Introduction

Cold snare polypectomy (CSP) and underwater endoscopic mucosal resection (UEMR) represent relatively novel techniques for the management of superficial non-ampullary duodenal epithelial tumors. While CSP has been demonstrated to be safe and efficacious in a large-scale clinical trial for non-ampullary duodenal adenomas (NADAs) with a diameter of less than 10 mm [1], UEMR has been shown to be safe and effective in a prospective clinical trial for NADAs with a diameter of less than 20 mm [2]. However, there is no consensus on which technique should be used for NADAs 10 mm or less.

Aims & Methods

This study aimed to evaluate the treatment outcomes of CSP and UEMR for NADAs 10 mm or less. Patients who underwent CSP or UEMR for NADAs 10 mm or less at our institution between January 2015 and December 2022 were included, excluding FAP and local recurrence cases. Adenomas were defined as either Vienna classification category 3 on preoperative biopsy or endoscopically diagnosed as adenomas. The decision to perform either CSP or UEMR, as well as mucosal closure at the ulcer base after resection, was left to the discretion of the endoscopist. Procedure time was measured from snare visibility on the monitor until the end of resection for CSP, and from the beginning of water immersion until the end of resection for UEMR. The resected specimens were pinned to the corkboard and submitted to the pathology department. Follow-up endoscopy was conducted 2–3 months after endoscopic treatment to confirm the presence or absence of residual lesions, followed by an annual endoscopic examination.

Results

A total of 51 lesions were treated using CSP, while 29 lesions were treated with UEMR. The location of the lesions was distributed as follows: 9.8%, 84.3%, and 5.9% for the first, second, and third regions in the CSP group; and 13.8%, 82.5%, and 6.3% in the UEMR group (p=0.84). The difference in lesion diameter between the CSP and UEMR groups was not statistically significant (6.3±2.5 mm and 7.3±2.2 mm, respectively; p=0.06). Preoperative biopsy was performed in 43.1% of the CSP group and 58.6% of the UEMR group (p=0.18). The mean procedure time for CSP and UEMR was 4.6±4.2 min and 6.1±6.9 min, respectively (p=0.29). Mucosal closure at the ulcer base was performed in 56.9% of the CSP group and 100% of the UEMR group (p<0.01). Neither group experienced intraoperative perforation, postoperative bleeding, or delayed perforation (95% CI: 0–7.0% for the CSP group, 0–11.9% for the UEMR group). The en-bloc resection rates were 96.8% for CSP and 100% for UEMR (p=0.17), and the electric current application rate for CSP was 7.8%. The final pathological diagnosis in the CSP group was 82.4% adenoma, 3.9% intramucosal adenocarcinoma, and 13.7% non-neoplasm, while in the UEMR group, it was 89.7% adenoma, 10.3% intramucosal adenocarcinoma, and 0% non-neoplasm (p=0.02). The lateral and vertical margin-negative rates were 62.8% and 94.1% in the CSP group, and 62.1% and 100% in the UEMR group, respectively (p=0.95 for lateral margin, p=0.19 for vertical margin). Local recurrence was detected in 3.9% of the CSP group and 0% of the UEMR group.

Conclusion

The rates of negative margins for both lateral and vertical margins were comparable between CSP and UEMR. Despite this, two recurrence cases were observed in the CSP group. UEMR was as safe as CSP, with no intraoperative or postoperative adverse events reported. Furthermore, given that the preoperative diagnosis of adenoma may include a certain number of adenocarcinomas, UEMR may be considered the preferred method for endoscopic resection of NADAs ≤10 mm in size.

References

[1] K. Takizawa, Y. Takeuchi, M. Ohmori, J. Fujisaki, S. Yoshimizu, T. Iwai, T. Yamada, T. Suzuki, M. Takeuchi, M. Yoshida, A. Miyakawa, H. Furuhashi, M. Matsuda, H. Araki, K. Ohno, T. Shimura, T. Ohta, K. Mori, H. Ishikawa, T. Gotoda, D-COP study Group. COLD SNARE POLYPECTOMY FOR SUPERFICIAL NON-AMPULLARY DUODENAL EPITHELIAL TUMOR: A MULTICENTER PROSPECTIVE CONFIRMATORY TRIAL (D-COP TRIAL). ueg journal. 2021 Oct suppl. 27-28.
[2] Yamasaki Y, Uedo N, Akamatsu T, Kagawa T, Higashi R, Dohi O, Furukawa M, Takahashi Y, Inoue T, Tanaka S, Takenaka R, Iguchi M, Kawamura T, Tsuzuki T, Yamasaki T, Yamashina T, Nasu J, Mannami T, Yamauchi A, Matsueda K, Aizawa S, Mitsuhashi T, Okada H; D-UEMR Study Group. Nonrecurrence Rate of Underwater EMR for ≤20-mm Nonampullary Duodenal Adenomas: A Multicenter Prospective Study (D-UEMR Study). Clin Gastroenterol Hepatol. 2022 May;20(5):1010-1018.e3.

Introduction

The most popular endoscopic therapy for SNADETs is endoscopic mucosal resection (EMR), however it is difficult due to major serious adverse events and poor curative outcomes that result in a high recurrence rate. Underwater endoscopic mucosal resection (UEMR) has recently attracted attention as a safe and effective method for superficial non-ampullary duodenal epithelial tumors (SNADETs). However, water is a fluid and it does not remain in all areas, and because it mixes easily with other substances, it sometimes becomes cloudy and reduces visibility. A new endoscopic gel product that does not mix with fluids and tends to remain in the injected area has recently been applied to EMR and is known as gel immersion EMR (GIEMR) or under-gel EMR. Unlike water, this gel product does not mix with intestinal fluids or blood, thus ensuring a good view of the gastrointestinal tract. Furthermore, it tends to stay in the injected area due to its viscoelasticity, which may shorten the treatment time.

Aims & Methods

In the present study, we compared the efficacy and safety of UEMR and GIEMR for treatment of SNADETs.
From February 2019 to January 2023, patients who underwent UEMR or GIEMR for SNADETs at the municipal hospitals were included in the study, and treatment outcomes were compared retrospectively in both groups. We identified 31 lesions of SNADETs with 3–18 mm in diameter who underwent UEMR or GIEMR. One lesion was excluded from the analysis because it was found to be in the stomach after surgery. The primary endpoint in this study was the difference in procedure time between the GIEMR and UEMR groups. The procedure time was defined as the time from the start of normal saline or gel injection into the lumen until the polyp was completely removed. En bloc resection rate, R0 resection rate and adverse events were evaluated as secondary endpoints.

Results

The 30 lesions in 29 patients were divided into the UEMR (n=12) and GIEMR (n=18) groups. There were no differences in age, gender, location, morphology and histological type between the UEMR and GIEMR groups, although the GIEMR group had a significantly larger median tumor diameter size (7 mm vs 11 mm, P=0.0006). GIEMR significantly reduced the procedure time compared with UEMR (5.5 min vs 10 min, P=0.016). There was no significant difference between the UEMR and GIEMR groups for en bloc resection rate (91% vs 94%, P=1.0) and R0 resection rate (58% vs 78%, P=0.42). No serious complications were observed in either group.

Conclusion

GIEMR was safe and had good therapeutic results for SNADETs and showed the potential to accelerate the procedure time compared with UEMR. This method may be particularly useful in areas where immersion in water is difficult. A multicenter study is needed to confirm the validity of our results.

Introduction

Japanese gastrointestinal stromal tumor (GIST) guidelines recommend that gastric submucosal tumors (SMT) < 2 cm should be followed up once or twice a year if asymptomatic and without malignant findings (ulceration, irregular border, and/or tumor growth), and SMT with malignant findings or a pathological diagnosis of GIST are relative indications for surgery¹. However, this management policy for SMT < 2 cm has not been fully evaluated.

Aims & Methods

This study aimed to clarify the long-term outcomes of patients with endoscopically diagnosed gastric SMT < 2 cm managed according to the guidelines. Patients with endoscopically diagnosed gastric gastrointestinal mesenchymal tumors (eGIMT) < 2 cm, including GIST, leiomyomas, and schwannomas, at our institution between September 2002 and December 2020 were included in this study. eGIMT was defined as an SMT with the same color as the surrounding mucosa, negative cushion sign, and mobility by biopsy forceps and/or a hypoechoic mass arising from the fourth layer of the gastric wall on endoscopic ultrasonography (EUS). The success rates of histological diagnosis by biopsy and EUS-guided fine needle aspiration biopsy (EUS–FNAB), rate of eGIMT with tumor growth during the endoscopic follow-up period, predictive factors of tumor growth, disease-specific survival (DSS), and overall survival (OS) rate were retrospectively evaluated. Tumor growth was defined as an increase in tumor size of approximately ≥ 5 mm compared to the initial tumor size, as measured by endoscopy. Factors associated with tumor growth like age, sex, number of lesions, stomach location, atrophic gastritis, and initial tumor size were considered for predictive analysis.

Results

A total of 1,519 patients with 1,632 eGIMTs were enrolled in this study. The median age at the initial diagnosis of eGIMT was 66 years (range, 28–90 years), and 60% of the patients were males. The percentage of patients who underwent EUS was 16%. The tumor locations were upper in 71%, middle in 20%, and lower in 9%, with the median initial tumor size being 5 mm and 24% were ≥ 1 cm. The success rates of histological diagnosis using biopsy and EUS-FNAB for eGIMT were 12% and 87%, respectively. Among the 927 patients with 995 eGIMTs examined at least twice by endoscopy and followed up endoscopically for at least 1 year, tumor growth was observed in 3.8% (median endoscopic follow-up period, 5.3 years). Of these, 33 patients underwent surgery or endoscopic resection, and the final pathological diagnoses of eGIMT were 4 high-risk GISTs, 1 intermediate-risk GISTs, 15 low-risk GISTs, 9 very low-risk GISTs, and 3 schwannomas. In univariate analysis, the only predictive factor of tumor growth was initial tumor size (< 1 cm: 1% vs. ≥ 1 cm: 14%, p < 0.0001). The 5–year DSS and 5–year OS rates of all patients with an eGIMT < 2 cm were 100% and 86%, respectively (median follow-up period, 5.2 years).

Conclusion

The long-term outcomes of patients with an eGIMT < 2 cm managed according to the current guidelines were favorable. Tumor growth in patients with an eGIMT < 1 cm is rare and may allow for extended follow-up intervals.

References

1. Nishida T, Hirota S, Yanagisawa A, et al. Clinical practice guidelines for gastrointestinal stromal tumor (GIST) in Japan: English version. Int J Clin Oncol 2008;13:416-30.

Introduction

Gastric polyps are detected in approximately 3-6% of patients undergoing routine upper endoscopy. The standard approach to managing most gastrointestinal polyps is through endoscopic polypectomy, although bleeding is a common adverse event. While cold snare polypectomy (CSP) has been reported as a safe alternative to hot snare polypectomy (HSP) for removing small colorectal polyps, further evidence is necessary to validate its effectiveness and safety specifically for gastric polyps.

Aims & Methods

Aim: Compare the efficacy and safety of CSP and HSP for removing small gastric polyps (5-15mm).
Materials and Methods: Cross-sectional study, with a prospective enrollment, including 330 consecutive gastric endoscopic polypectomies conducted in a tertiary center, between January 2021 and December 2023. Patients who underwent either CSP or HSP for gastric polyps ranging from 5 to 15 mm in size were enrolled, while those with underlying polyposis syndromes were excluded. Dedicated snares were utilized for CSP procedures. A 30-day phone survey was carried out to evaluate post-polypectomy adverse events. Statistical analysis was performed using the SPSS software v28.

Results

Overall, 330 gastric lesions in 218 patients were removed through snare polypectomy (CSP-165 lesions; HSP-165 lesions), mainly located in the body (51.5%). The median lesion size was 8.0 mm (IQR 4.0) and 8.0 mm (IQR 3.0) for CSP and HSP, respectively (p=0.08), ranging from 5 to 15 mm in both groups. The most common histological diagnoses were hyperplastic (58.2%) and fundic gland (29.4%) polyps. While the complete endoscopic resection rate was 100% in both groups, the en-bloc resection rate was slightly higher for CSP (CSP 98.2% vs. HSP 97.6%; p=0.45). At histological analysis, the complete (R0) resection rate was equal for both groups (CSP 98.2% vs. CSP 98.2%; p=1.00). Immediate bleeding, endoscopically treated, was more common with HSP (CSP 2.4% vs. HSP 3.6%; p=0.52). Delayed bleeding occurred exclusively in the HSP group (CSP 0.0% vs. HSP 1.2%; p=0.16). There were no perforations or procedure-related deaths. At univariate analysis, piecemeal resection (OR 64.6; 95%CI [3.5-1184.8]; p=0.005) was associated with a higher risk of delayed bleeding.

Conclusion

CSP demonstrates comparable effectiveness and potentially greater safety profile compared to HSP for gastric polypectomy. Consequently, CSP was non-inferior to HSP and may serve as an additional option for the removal of gastric polyps sized ≤15mm. Piecemeal resection is a hypothetical risk factor for delayed post-polypectomy bleeding.

Introduction

Polypoid lesions in Helicobacter pylori (Hp)-naive stomachs are generally fundic gland polyps (FGPs), which have a smooth surface and typically do not require treatment. However, some lesions with different appearances, such as foveolar-type adenomas that present with a reddish color and papillary surface structure, may also be observed. These lesions can be difficult to diagnose accurately with biopsy alone. An efficient and safe diagnostic and therapeutic approach for these lesions is needed.

Aims & Methods

We devised outpatient underwater cold snare polypectomy (uCSP) as a diagnostic alternative to biopsy for reddish polypoid lesions in Hp-naive stomachs that differ from the typical appearance of FGPs. We retrospectively analyzed the clinicopathological characteristics and outcomes of cases in which outpatient uCSP was performed for solitary lesions ≤10 mm in size, after obtaining informed consent. Hp-naive was defined by the absence of endoscopic and histological atrophic changes, no history of eradication therapy, and negative results from at least two different diagnostic tests for H. pylori infection.

Results

Between April 2021 and March 2025, 35 cases underwent uCSP (16 males, 19 females; mean age: 55.9 years). The mean lesion size was 3.7 mm, with 21 lesions located in the upper part of stomach and 14 in the middle part of stomach. In all cases, lesions were obtained including surrounding mucosa with minimal crush artifact to the deep mucosal layer or superficial muscularis mucosae. Histopathological diagnoses included foveolar-type adenoma in 28 cases, foveolar hyperplastic polyp in 3, FGP with dysplasia in 2, oxyntic adenoma in 1, and inflammatory polyp in 1. Among the 31 neoplastic lesions, only the oxyntic adenoma case had a positive vertical margin, yet no residual or recurrent lesion was detected during 1-year follow-up. The remaining 30 cases had negative lateral and vertical margins. No postoperative bleeding or other adverse events were observed, regardless of proton pump inhibitor use or clip closure following resection.

Conclusion

Outpatient uCSP appears to be a minimally invasive, safe, and effective diagnostic and therapeutic option for solitary polypoid neoplastic lesions ≤10 mm in Hp-naive stomachs.

Introduction

Polypectomy is a common endoscopic procedure with cold snare and hot snare techniques being widely used. Hot snare polypectomy involves cautery, which may increase the risk of thermal injury and related complications. Cold snare polypectomy has a well-established safety and efficacy profile for small colonic polyps, however, comparative data on the clinical outcomes of these two methods for gastric polyps remains limited.

Aims & Methods

A retrospective analysis was conducted on 161 consecutive gastric polypectomies for polyps under 10mm, comprising a sample of 41 patients that underwent cold snare polypectomy and 120 patients that underwent hot polypectomy over a period of 5 years.

Results

The mean polyp size differed significantly between groups, being smaller in the cold snare group (5.20 ± 1.18 mm vs 6.34 ± 1.49 mm; p < 0.001). The Charlson Comorbidity Index averaged 3 points, with no significant differences between the groups regarding the use of anticoagulant or antiplatelet therapy. Statistically significant differences were observed in both the location and histological type of the polyps between the two techniques (p = 0.003 ; p < 0.001). Cold snare polypectomy was more frequently used for polyps located in the fundus and for fundic gland polyps, whereas hot snare polypectomy was more commonly utilized for polyps located in the cardia and antrum. Submucosal injection with gelofusine and adrenaline were more frequently associated with the hot snare technique (p = 0.001). Regarding clinical outcomes, intra-procedural bleeding occurred in 16.1% of cases and was successfully managed endoscopically in all instances, mainly with clips (76.9%). No cases of delayed bleeding or perforation were observed. There were no significant differences between the groups concerning complete histological resection or polyp recurrence.

Conclusion

Cold snare polypectomy demonstrated comparable safety and efficacy to hot snare polypectomy in the resection of small gastric polyps, possibly representing a preferable approach to avoid thermal injury and related complications.