Introduction

Endoscopic removal of large gastrointestinal polyps can be technically challenging. A novel rigidizing overtube (ROT) was developed as a platform to facilitate endoscopic removal of these polyps. The purpose of our study was to prospectively evaluate the clinical efficacy and safety of ROT in the management of GI polyps.

Aims & Methods

This was an observational, prospective, single-center study between May 2021 - March 2023 enrolling patients undergoing EMR (endoscopic mucosal resection) or ESD (endoscopic submucosal dissection) for large polyps. The primary outcome was device safety and technical success of ROT. Safety and performance data were collected intra-procedurally and at 1 month post. Secondary endpoints included clinical success, insertion times, total procedure time, and investigator feedback post-procedure. Technical success was defined as a successful placement of the overtube resulting in safe manipulation of the lesion/polyp. Clinical success was defined as the ability for the ROT to allow endoscopic removal of polyps without changing the initial resection intent.

Results

A total of 109 subjects were enrolled into the study comprising 114 total polyps. The most common polyp location was the ascending colon and cecum (Table). 28.95% and 71.05% of polyps were removed via EMR and ESD/Hybrid ESD, respectively (Table). Technical and clinical success was achieved 98.24% and 77.19% of the time, respectively. Total mean size of all polyps was 65.1mm +/- 57.7. There was a significant difference in total procedure time between EMR and ESD (69.6 minutes +/-41.5 vs 91.6 minutes +/- 38.9, p=0.0087). Dissection speed for polyps undergoing ESD was 9.3cm2/hr. Tissue traction during ESD was only needed in 45.6% of polyps most commonly via clip-band traction. En bloc and R0 resection rates for polyps removed via ESD were 90.1% (n=73) and 84% (n=68), respectively. On endoscopist feedback, the ROT was thought to assist in resection in 98.2% of polyps, although the polyp was in a somewhat/very difficult location 76.3% of the time. For polyps in difficult locations, the ROT was able to maintain scope position without falling back even once 64.9% of the time. There was no device related malfunctions that necessitated device removal. Mean time to reach the polyp was only 6.98min +/- 4.7. No device related adverse events occurred (Table 2).

Demographical data and polyp characteristics for patients undergoing endoscopic resection of GI polyps using the ROT (rigidizing overtube)

Conclusion

In this prospective study, the novel rigidizing overtube was safe and maintained a high technical/clinical success rate during the resection of GI polyps. Its ease of use, ability to provide stability, and conduit function allow for efficient endoscopic resection despite difficult polyp locations. Further randomized studies are needed to determine when its use should be implemented during endoscopic resection.

Disclosure

Mohamed O. Othman: Mohamed O Othman is a consultant for Olympus, Boston Scientific Corporation, Abbvie, ConMed, Neptune Medical and Apollo.
Salmaan A. Jawaid: Salmaan Jawaid is a consultant for ConMed and Boston Scientific Corporation.
Tara Keihanian: Tara Keihanian is a consultant for ConMed and Neptune Medical.

Introduction

Endoscopic resection of colonic tumors by endoscopic submucosal dissection (ESD) is now gaining worldwide acceptance. However, it is a technically challenging procedure with a delayed bleeding and perforation rate of 0.1-3.1% and 0.3-0.7% respectively.^{1, 2} Prophylactic closure of post endoscopic mucosal resection (EMR) defects in the right colon has been recommended to reduce adverse events.³But there is no consensus on post ESD closure. There have been many reports regarding prophylactic clip closure being beneficial to prevent delayed adverse events post colorectal ESD.^{4, 5} Though there is no data that exclusively evaluates colonic defects which may be more high risk than rectal defects due to thinner wall and intra- peritoneal location. Several endoscopic techniques are now available for closure of large mucosal defects.

Aims & Methods

This study aims to determine the impact of prophylactic closure on outcomes of colonic ESD and evaluate various closure methods. This is a retrospective, multicenter study which included consecutive patients undergoing ESD for resection of superficial colonic neoplasm from April-October, 2024. Rectal, ileo cecal valve, and appendiceal orifice lesions were excluded. Recurrent lesions, multiple lesions simultaneously treated, and lesions associated with inflammatory bowel disease were also excluded. Patients were allocated to closure and non closure groups which were compared using univariate analysis. Primary outcomes were delayed adverse events (bleeding and perforation), and duration of hospitalization. Sub group analysis was done to compare the closure methods used in this study.

Results

Total 271 patients were involved in this study where 190 patients (mean + SD age 63.5 ± 10.36 years, 92(48.4%) men) underwent post ESD closure and 81 patients (mean + SD age 65.4 ± 11.92 years, 32(40%) men) were in the non closure group. There were no significant differences in age, sex, location (Table), patients using anticoagulants (32(16.8%) vs 11(13.6%), P= 0.501), and patients having intraprocedural perforation/deep muscle injury in both groups (Table). The en bloc resection rate was 263/271 (97%) and R0 resection rate was 204/271 (75.3%). The mean specimen size of the closure group was significantly higher (Table). There was no significant difference in delayed adverse events (Table). The procedure time was higher in the closure group (median(IQR) 62(31.5-106.5) vs 37(25-57.75) minutes, P<0.001), but the duration of hospitalization was lesser (median(IQR) 1(0-5) vs 4(1-6) minutes, P<0.001). The closure methods used were endoclips only (n=125), clip with line pulley securing (CLiPS) technique ⁶ (n=54), X-tack (n=10), and overstitch (n=1). CLiPS technique was associated with shortest procedure time (median(IQR) 72(39.5-109) vs 38(24-57) vs 124.5(110.5-164.5) minutes, P<0.001). X-tack could close significantly larger defects (mean + SD 34.24 + 12.89 vs 40.47 + 14.78 vs 59.6 + 25.61 mm, P<0.001).

Conclusion

Prophylactic closure of post colonic ESD defects has no significant impact on delayed adverse events, but it reduces hospitalization time.

References

1. Fujishiro M, Yahagi N, Kakushima N, et al. Outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms in 200 consecutive cases. Clin Gastroenterol Hepatol. 2007;5(6):678 83.
2. Isomoto H, Nishiyama H, Yamaguchi N, et al. Clinicopathological factors associated with clinical outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms. Endoscopy. 2009;41(8):679–83.
3. Ferlitsch M, Hassan C, Bisschops R, et al. Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline–Update 2024. Endoscopy. 2024 Apr 26.
4. Omori J, Goto O, Habu T, et al. Prophylactic clip closure for mucosal defects is associated with reduced adverse events after colorectal endoscopic submucosal dissection: a propensity-score matching analysis. BMC gastroenterology. 2022 Mar 26;22(1):139.
5. Liu M, Zhang Y, Wang Y, et al. Effect of prophylactic closure on adverse events after colorectal endoscopic submucosal dissection: A meta‐analysis. Journal of Gastroenterology and Hepatology. 2020 Nov;35(11):1869-77.
6. Minato Y, Ohata K, Kimoto Y, et al. A modified approach for closing endoscopic submucosal dissection defects using clip with line pulley securing technique and endoloop. VideoGIE. 2024 Jul 1;9(7):320-3.
   

Introduction

Endoscopic mucosal resection (EMR) is the standard treatment for large (≥20 mm) non-pedunculated colonic polyps. However, outcomes vary depending on lesion complexity. The SMSA classification (Size, Morphology, Site, Access) identifies high-risk polyps that are technically challenging and more prone to adverse events and recurrence. Despite technical advances, outcome data for EMR in SMSA level 4 lesions remain limited.

Aims & Methods

To evaluate the clinical outcomes of EMR for highly complex colorectal polyps, with a focus on technical success, adverse events, and endoscopic recurrence.
This was a single-center, retrospective observational study conducted at a tertiary hospital between 2020 and 2024. Patients with polyps classified as SMSA level 4 (score >12) who underwent EMR were included. Technical success was defined as complete macroscopic resection. Intraprocedural events included significant bleeding requiring endoscopic intervention (managed with snare-tip soft coagulation) and deep mural injury (DMI), classified according to the Sydney system (type III/IV). Recurrence was defined as histologically confirmed neoplasia at the resection site, evaluated at 6 months (SC1) and 12 months (SC2). Clinically significant post-procedural bleeding (CSPEB) was defined as bleeding requiring prolonged hospitalization, blood transfusion, or additional procedures.

Results

A total of 158 lesions in 147 patients (mean age 69.6 ± 12.0 years; 45.6% women) classified as SMSA 4 were included. Fourteen endoscopists were involved in the procedures. Of the lesions, 44.9% of lesions were larger than 40 mm, 96.2% were sessile or flat, 77.2% were located in the right colon and 67.7% had difficult access. Additionally, 6.3% arose on a scar tissue and 13.9% on a difficult location (ileocecal valve, anal verge or appendix). Histological findings showed adenomas in 63.9%, serrated lesions in 22.8%, and adenocarcinomas in 12%. Technical success on the first attempt was achieved in 144/158 lesions (91.1%). Intraprocedural bleeding occurred in 16 of 158 lesions (10.1%), and deep mural injury in 1/158 lesions (0.6%). Clinically significant post-procedural bleeding occurred in 9/147 patients (6.1%), while several factors were associated with bleeding in univariate analysis (including age and Charlson score), only the use of anticoagulants and antiplatelet agents remained significant in multivariate analysis. No late perforations or deaths were reported.

Among the 120 lesions that underwent follow-up at SC1, 27 (22.5%) showed recurrence. Among the 79 lesions that underwent follow-up at SC2, 8 (10.1%) showed recurrence. All recurrences, except for one, were treated endoscopically. Multivariate analysis identified cold EMR (OR 5.63), intraprocedural bleeding (OR 5.52), and technical difficulty (OR 3.92) as independent risk factors for recurrence, while margin ablation was protective (OR 0.33). Finally, 4(2.5%) patients required surgery due to technical issues.

Conclusion

EMR is a safe and effective treatment modality for highly complex colorectal polyps (SMSA 4) when performed by experienced endoscopists. However, recurrence remains a clinical challenge influenced by specific procedural factors. Ongoing post-resection surveillance is essential to ensure optimal long-term outcomes.

Introduction

Endoscopic resection of the appendiceal orifice polyps extending into the appendiceal lumen is challenging given the inability to determine polyp’s lateral margins. Endoscopic full thickness resection (EFTR) is an alternative technique for managing these polyps, but it is limited in polyps larger than 2 cm, or polyps extending to the base of the cecum or inside the appendiceal lumen. In addition, EFTR may lead to appendicitis. In this case series, we describe a novel technique for the removal of complex appendiceal orifice polyps via transcecal endoscopic appendectomy (TEA).

Aims & Methods

This case series includes patients who underwent TEA performed by a single endoscopist in the US for polyps larger than 2 cm that extended deeply into the appendiceal lumen or obstructed the appendiceal lumen. All cases were done under general anesthesia in endoscopy unit. The technique entailed performing a circumferential incision around the lateral margin of the polyp in the base of the cecum. Once the polyp was dissected by endoscopic submucosal dissection (ESD) technique from the base of the cecum, the incision was extended into the serosa of the cecal wall with continuous dissection of the appendix from the mesoappendix. Traction was then applied to pull the tip of the appendix intra-luminally within the cecum. The appendix was then dissected from the remining mesoappendix and cecal base. The defect was then closed using hemostatic clips. A 14-gauge catheter was routinely inserted above the umbilicus to prevent tension pneumo-peritoneum. Technical success was defined as achieving complete removal of the appendix and the polyp in an en bloc fashion.

Results

In total, five patients were included (60% female). The mean age of patients was 65.6 ± 7.5 years old. The average polyp size was 3.08 ± 0.6 cm. Technical success was achieved in 100% of the patients. The average procedure length was 98.6 ± 36.22 minutes. Completed closure of the defect was made via clips in all cases (average 5.8 ± 1.7 clips). The en bloc resection rate, R0 resection rate and curative resection rates were 100%. Patients were observed post procedurally for an average of 3 ± 1.3 days (range 1-5 days). Post-procedural mild abdominal discomfort (n=4) and leukocytosis (n=3) were managed conservatively with empiric antibiotics. One patient developed loculated fluid collection nine days post-procedure without development of any clinical symptoms. After treatment with empiric antibiotics, complete resolution of all collection was noted on follow-up outpatient imaging on day 17.

Table 1- Patient, polyp and procedure characteristics, outcome and follow up information

Conclusion

This is the first reported experience of transcecal endoscopic appendectomy for management of complex appendiceal orifice polyps in the West. This novel technique is safe and is associated with minimal risk profile in expert hands. Further prospective studies are needed to standardize the technique.

Disclosure

Mohamed O. Othman: Mohamed O Othman is a consultant for Olympus, Boston Scientific Corporation, Abbvie, ConMed, Creo Medical, Lumendi and Apollo. Mohamed O Othman received research grants from Lucid Diagnostics, AbbVie and ConMed.
Tara Keihanian: Tara Keihanian is a consultant for Lumendi, Neptune Medical and ConMed.

Clinical Case Summary

The endoscopic removal of polyps located at the appendiceal orifice is a challenge, particularly when extending inside the appendiceal lumen, due to its anatomic difficulty and risk of complications.
The endoscopic full-thickness resection (FTR) technique has become an non-surgical option for these lesions but with a non negligible risk of appendicitis.
With the present case we explore an alternative technique.
A 75-year-old man with iron deficiency anemia underwent upper digestive endoscopy and colonoscopy.
The upper digestive endoscopy was normal.
In the colonoscopy angiectasias were found in the cecum and multiple polyps in the left colon (the largest measuring 30 mm). The inspection of the appendix revealed an intra-appendiceal orifice lesion (Image A).
Only after inversion of the appendix it was possible to accurately assess the lesion: an approximately 15 mm sessile polyp (Images B, C).
We applied argon plasma for ectasias ablation and removed the left colon polyps by endoscopic mucosal resection.
Intra-appendiceal orifice polyp resection was performed underwater with a diathermic loop (Image D), with no immediate or late complications.
Histology revealed a sessile serrated adenoma with low-grade dysplasia.
The described technique, being a simpler, faster and cheaper option than the endoscopic-FTR is a valid and a cost effective one.

Introduction

Endoscopic resection (ER) of large non-pedunculated colorectal polyps (LNPCP) has advanced significantly, pushing boundaries to treat lesions of any size. However, a dearth of published data exists on the extremes of ER practice, particularly for large lesions creating circumferential or near-circumferential mucosal defects. While Japanese studies, focusing on ESD-resected LNPCP, show conflicting outcomes, two prominent Western series lean towards EMR-resected lesions. The Western landscape is evolving, with a notable rise in ESD for LNPCP. Our study delivers fresh insights, presenting outcomes from ER with ≥75% circumferential mucosal defects in a leading Western centre that predominantly favours ESD for such lesions. This signifies a transformative trend in ER methodology, underlining the efficacy of ESD in addressing intricate colorectal lesions, thereby shaping evolving standards.

Aims & Methods

1477 ERs of LNPCP ≥20mm were performed and grouped according to the extent of the mucosal defect and comparisons made between those with <75% and ≥75% defects. Independent predictors of stenosis were identified.

Results

137 patients had ER leaving ≥75% circumference defect, most located at or distal to the rectosigmoid, with ≥90% defects in 29 and 100% in 14. 31 (22.6%) were resected using EMR and 106 (77.3%) using ESD. En bloc resection was achieved in 64%, increasing to 88% in the last 4 years of the study where ESD was increasingly employed routinely. Overall complications were more likely in these patients (11.7% versus 3.4%, p<0.001), although there was no difference in the incidence of clinically significant perforation (p=0.41) or post-procedure bleeding (p=0.45). 101 patients had undergone surveillance. Stenosis developed in only 2 of 71 (2.8%) patients with defects ≥75% circumference but 10 of 18 (55.6%) patients with defects ≥90% and 10 of 12 patients (83.3%) with 100% circumferential defects. ≥90% circumference defect was an independent risk factor for stenosis (p<0.001). All patients with stenosis were managed successfully with either expectant management if asymptomatic or balloon dilatation. None have required surgical intervention for stenosis. Recurrence was more likely in those with ≥75% defect (OR 7.9, 95% CI 3.8-16.4, p<0.001) but was acceptable at an incidence of 15% at SC1

Conclusion

This is the largest western series to date reporting on outcomes of ER of LNPCP leaving near or fully circumferential defects, and the first to include significant numbers of ER performed by ESD. ER of LNPCP resulting in defects ≥75% of the luminal circumference is challenging but highly effective in avoiding surgery when performed in an expert centre. En bloc resection can be achieved in most cases, reducing recurrence. The only independent predictor of stenosis is ≥90% circumference defect but some patients improve with expectant management therefore pre-emptive intervention may not be warranted.