Introduction

CSDP (Cold Snare Defect Polypectomy) after CSP (Cold Snare Polypectomy) for colorectal lesions has been reported to be a factor related to pathological incomplete resection because it causes incomplete mucosal resection and specimen fragmentation. When CSP is performed, it is difficult to resect only with snaring, so it may be necessary for the endoscopist to pull the snare sometimes. However, There is no previous reports about CSP with this technique, and no study has examined “Forced” CSP (FCSP). We have the impression that CSDP is often recognized empirically in FCSP, and we investigated the frequency, safety, and validity of FCSP.

Aims & Methods

A prospective observational study was conducted with the primary endpoint being the frequency of FCSP among the CSPs performed at our hospital from November 2020 to June 2021. The patients were classified into the FCSP group and the conventional CSP group (CCSP). The rate of perforation was evaluated for safety, and the incidence of CSDP and the rate of unclear pathological margins were evaluated for validity.

Results

CSP was performed in 1391 lesions, and Forced CSP was performed in 110 lesions (7.9%). There were no cases of perforation, but CSDP was significantly higher in the Forced CSP group (96.4% (106/110) vs 6% (77/1281), p<0.001), and cases with unclear pathological margins were also used. It was significantly higher in the Forced CSP group (12.7% (14/110) vs 5.7% (75/1279), p=0.0126). In an investigation of predictors for the need for Forced CSP, cecal polyps (OR, 2.6; 95% CI=1.483-4.55; p<0.001) and polyps ≥6 mm (OR, 11.36; 95% CI=7.277 -17.727; p<0.001) was identified as an independent related factor in the multivariate analysis.

Conclusion

FCSP does not affect the complication rate, but the incidence of CSDP and the rate of unclear pathological margins are significantly high. Further investigation at multiple institutions is desired in the future.

Introduction

Endoscopic treatment of the colorectal lesions involving the diverticulum is difficult, due to the lack of muscular layer. There have been no investigations of the safety and feasibility of treatment strategy for the polyp close to or extending into the diverticulum. We investigated the outcomes of our treatment strategy for involving the diverticulum and verify the safety and the feasibility of our strategy.

Aims & Methods

Between November 2014 and January 2022, 33 cases of 33 diverticular polyp (16 males/17 females, age were 74 (54-92) years old) were enrolled in this study. Our treatment strategy for the colorectal lesions involving the diverticulum is determined by the location of polyps and diverticulum, the size of polyp, and the potential of malignancy. Cold polypectomy (CP) and gel-immersion EMR (GIEMR) are selected for the benign polyp of 10 mm or less that can be snared. The polyp with large diverticular openings, we try to inverted diverticulum.When snaring is difficult, ESD is performed. The lesions close to the diverticular opening could be resected by first incising and trimming the area close to the diverticular opening. When lesions extending into the diverticulum, ESD with the ring thread traction is performed. If traction alone cannot complete the procedure, ESD with a minor incision in the muscular layer is used in combination with traction.

Results

3 cases of CSP, 8 cases of GI EMR, and 22 cases of ESD were performed. All cases in which CSP was performed were flat type, two polyps were located in the ascending colon and one in the sigmoid colon, the median size of polyps is 3 (3-5) mm, and all polyps were adenomas. The median time of treatment was 3 (2-5) minutes, en-bloc resection was achieved in all cases, and resected margins were all negative. GI EMR: Endoscopic classification were flat type lesions in 5 cases and elevated type lesions in 3, Four polyps were located in the ascending colon and one each in the cecum, transverse colon, descending colon, sigmoid colon, the median size of lesions is 10 (8-15) mm, the pathological findings were adenomas in 5 cases and SSLs in 3 cases. The median time of treatment was 5 (2-10) minutes, en bloc resection in all cases, and margins were negative. ESD: Of the 22 cases, 17 lesions located near the diverticular opening, and 5 lesions extended completely into the diverticulum. The lesions that extended into the diverticulum, 1 case was resected by diverticulum inversion, 3 cases by ring thread traction, and 1 case by traction with a minor incision in the muscular layer. Endoscopic classification were flat type lesions in 11, elevated type lesions in 11, 5 lesions were located in the cecum, 10 lesions in the ascending colon, one lesion in transverse colon, 6 lesions in sigmoid colon, the median size of lesions is 25 (10-108) mm, the pathological findings were adenomas in 5 cases and intramucosal carcinoma in 17 cases. The median time of treatment was 35 (14-120) minutes, the median diameter of resection was 35 (20-110) mm, no complications were observed, and the horizontal margins were negative.

Conclusion

Endoscopic treatment can be performed safely by selecting a treatment method/strategy suitable for the characteristics of the colorectal lesions involving the diverticulum.

Introduction

ESD of the colorectal lesions involving the appendiceal orifice (AO) is technically challenging because of the thin wall and narrow working space. On the other hand, even if the lesions are small and benign, it is difficult to perform EMR because of the narrow snaring space. We previously reported strip biopsy (SB) resection of the AO lesion. The SB technique is as follows (1) Insert a 2-channel scope and check the lesion. (2) Insert a snare and grasping forceps into each channel, and hold the grasping forceps in the snare. (3) Grasp the appendiceal end of the lesion with the grasping forceps, open the snare, grasp the lesion, and resect it. This method makes it possible to snare the lesion after confirming the distal border of the AO. In the present study, we evaluated the feasibility of SB for AO lesions.

Aims & Methods

This was a retrospective study in which SB for AO lesions was performed on 10 patients at our hospital. Inclusion criteria for the study cohort were (1) the lesion less than 15 mm, and (2) visible lesion margin on the appendicular side. Polyps suspected to be cancerous were excluded.

Results

Male to female ratio was 8:2, median age (range) was 76 years (44-89). The median tumor size was 10 mm (10-15). The pathological findings were 8 cases of SSL and 2 cases of low-grade tubular adenoma. All lesions were resected en bloc, with a median treatment time of 10 minutes (range (5-10)). No complications were observed. Pathology results were negative for 8 cases and unknown for 2 cases. All lesions were resected endoscopically with no residuals.

Conclusion

SB technique for AO lesions is safe and it appeared that this could be one option for endoscopic treatment of AO lesions.^​

Introduction

The degree of fibrosis during colorectal ESD varies and sometimes makes the procedure itself difficult. Preoperative prediction of fibrosis is expected to help develop a reliable strategy.

Aims & Methods

Of 1309 colorectal ESD lesions performed at our hospital between April 2012 and September 2022, 953 lesions larger than 20 mm were included after excluding post-treatment recurrence, SMT, and other conditions. Intraoperative fibrosis was classified into F0 (none), F1 (mild), and F2 (severe).

Results

Fibrosis was observed in 192 (20.1%) patients (F1; 143, F2; 49). The tumor diameter (median, range) was 23 (20-135), 30 (20-210), and 35 (20-115) mm in F0, F1, and F2 groups, respectively. The rate of the cecum (%) was 13.3 : 29.4 : 16.3, which was higher in F1. Overall, bleeding was observed in 17 patients (1.8%) and perforation in 3 patients (0.3%), and the frequency was similar in each group. The curative resection rate (%) was 98.4:91.6:59.2, with F2 being significantly inferior. The long treatment time (≥120 minutes) (%) was 1.7 : 9.1 : 46.9, showing a significant difference between F0 vs F1 and F1 vs F2, and the dissection speed (mean±SD, mm²/min) was 25.9±14.5 : 23.2±13.6 : 15.3±10.6, which was significantly slower in F2. The predictive factors of F1 and F2: straddling the folds, prior biopsy, lesion diameter, site, and morphology, were included in the study, and multivariate analysis showed that the predictive factors of F1 were straddling folds (OR;2.07,95%CI;1.39-3.11), lesion diameter ≥50mm (OR;4.68,95%CI;2.45-8.94), biopsy (OR;6.44,95%CI;3.32-12.5), NGPD (OR;4.31,95%CI;2.37-7.83), and cecum(OR;3.73,95%CI;2.35-5.92). The predictive factors of F2 were straddling folds (OR;2.34,95%CI;1.21-4.51), lesion diameter ≥50 mm (OR;7.29,95%CI;3.03-17.5), biopsy (OR;5.07,95%CI;1.81-14.1), and protruded type (OR;6.44,95%CI;3.23-12.8).

Conclusion

Colorectal ESD for fibrotic lesions was safe, but the curative resection rate was low in F2. F1-specific predictors were cecum and NGPD, and F2-specific predictors were protruded type, suggesting that the choice of surgeon and strategy should depend on the expected degree of fibrosis.

Introduction

While cold snare polypectomy (CSP) has been proven effective and safe in the resection of small polyps, it is not actively recommended for the pedunculated (Ip type) polyps in the European Society and Gastrointestinal Endoscopy and US Multi-Society Task Force on Colorectal Cancer guidelines. Although Japanese guidelines recommend that CSP should be limited to lesions less than 10 mm, preoperatively diagnosed as adenomas, the guideline does not address how to resect pedunculated (Ip type) adenomas. This study aims to examine the pros and cons of CSP for the resection of Ip type adenoma.

Aims & Methods

Among patients with colorectal adenomas resected endoscopically at Nippon Medical School Hospital in Japan, from January to July 2020, 85 lesions in 67 consecutive cases of type Ip, and 762 lesions in 346 cases of non-Ip type (types Is, Isp, and II) resected by CSP, were observed. Regarding clinicopathologic features, R0 resection rate, and adverse events, we evaluated the difference in the resection method (Ip-CSP group vs Ip-hot polypectomy (HP)/EMR group) as Study 1; and the macroscopic classifications (Ip-CSP group vs Non-Ip-CSP group) as Study 2.

Results

In Study 1, 23 lesions were included in the Ip-CSP group and 62 lesions were included in the Ip-HP/EMR group. A higher percentage of proximal colon lesions (74% vs. 27%, p<0.001) and smaller mean tumor size (5.1±1.6mm vs. 11±5.0mm, p<0.001) were observed in the Ip-CSP group, compared to Ip-hot polypectomy (HP)/EMR group. The R0 resection rate was also significantly lower in Ip-CSP group (61% vs. 90%, p=0.03). While the R0 resection rate tended to be low for lesions 6 mm or greater (67%/93%), no difference was observed among lesions less than 5 mm (59%/50%). No perforation or postoperative bleeding was observed in both groups. In Study 2 using 23 lesions for the Ip-CSP group and 762 lesions for the Non-Ip-CSP group, no significant difference was observed in tumor location or mean tumor diameter, as well as R0 resection rates (61% vs. 45%, p=0.13). No perforation was observed in either group. Postoperative bleeding was observed only in the Non-Ip group for 5 lesions (0.7%).

Conclusion

To achieve pathological complete resection for Ip adenomas, HP/EMR should be selected for adenoma with a diameter of 6 mm or greater. Conversely, CSP was considered acceptable for lesions of 5 mm or less. Further studies with a larger number of patients are warranted.

Introduction

Cold snare polypectomy (CSP) has become popular as a safe and simple treatment for small colonic lesions. According to the Japanese guidelines, CSP is indicated for adenomas <10 mm with no suspicion of carcinoma [1]. Occasionally, colorectal carcinoma is diagnosed after resection, and there is no consensus on the treatment of such lesions [2-4].

Aims & Methods

This single-center retrospective study aimed to investigate the long-term prognosis of Japanese patients with pathologically diagnosed colorectal carcinoma after resection by CSP. Patients who underwent CSP for small colonic lesions at our hospital in 2013–2022 and were histopathologically diagnosed with colorectal carcinoma were included in this study. We examined the local residual or recurrence rate, scar detection rate, and recurrence-free survival rate in patients who underwent at least one colonoscopy after CSP.

Results

Out of 12,935 lesions (6,082 cases) that were resected using CSP during the study period, 81 lesions (0.63%; 81 cases) were histologically diagnosed as colorectal carcinoma (mean age, 69.7 years; male patients, 69% [56/81]). Histologically, all tumours were well-differentiated adenocarcinomas. Negative lateral and vertical margins of the resected specimens were 47% (38/81) and 72% (58/81), respectively. Of these 81 cases, 47 (58%) were followed up at least once by colonoscopy. The breakdown of cases that were not followed up endoscopically is as follows: concurrent advanced cancer (n=15), advanced age (n=7), dropout (n=7), and others (n=5). Endoscopic evidence of residual disease or recurrence was found in 1/47 patients (2%), and the remaining 46 patients had a median colonoscopic follow-up of 425 days (interquartile range, 192.5–1078.5 days) with no endoscopic evidence of local recurrence. In 51% (24/47) of cases, post-polypectomy scars could be identified. In one case where local residual carcinoma was confirmed, a retrospective review of the CSP revealed incomplete resection at the time of treatment. Abdominal CT performed immediately after CSP showed coincidental peritoneal dissemination, and the patient died 177 days after diagnosis. In 46 patients with no endoscopic evidence of local recurrence, the median observation period was 921 days (interquartile range, 475–1654.5 days), with six cases of death from causes other than colorectal cancer, and the others were alive without recurrence.

Conclusion

The frequency of residual disease or recurrence of colorectal carcinoma treated by CSP was low, and the long-term prognosis was favourable once the absence of residual lesions was confirmed endoscopically.

References

1. Uraoka T, Takizawa K, Tanaka S et al. Guidelines for Colorectal Cold Polypectomy (supplement to "Guidelines for Colorectal Endoscopic Submucosal Dissection/Endoscopic Mucosal Resection"). Dig Endosc 2022; 34: 668-675.
2. Yoshii S, Hayashi Y, Nakamura T et al. Endoscopic features and clinical course of colorectal carcinoma resected by cold snare polypectomy. J Gastroenterol Hepatol 2023, in press
3. Inoki K, Takamaru H, Furuhashi H et al. Management of colorectal high-grade dysplasia or cancer resected by cold snare polypectomy: a multicenter exploratory study. J Gastroenterol 2023, in press
4. Yoshida N, Fukumoto K, Hasegawa D et al. Recurrence rate and lesions characteristics after cold snare polypectomy of high-grade dysplasia and T1 lesions: A multicenter analysis. J Gastroenterol Hepatol 2021; 36: 3337-3344.