Clip artifact after closure of large colorectal EMR sites: incidence and recognition

Optical assessment of scars after endoscopic mucosal resection of large colorectal polyps in a multicenter, community hospital setting: is routine biopsy still necessary?

BACKGROUND

 Piecemeal endoscopic mucosal resection (EMR) of large (≥ 20 mm) nonpedunculated colorectal polyps (LNPCPs) is succeeded by a 6-month surveillance endoscopy to evaluate the post-EMR scar for recurrence. Data from expert centers suggest that routine tattoo placement and scar biopsies can be omitted, but data from community hospitals are lacking.

METHODS

 The agreement between optical assessment and histological confirmation by routine biopsies was evaluated in a post-hoc analysis of the STAR-LNPCP study (NTR7477), containing prospective data on 6-month post-EMR scar assessments in 30 Dutch community hospitals (October 2019 to May 2022). A standardized protocol was followed for documentation of optical characteristics, imaging, and biopsy of the post-EMR scar. RESULTS : In 1277 post-EMR scar assessments, identification of the scar was achieved in 1215/1277 (95 %). Tattoo placement did not influence scar identification. Scar biopsy was performed in 1050/1215 cases (86 %). Recurrences were seen in 200/1050 cases (19 %). There was good agreement between optical assessment of recurrence and histological confirmation (Cohen's kappa 0.78 [95 %CI 0.73-0.83]). The negative and positive predictive values were 98 % (95 %CI 97 %-99 %) and 74 % (95 %CI 68 %-80 %), respectively. A higher false-positive rate was seen after prior use of clips (11 % vs. 5 %; P = 0.02). Dedicated endoscopists identified the scar more often (96 % vs. 88 %; P < 0.001), and showed a lower optical recurrence miss rate (1 % vs. 3 %; P = 0.11) compared with nondedicated endoscopists. CONCLUSION : Based on this multicenter community hospital study, routine tattoo placement and scar biopsies of the post-EMR scar can be omitted. Assessment of post-EMR scars by dedicated endoscopists is advised.

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

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

Frequency and nature of endoscopic and pathologic errors leading to referral for endoscopic resection to a tertiary center

Background and study aims  We anecdotally encounter cases where referring endoscopists made errors in endoscopic interpretation of a colorectal lesion, sometimes combined with pathology errors at the referring centers, resulting in referral to our center for endoscopic resection. In this paper, we describe the frequency and nature of endoscopic and pathology errors leading to consultation for endoscopic resection. Patients and methods  Review of 760 consecutive referrals to our center over a 26-month interval. Results  In total, 28 (3.7 %) of all referred patients had ≥ 1 lesion that did not require any resection after investigation. There were 12 cases (1.6 % of all referrals) involving errors by both the referring endoscopist and the pathologist at the referring center. Errors commonly involved the ileocecal valve, lipomas, and mucosal prolapse changes. There were 15 additional referrals (2.0 % of all referrals) where no neoplastic lesion was identified at our center and either no biopsy was taken at the referring center (n = 9 patients, 10 lesions), the patient was referred although biopsy showed no neoplasia (n = 6), or the referring doctor correctly interpreted the lesion (lipoma), but the outside pathologist incorrectly reported adenoma (n = 1). Conclusions  Endoscopists at tertiary centers should expect referrals to clarify the nature of colorectal lesions as neoplastic or non-neoplastic. Community endoscopists with equivocal endoscopic findings and unexpected or equivocal pathology results can consider pathology review at their center or at an expert center before referral for endoscopic or surgical resection.

Assessment of submucosal distortion and mass effect seen at follow-up after colorectal EMR with ORISE (with video)

BACKGROUND AND AIMS

ORISE (Boston Scientific, Marlborough, Mass, USA) is a viscous gel used for submucosal injection. We noted anecdotally that ORISE is associated with submucosal distortion of EMR scars at follow-up.

METHODS

We blindly reviewed photographs of 30 consecutive EMR scars at follow-up after resections using ORISE and 30 resections using other agents. Distortion was scored on a scale of 0 (no submucosal distortion) to 5 (overt submucosal distortion).

RESULTS

The median submucosal distortion score at follow-up in ORISE cases was 3 (range, 0-5) versus 0 (range, 0-2) with other fluids (P < .001, Mann-Whitney U test) by 1 reviewer and 3 (range, 0-5) versus 2 (range, 0-5), respectively, by a second reviewer (P = .018). The kappa value for agreement in the submucosal distortion scores between the 2 experts was .148 for all photographs and .214 for the ORISE cases (overall minimal agreement).

CONCLUSIONS

ORISE can cause submucosal distortion in the region of EMR scars when they are viewed at follow-up. Such distortions must not be mistaken for submucosal tumor growth.

Prophylactic Clipping to Prevent Delayed Bleeding and Perforation After Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

To help prevent delayed adverse events after endoscopic surgery, endoscopists often place clips at the site. This meta-analysis aimed to assess the efficacy and safety of prophylactic clipping in the prevention of delayed bleeding and perforation after endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR).

METHODS

Multiple databases were searched from the inception dates to April 2021. And we included all relevant studies. Pooled odds ratio comparing the prophylactic clipped group versus nonprophylactic clipped group were calculated using the random effects model.

RESULTS

Twenty-seven articles fulfilled the inclusion criteria, with a total size of 8693 participants. There was statistically significant difference in prophylactic clipping versus no prophylactic clipping for delayed bleeding and perforation found in all studies (odds ratio: 0.35, 95% confidence interval: 0.25-0.49, P <0.01; odds ratio: 0.42, 95% confidence interval: 0.21-0.83, P <0.05; respectively). Besides, statistically significant difference was also found in subgroup analyses based on patients with lesions larger than 20 mm. Prophylactic clipping was more protective for duodenal delayed adverse events than colorectum. The use of clip closure was more protective to ESD-related delayed adverse events than EMR.

CONCLUSIONS

Prophylactic clipping after ESD and EMR was beneficial in preventing delayed bleeding and perforation.

Outcomes of Deep Mural Injury After Endoscopic Resection: An International Cohort of 3717 Large Non-Pedunculated Colorectal Polyps

BACKGROUND & AIMS

Although perforation is the most feared adverse event associated with endoscopic mucosal resection (EMR), limited data exists concerning its management. Therefore, we sought to evaluate the short- and long-term outcomes of intra-procedural deep mural injury (DMI) in an international multi-center observational cohort of large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs).

METHODS

Consecutive patients who underwent EMR for a LNPCP ≥20 mm were evaluated. Significant DMI (S-DMI) was defined as Sydney DMI Classification type III (muscularis propria injury, target sign) or type IV/V (perforation without or with contamination, respectively). The primary outcome was successful S-DMI defect closure. Secondary outcomes included technical success (removal of all visible polypoid tissue during index EMR), surgical referral and recurrence at first surveillance colonscopy (SC1).

RESULTS

Between July 2008 to May 2020, 3717 LNPCPs underwent EMR. Median lesion size was 35mm (interquartile range (IQR) 25 to 45mm). Significant DMI was identified in 101 cases (2.7%), with successful defect closure in 98 (97.0%) using a median of 4 through-the-scope clips (TTSCs; IQR 3 to 6 TTSCs). Three (3.0%) patients underwent S-DMI-related urgent surgery. Technical success was achieved in 94 (93.1%) patients, with 46 (45.5%) admitted to hospital (median duration 1 day; IQR 1 to 2 days). Comparing LNPCPs with and without S-DMI, no differences in technical success (94 (93.1%) vs 3316 (91.7%); P = .62) or SC1 recurrence (12 (20.0%) vs 363 (13.6%); P = .15) were identified.

CONCLUSIONS

Significant DMI is readily managed endoscopically and does not appear to affect technical success or recurrence.

The risk factors for prolonged hemostatic clip retention after endoscopic submucosal dissection for gastric neoplasm

BACKGROUND

Endoscopic hemostatic clipping is a safe and efficient treatment used to manage bleeding or perforation during endoscopic submucosal dissection (ESD) for gastric neoplasm. However, the natural history of applied hemoclips during ESD has not been elucidated. As prolonged clip retention limits the use of magnetic resonance imaging and may impede the ulcer healing process, we investigated the factors associated with prolonged hemoclip retention during gastric ESD.

METHODS

We retrospectively reviewed 199 patients who underwent gastric ESD with hemoclip application from January 2006 to January 2019. The primary outcome was the prolonged hemoclip retention rate 3 months after ESD. We examined the records of subjects followed at 3, 6, and 12 months and then annually after ESD to monitor clip retention.

RESULTS

The prolonged hemoclip retention rate at 3 months was 27.1% (54/199). The risk of hemoclip retention was significantly lower at the antrum (19.6%, P = 0.03). Hemoclips at the angle tended to remain longer than other locations in the stomach (40.6%, P = 0.081) while there was no difference in the number of applied clips depending upon the location of the lesion. By Kaplan-Meier survival analysis, clips at the antrum detached significantly earlier than those at other locations (P = 0.011).

CONCLUSIONS

Most of the hemostatic clips attached during ESD were spontaneously removed by 3 months after gastric ESD. However, clips positioned at angle are suspected to have a high probability of prolonged retention. With this in mind, more attention is needed when using hemoclips on angle.

Clip placement to prevent delayed bleeding after colonic endoscopic mucosal resection (CLIPPER): study protocol for a randomized controlled trial

BACKGROUND

Endoscopic mucosal resection (EMR) for large colorectal polyps is in most cases the preferred treatment to prevent progression to colorectal carcinoma. The most common complication after EMR is delayed bleeding, occurring in 7% overall and in approximately 10% of polyps ≥ 2 cm in the proximal colon. Previous research has suggested that prophylactic clipping of the mucosal defect after EMR may reduce the incidence of delayed bleeding in polyps with a high bleeding risk.

METHODS

The CLIPPER trial is a multicenter, parallel-group, single blinded, randomized controlled superiority study. A total of 356 patients undergoing EMR for large (≥ 2 cm) non-pedunculated polyps in the proximal colon will be included and randomized to the clip group or the control group. Prophylactic clipping will be performed in the intervention group to close the resection defect after the EMR with a distance of < 1 cm between the clips. Primary outcome is delayed bleeding within 30 days after EMR. Secondary outcomes are recurrent or residual polyps and clip artifacts during surveillance colonoscopy after 6 months, as well as cost-effectiveness of prophylactic clipping and severity of delayed bleeding.

DISCUSSION

The CLIPPER trial is a pragmatic study performed in the Netherlands and is powered to determine the real-time efficacy and cost-effectiveness of prophylactic clipping after EMR of proximal colon polyps ≥ 2 cm in the Netherlands. This study will also generate new data on the achievability of complete closure and the effects of clip placement on scar surveillance after EMR, in order to further promote the debate on the role of prophylactic clipping in everyday clinical practice.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03309683 . Registered on 13 October 2017. Start recruitment: 05 March 2018. Planned completion of recruitment: 31 August 2021.

Closure of Defects and Management of Complications

Large and complex colon polyps are frequently referred to surgery for fear of perforation that may need emergency surgery. During the last 15 years, advances in clip and suturing devices allowed us to close perforations and avoid surgery. In addition, we have made substantial progress in our understanding of the lesions at risk for either immediate or delayed perforation. This article focuses on the colonoscopic closure of resection defects and perforations and the prevention and treatment of colon perforations after endoscopic resection.

Endoscopic scar assessment after colorectal endoscopic mucosal resection scars: when is biopsy necessary (EMR Scar Assessment Project for Endoscope (ESCAPE) trial)

OBJECTIVE

It is unclear whether endoscopic assessment of scars after colorectal endoscopic mucosal resection (EMR) has to include biopsies, even if endoscopy is negative. Vice versa, endoscopic diagnosis of recurrent adenoma may not require biopsy before endoscopic reinterventions. We prospectively analysed various endoscopic modalities in the diagnosis of recurrence following EMR.

DESIGN

We conducted a prospective study of patients undergoing colonoscopy after EMR of large (≥20 mm) colorectal neoplasia. Endoscopists predicted recurrence and confidence level with four imaging modes: high-definition white light (WL) and narrow-band imaging (NBI) with and without near focus (NF). Separately, 26 experienced endoscopists assessed offline images.

RESULTS

Two hundred and thirty patients with 255 EMR scars were included. The prevalence of recurrent adenoma was 24%. Diagnostic values were high for all modes (negative predictive value (NPV) ≥97%, positive predictive value (PPV) ≥81%, sensitivity ≥90%, specificity ≥93% and accuracy ≥93%). In high-confidence cases, NBI with NF had NPV of 100% (95% CI 98% to 100%) and sensitivity of 100% (95% CI 93% to 100%). Use of clips at initial EMR increased diagnostic inaccuracy (adjusted OR=1.68(95% CI 1.01 to 2.75)). In offline assessment, specificity was high for all imaging modes (mean: ≥93% (range: 55%-100%)), while sensitivity was significantly higher for NBI-NF (82%(72%-93%)%)) compared with WL (69%(38%-86%); p<0.001), WL-NF (68%(55%-83%); p<0.001) and NBI (71%(59%-90%); p<0.001).

CONCLUSION

Our study demonstrates very high sensitivity and accuracy for all four imaging modalities, especially NBI with NF, for diagnosis of recurrent neoplasia after EMR. Our data strongly suggest that in cases of high confidence negative optical diagnosis based on NBI-NF, no biopsy is needed to confirm absence of recurrence during colorectal EMR follow-up. A high confidence positive optical diagnosis can lead to immediate resection of any suspicious area. In all cases of low confidence, biopsy is still required.

TRIAL REGISTRATION NUMBER

NCT02668198.

Safety and efficacy of hot avulsion as an adjunct to EMR (with videos)

BACKGROUND AND AIMS

Excision of all visible neoplastic tissue is the goal of EMR of colorectal laterally spreading tumors. Flat and fibrotic tissue can resist snaring. Ablation of visible polyps is associated with high recurrence rates. Avulsion is a technique to continue resection when snaring fails.

METHODS

We retrospectively analyzed colonic EMRs of 564 consecutive referred polyps between 2015 and 2017. Hot avulsion was used when snaring was unsuccessful. Polyps treated with and without avulsion were compared.

RESULTS

Hot avulsion was used in 20.9% (n = 112) of all resected lesions. The recurrence rates on follow-up colonoscopy were 17.52% in the avulsion group versus 16.02% in the non-avulsion group (P = .76). Hot avulsion was associated with a trend toward higher rates of delayed hemorrhage (5.35% vs 2.58%; P = .15) and post-coagulation syndrome (1.8% vs 0.47%; P = .15), but polyps treated with any avulsion were larger than those in which no avulsion was used (P < .001). There were an insufficient number of adverse events to perform a multivariable analysis to test the effects of avulsion, size, and location on the risk of overall adverse events.

CONCLUSIONS

Unlike previous reports of using argon plasma coagulation to treat visible polyps during EMR, hot avulsion of visible/fibrotic neoplasia was associated with similar EMR efficacy compared with cases that did not require hot avulsion. The safety profile of hot avulsion appears acceptable.

Narrow band imaging and white light endoscopy in the characterization of a polypectomy scar: A single-blind observational study

AIM

To assess the incremental benefit of narrow band imaging (NBI) and white light endoscopy (WLE), randomizing the initial technique for the detection of residual neoplasia at the polypectomy scar after an endoscopic piecemeal mucosal resection (EPMR).

METHODS

We conducted an observational study in an academic center to assess the incremental benefit of NBI and WLE randomly applied 1:1 (NBI-WLE or WLE-NBI) in the follow-up of a post-EPMR scar by the same endoscopist.

RESULTS

A total of 112 EPMR scars were included. The median baseline polyp size was 20 mm (interquartile range: 14-30). At first review, NBI and WLE showed good sensitivity (85.0% vs 78.9%), specificity (77.1% vs 84.2%) and overall accuracy (80.0% vs 82.5%). NBI after WLE (WLE-NBI group) improved accuracy, but this difference was not statistically significant [area under the curve (AUC): 86.8% vs 81.6%, P = 0.15]. WLE after NBI (NBI-WLE group) did not improve accuracy (AUC: 81.4% vs 81.1%, P = 0.9). Overall, recurrence was found in 39/112 (34.8%) lesions.

CONCLUSION

Although no statistically significant differences were found between the two techniques at the first post-EPMR assessment, the use of NBI after WLE may improve residual neoplasia detection. Nevertheless, biopsy is still required in the first scar review.

Clip retention rates and rates of residual polyp at the base of retained clips on colorectal EMR sites

BACKGROUND AND AIMS

Prophylactic endoscopic clipping may be effective in preventing delayed post-polypectomy hemorrhage after EMR of large colorectal lesions. The rate of retention of hemoclips on EMR sites has not been fully described. The aim of this study was to evaluate the adherence rates of hemoclips placed after EMR of large colorectal lesions.

METHODS

This was a retrospective review of a prospectively maintained database of large colorectal polyps (≥20 mm) referred to Indiana University Hospital between June 2006 and August 2015. Sites were closed with a mean of 4 clips. Patients were followed up for 3 to 6 months after EMR with a second follow-up 1 year later. Biopsy specimens of EMR scars were examined at follow-up, including the tissue at the base of retained clips.

RESULTS

There were 479 EMR sites in 424 patients that had first follow-up at our center with high-quality photographs of the EMR sites taken immediately after clip placement and at follow-up. Of 1407 Boston Scientific Resolution clips placed, 59 (4.2%) were retained at follow-up. Of 532 Cook Instinct clips placed, 46 (8.6%) were retained at first follow-up (P = .0001). There was no difference in the follow-up interval for the 2 clips. No patient had residual polyp by biopsy at the base of a retained clip.

CONCLUSIONS

Clip retention at first follow-up at 3 to 6 months after EMR was twice as high for the Cook Instinct clip compared with Boston Resolution clip but retention rates were low for both clips. Residual polyp at the base of retained clips was not a significant clinical problem.

A standardized imaging protocol is accurate in detecting recurrence after EMR

BACKGROUND AND AIMS

EMR of large laterally spreading lesions (LSL) in the colon is a safe and effective alternative to surgery. Post-EMR scar assessment currently involves taking biopsy specimens of the scar to detect residual or recurrent adenoma (RRA). The accuracy of endoscopic imaging of the post-EMR scar is unknown. We aimed to determine the accuracy of a standardized imaging protocol in post-EMR scar assessment.

METHODS

Prospective, single-center data from the Australian Colonic EMR study were analyzed. Consecutive patients undergoing first surveillance colonoscopy (SC1) after EMR of a large LSL were eligible. All scars were sequentially examined with high-definition white light (HD-WL) and narrow-band imaging (NBI) in a standardized fashion and then biopsies were performed. Endoscopic recurrence (recurrence at the post-EMR scar detected by systematic endoscopic assessment) was compared with the histologic findings.

RESULTS

One hundred eighty-three post-EMR scars were included. Thirty of 183 (16.4%) were confirmed to have RRA histologically at SC1. Thirty-seven of 183 (20.2%) post-EMR scars demonstrated RRA endoscopically. The sensitivity and specificity of endoscopic RRA detection were 93.3% (95% confidence interval [CI], 77.9%-99.2%) and 94.1% (95% CI, 89.1%-97.3%), respectively. The positive predictive value was 75.7% (95% CI, 58.8%-88.2%) and the negative predictive value was 98.6% (95% CI, 95.1%-99.8%). The diagnostic accuracy was 94.0%. Sensitivity was higher for the combination of HD-WL and NBI as opposed to HD-WL alone (93.3% vs 66.7%). The specificity was high for both HD-WL and HD-WL + NBI (96.1% and 94.1%, respectively). Flat morphology of RRA was better seen with NBI (P = .002).

CONCLUSIONS

Endoscopic detection of RRA in the post-EMR scar is highly accurate using a standardized imaging protocol with HD-WL and NBI. This allows real-time, accurate detection of recurrence and its concurrent treatment, and raises the possibility that routine biopsy of the post-EMR scar may not be necessary.

Update on Difficult Polypectomy Techniques

Endoscopists often encounter colon polyps that are technically difficult to resect. These lesions traditionally were managed surgically, with significant potential morbidity and mortality. Recent advances in endoscopic techniques and instruments have allowed endoscopists to safely and effectively remove colorectal lesions with high technical and clinical success and potentially avoid invasive surgery. Endoscopic mucosal resection (EMR) has gained acceptance as the first-line therapy for large colorectal lesions. Endoscopic submucosal dissection (ESD) has been reported to be associated with higher rate of en bloc resection and less risk of short-time recurrence, but with an increased risk of adverse events. Therefore, the role of colorectal ESD should be restricted to lesions with high-risk morphologic features of submucosal invasion. In this article, we review the recent literature on the endoscopic management of difficult colorectal neoplasms.

The influence of clips on scars after EMR: clip artifact

BACKGROUND AND AIMS

Laterally spreading lesions ≥20 mm are conventionally removed by EMR. Endoscopic clips are increasingly used to mitigate the risk of delayed bleeding. Clips may alter the endoscopic appearance of the scar after EMR, interfering with the assessment of adenoma recurrence. We aimed to evaluate this.

METHODS

Prospective, single-center data from the Australian Colonic Endoscopic resection study (January 2011-May 2015) were analyzed. Patients undergoing EMR of laterally spreading lesions with endoscopic clips used at the EMR defect were eligible. Data included patient and lesion characteristics and procedural, clinical, and histologic outcomes.

RESULTS

Clips were used in 111 of 885 lesions (12.5%). A total of 62 of 111 clipped lesions had standardized, high-definition, white light, and narrow-band images of the scars after EMR at first surveillance colonoscopy, and the patients were enrolled. Analysis of the images showed 4 situations: a bland scar (N = 27), residual adenoma (N = 6), mucosal elevation with normal pit pattern (N = 14), or granulation tissue related to the presence of residual clips (N = 15). The latter 2 entities were termed post-EMR scar clip artifact (ESCA). Overall, 29 of 62 previously clipped EMR sites (46.8%) had ESCA at a median follow-up of 5.2 months. Twenty scars had residual clips, and 15 of 20 (75.0%) showed ESCA (P = .002). Lesions clipped for prophylaxis of bleeding were more likely to show ESCA than those clipped for deep mural injury or intraprocedural bleeding (65.5% vs 41.7%; P = .006). ESCA was associated with female sex (P = .010) and greater age (P = .011).

CONCLUSIONS

ESCA is characterized by a nodular elevation of the mucosa with a normal pit pattern and can occur with or without residual clips. Prophylactic clip closure and the presence of residual clips are associated with ESCA. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01368289.).