-EMR bleeding, is influenced by factors such as polyp size, right-sided colonic lesions, laterally spreading tumors, anticoagulant use, and comorbidities like cardiovascular or chronic renal disease. The optimal prophylactic therapy for post-EMR bleeding remains unknown, with no consensus on specific criteria for its application. Moreover, prophylactic measures, including clipping, suturing, and coagulation, have produced mixed results. Selective clipping in high-risk patients is cost-effective, whereas universal clipping is not. Studies and meta-analyses indicate that routine prophylactic clipping does not generally reduce post-polypectomy bleeding but may be beneficial in cases of large proximal lesions. Some studies have revealed that the post-polypectomy bleeding risk after EMR of transverse colonic lesions is lower than that of the ascending colon and caecum, suggesting limited efficacy of clipping in the transverse colon. Cost-effectiveness studies support selective clipping in high-risk groups, and newer static agents such as PuraStat are alternatives; however, their cost-effectiveness is undetermined. Further research is required to establish clear guidelines and refine prophylactic strategies to prevent post-EMR bleeding.

Tranexamic acid to prevent bleeding after endoscopic resection of large colorectal polyps: a pilot project

Background and aims

Delayed post-polypectomy bleeding (DPPB) can occur up to a month following the procedure but is typically seen within the first week. Tranexamic acid (TXA) is a member of a class of drugs called antifibrinolytic agents. It reduces fibrinolysis by slowing down the conversion of plasminogen to plasmin, which may prevent bleeding. The goal of this pilot study is to assess the feasibility of using tranexamic acid after endoscopic mucosal resection (EMR) of large (≥2 cm) non-pedunculated colorectal polyps (LNPCPs) to prevent DPPB.

Methods

This was a single centre feasibility study conducted at the Kingston Health Sciences Centre in 2021. After the polypectomy was completed, IV tranexamic acid was given [1 gram of TXA in 100 mL of normal saline] and infused over a 10-min interval. The participants received tranexamic acid 1 gram PO TID to be taken for 5 days.

Results

A total of 25 patients were enrolled with a mean polyp size of 3 cm. Intraprocedural bleeding occurred in 7 patients (28%) and all of these were treated with soft coagulation. Two patients had clipping for suspected muscle injury. All 25 patients received IV TXA post-procedure. Sixteen patients (64%) took every dose of the prescribed pills. One patient presented with post-polypectomy bleeding. All patients completed the day 30 follow-up phone call. There were no major adverse events.

Conclusions

TXA to prevent delayed post-polypectomy bleeding (DPPB) was feasible to use with no major adverse events reported. A randomized controlled study will be needed to see if TXA can significantly reduce DPPB.

Long-term adenoma recurrence and development of colorectal cancer following endoscopic mucosal resection in large non-pedunculated colonic polyps ≥4 cm

OBJECTIVES

Data of long-term follow up for large non pedunculated colorectal polyps (LNPCPs) ≥4 cm removed with piecemeal wide field endoscopic mucosal resection (PWF-EMR) are limited. We primarily evaluated the recurrence rates and secondarily the rates of post colonoscopic polypectomy colorectal cancer (PCPCRC) on a long-term basis.

METHODS

We retrospectively reviewed a prospectively-stored electronic database of all patients who underwent PWF-EMR for LNPCPs at the Venizeleion General Hospital, between 2009 and 2020. Eligible patients were those with LNPCPs ≥4 cm, deemed completely removed by endoscopic means and followed-up for a minimum of 36 months with at least two surveillance colonoscopies, the first one (SC1) (4-6) months after the initial PWF-EMR procedure and the second one (SC2) after (12-18) months. In 2023, all cases were checked for PCPCRC development.

RESULTS

Residual/early recurrent tissue was detected in 44 (31 %) cases among the 142 (82 males, 60 females) assessed during SC1. Late recurrent tissue was detected in 9 (6.6 %) cases among the 137 surveyed during SC2. Investigation did not reveal any case of PCPCRC .

CONCLUSIONS

This historical cohort shows that the PWF-EMR for LNPCPs ≥4 cm is a safe and definitive removal method while it is not associated with the appearance of PCPCRC.

Impact of margin thermal ablation after endoscopic mucosal resection of large (≥20 mm) non-pedunculated colonic polyps on long-term recurrence

BACKGROUND AND AIMS

The efficacy of colorectal endoscopic mucosal resection (EMR) is limited by recurrence and the necessity for conservative surveillance. Margin thermal ablation (MTA) after EMR has reduced the incidence of recurrence at the first surveillance colonoscopy at 6 months (SC1). Whether this effect is durable to second surveillance colonoscopy (SC2) is unknown. We evaluated long-term surveillance outcomes in a cohort of LNPCPs that have undergone MTA.

METHODS

LNPCPs undergoing EMR and MTA from four academic endoscopy centres were prospectively recruited. EMR scars were evaluated at SC1 and in the absence of recurrence, SC2 colonoscopy was conducted in a further 12 months. A historical control arm was generated from LNPCPs that underwent EMR without MTA. The primary outcome was recurrence at SC2 in all LNPCPs with a recurrence-free scar at SC1.

RESULTS

1152 LNPCPs underwent EMR with complete MTA over 90 months until October 2022. 854 LNPCPs underwent SC1 with 29/854 (3.4%) LNPCPs demonstrating recurrence. 472 LNPCPs free of recurrence at SC1 underwent SC2. 260 LNPCPs with complete SC2 follow-up formed the control arm from January 2012 to May 2016. Recurrence at SC2 was significantly less in the MTA arm versus controls (1/472 (0.2%) vs 9/260 (3.5%); p<0.001)).

CONCLUSION

LNPCPs that have undergone successful EMR with MTA and are free of recurrence at SC1 are unlikely to develop recurrence in subsequent surveillance out to 2 years. Provided the colon is cleared of synchronous neoplasia, the next surveillance can be potentially extended to 3-5 years. Such an approach would reduce costs and enhance patient compliance.

Association between prophylactic closure of mucosal defect and delayed adverse events after endoscopic resection: a systematic review and meta-analysis

OBJECTIVE

To investigate the potential of prophylactic closure of mucosal defects to prevent adverse events following endoscopic resection of superficial layers of the gastrointestinal (GI) wall.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

We searched PubMed, Embase, Web of Science and the Cochrane Library for studies eligible for inclusion in our meta-analysis from inception to February 2022.

DATA EXTRACTION AND SYNTHESIS

We compared the effects of closure versus non-closure of mucosal defects with respect to adverse events including delayed bleeding, delayed perforation and postpolypectomy coagulation syndrome (PPCS). We used a random-effects model for all analyses. Subgroup analyses were performed based on gastrointestinal sites, surgical procedures and study designs.

RESULTS

In total, this study includes 11 383 patients from 28 studies. For delayed bleeding, closure group was associated with a lower incidence (Risk Ratio [RR]: 0.40, 95% Confidence interval [CI]: 0.30 to 0.53, p<0.001; I2=25%) and consistent results were observed in the subgroups. Also, for delayed perforation, a combined analysis of all sites and surgical methods showed a protective effect of prophylactic closure of mucosal defects (RR: 0.42, 95% CI: 0.22 to 0.82, p=0.01; I2=0%). Similar results were observed in the subgroup analyses, despite the wide CIs. Regarding the PPCS, neither the pooled RRs nor the subgroup analyses showed significant differences.

CONCLUSION

Prophylactic closure of mucosal defects is beneficial in reducing the incidence of delayed bleeding and delayed perforation after endoscopic resection, but there is no significant difference in reducing the incidence of PPCS.

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.

The Use of Clips to Prevent Post-Polypectomy Bleeding: A Clinical Review

GOALS

The goal of this clinical review is to provide an overview of the current literature regarding the utility of prophylactic clips in reducing postpolypectomy bleeding and to provide an expert statement regarding their appropriateness in clinical practice.

BACKGROUND

Colonoscopy enables the identification and removal of premalignant and malignant lesions through polypectomy, yet complications including postpolypectomy bleeding (PPB) can arise. While various studies have explored applying clips prophylactically to prevent PPB, their effectiveness remains uncertain.

STUDY

A literature search conducted in PubMed and Embase identified 671 publications discussing clip use postpolypectomy; 67 were found to be relevant after screening, reporting outcomes related to PPB. Data related to clip utilization, polyp characteristics, and adverse events were extracted and discussed.

RESULTS

The current literature suggests that prophylactic clipping is most beneficial for nonpedunculated polyps ≥20 mm, especially those in the proximal colon. The utility of clipping smaller polyps and those in the distal colon remains less clear. Antithrombotic medication usage, particularly anticoagulants, has been linked to an increased risk of bleeding, prompting consideration for clip placement in this patient subgroup. While cost-effectiveness analyses may indicate potential savings, the decision to clip should be tailored to individual patient factors and polyp characteristics.

CONCLUSIONS

Current research suggests that the application of prophylactic clips can be particularly beneficial in preventing delayed bleeding after removal of large nonpedunculated polyps, especially for those in the proximal colon and in patients on antithrombotic medications. In addition, for large pedunculated polyps prophylactic clipping is most effective at controlling immediate bleeding.

Cold Versus Hot Snare Endoscopic Resection of Large Nonpedunculated Colorectal Polyps: Randomized Controlled German CHRONICLE Trial

BACKGROUND & AIMS

Endoscopic mucosal resection (EMR) is standard therapy for nonpedunculated colorectal polyps ≥20 mm. It has been suggested recently that polyp resection without current (cold resection) may be superior to the standard technique using cutting/coagulation current (hot resection) by reducing adverse events (AEs), but evidence from a randomized trial is missing.

METHODS

In this randomized controlled multicentric trial involving 19 centers, nonpedunculated colorectal polyps ≥20 mm were randomly assigned to cold or hot EMR. The primary outcome was major AE (eg, perforation or postendoscopic bleeding). Among secondary outcomes, major AE subcategories, postpolypectomy syndrome, and residual adenoma were most relevant.

RESULTS

Between 2021 and 2023, there were 396 polyps in 363 patients (48.2% were female) enrolled for the intention-to-treat analysis. Major AEs occurred in 1.0% of the cold group and in 7.9% of the hot group (P = .001; odds ratio [OR], 0.12; 95% CI, 0.03-0.54). Rates for perforation and postendoscopic bleeding were significantly lower in the cold group, with 0% vs 3.9% (P = .007) and 1.0% vs 4.4% (P = .040). Postpolypectomy syndrome occurred with similar frequency (3.1% vs 4.4%; P = .490). After cold resection, residual adenoma was found more frequently, with 23.7% vs 13.8% (P = .020; OR, 1.94; 95% CI, 1.12-3.38). In multivariable analysis, lesion diameter of ≥4 cm was an independent predictor both for major AEs (OR, 3.37) and residual adenoma (OR, 2.47) and high-grade dysplasia/cancer for residual adenoma (OR, 2.92).

CONCLUSIONS

Cold resection of large, nonpedunculated colorectal polyps appears to be considerably safer than hot EMR; however, at the cost of a higher residual adenoma rate. Further studies have to confirm to what extent polyp size and histology can determine an individualized approach. German Clinical Trials Registry (Deutsches Register Klinischer Studien), Number DRKS00025170.

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.

Large non-pedunculated colorectal polyp management: The elephant in the room

Minimally invasive innovations have transformed coloproctology. Specific to colorectal cancer (CRC), there has been a shift towards less invasive surgical techniques and use of endoscopic resection as an alternative for low risk T1 CRC. The role of endoscopic resection is however much more extensive: It is now considered the first line management strategy for most large (≥ 20 mm) non-pedunculated colorectal polyps, the majority of which are benign. This is due to the well-established efficacy, safety, and cost-effectiveness of endoscopic techniques compared to surgery. Multiple endoscopic modalities now exist with distinct risk-benefit profiles and their outcomes are further improved by site-specific technical modifications, auxiliary techniques, and adverse event mitigation strategies. Endoscopic capacity continues to evolve with emerging endoscopic techniques and expanding applications, particularly in the confines of a multi-disciplinary setting.

Systematic review of self-assembling peptides as topical agents for treatment and prevention of gastrointestinal bleeding

BACKGROUND/AIMS

Gastrointestinal bleeding is a significant and potentially lethal event. We aimed to review the efficiency and safety of self-assembling peptides for the treatment and prevention of gastrointestinal tract bleeding.

METHODS

We conducted a systematic search for studies describing the endoscopic use of self-assembling peptides for treatment or prevention of bleeding in the gastrointestinal tract in a parallel, independent fashion. The primary outcomes were rates of successful initial hemostasis, delayed bleeding, and rebleeding. The secondary outcomes were adverse events and ease and volume of gel used.

RESULTS

Seventeen studies were analyzed. Overall success rate of self-assembling peptides in gastrointestinal bleeding was 87.7% (38%-100%), regardless of etiology or associated treatments. Rebleeding rate ranged from 0% to 16.2%, with a mean of 4.7%, and overall delayed bleeding rate was 5% (range, 0%-15.9%). Only three adverse events were reported in a pooled number of 815 patients. The volume of gel used varied (0.43 to 3.7 mL) according to indication and type of bleeding.

CONCLUSIONS

The limited available data on the use of self-assembling peptides in gastrointestinal endoscopy suggest a high efficiency and good safety profile.

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.

Audit of hemostatic clip use after colorectal polyp resection in an academic endoscopy unit

Background and study aims Prophylactic closure of endoscopic resection defects reduces delayed hemorrhage after resection of non-pedunculated colorectal lesions ≥ 20 mm that are located proximal to the splenic flexure and removed by electrocautery. The risk of delayed hemorrhage after cold (without electrocautery) resection is much lower, and prophylactic clip closure after cold resection is generally unnecessary. The aim of this study was to audit clip use after colorectal polyp resection in routine outpatient colonoscopies at two outpatient centers within an academic medical center. Patients referred for resection of known lesions were excluded. Patients and methods Retrospective chart analysis was performed as part of a quality review of physician adherence to screening and post-polypectomy surveillance intervals. Results Among 3784 total lesions resected cold by 29 physicians, clips were placed after cold resection on 41.7% of 12 lesions ≥ 20 mm, 19.3% of 207 lesions 10 to 19 mm in size, and 2.8% of 3565 lesions 1 to 9 mm in size. Three physicians placed clips after cold resection of lesions 1 to 9 mm in 18.8%, 25.5%, and 45.0% of cases. These physicians accounted for 8.1% of 1- to 9-mm resections, but 69.7% of clips placed in this size range. Electrocautery was used for 3.1% of all resections. Clip placement overall after cold resection (3.9%) was much lower than after resection with electrocautery (71.1%), but 62.4% of all clips placed were after cold resection. Conclusions Audits of clip use in an endoscopy practice can reveal surprising findings, including high and variable rates of unnecessary use after cold resection. Audit can potentially reduce unnecessary costs, carbon emissions, and plastic waste.

Low delayed bleeding and high complete closure rate of mucosal defects with the novel through-the-scope dual-action tissue clip after endoscopic resection of large nonpedunculated colorectal lesions (with video)

BACKGROUND AND AIMS

Complete closure after endoscopic resection of large nonpedunculated colorectal lesions (LNPCLs) can reduce delayed bleeding but is challenging with conventional through-the-scope (TTS) clips alone. The novel dual-action tissue (DAT) clip has clip arms that open and close independently of each other, facilitating tissue approximation. We aimed to evaluate the rate of complete closure and delayed bleeding with the DAT clip after endoscopic resection of LNPCLs.

METHODS

This was a multicenter prospective cohort study of all patients who underwent defect closure with the DAT clip after EMR or endoscopic submucosal dissection (ESD) of LNPCLs ≥20 mm from July 2022 to May 2023. Delayed bleeding was defined as a bleeding event requiring hospitalization, blood transfusion, or any intervention within 30 days after the procedure. Complete closure was defined as apposition of mucosal defect margins without visible submucosal areas <3 mm along the closure line.

RESULTS

One hundred seven patients (median age, 64 years; 42.5% women) underwent EMR (n = 63) or ESD (n = 44) of LNPCLs (median size, 40 mm; 74.8% right-sided colon) followed by defect closure. Complete closure was achieved in 96.3% (n = 103) with a mean of 1.4 ± .6 DAT clips and 2.9 ± 1.8 TTS clips. Delayed bleeding occurred in 1 patient (.9%) without requiring additional interventions.

CONCLUSIONS

The use of the DAT clip in conjunction with TTS clips achieved high complete defect closure after endoscopic resection of large LNPCLs and was associated with a .9% delayed bleeding rate. Future comparative trials and formal cost-analyses are needed to validate these findings. (Clinical trial registration number: NCT05852457.).

Effectiveness of prophylactic clipping in preventing postpolypectomy bleeding in aspirin users: a propensity-score analysis

BACKGROUND AND AIMS

Antithrombotic use is a significant risk factor of postpolypectomy bleeding (PPB). Evidence of prophylactic clipping is only available for proximal and large colonic lesions in the general population. Dedicated studies to examine the benefit of prophylactic clipping in patients on aspirin remain scarce.

METHODS

A propensity score-weighted retrospective cohort study was performed in a tertiary referral center from January 2018 to September 2021. Patients who received aspirin and underwent colonoscopic polypectomy, EMR, or endoscopic submucosal dissection were included. Data on baseline demographics, medications, and endoscopic factors (polyp number, size, location, and morphology; resection method; and prophylactic clipping) were captured. Propensity score-weighted models were developed between prophylactic clipping and no clipping groups. The primary outcome was delayed PPB within 30 days, with a composite endpoint consisting of repeated colonoscopy for hemostasis, requirement of blood transfusion, or hemoglobin drop >2 g/dL.

RESULTS

A total of 1373 patients with 3952 polyps were included. Baseline characteristics were balanced between the 2 groups. In the multivariate analysis, the largest polyp size was a significant risk factor for PPB (odds ratio, 1.07; 95% confidence interval, 1.02-1.11; P = .002). Prophylactic clipping was not associated with a reduced risk of PPB (odds ratio, 1.34; 95% confidence interval, .83-2.18; P = .240) and did not show any risk reduction in subgroups with different polyp sizes and locations and endoscopic resection techniques.

CONCLUSIONS

Prophylactic clipping was not associated with a lower risk of PPB in aspirin users after endoscopic resection of colorectal polyps. Aspirin use should not be regarded as the only factor for the routine use of prophylactic clips.