Endoscopic submucosal dissection of large colorectal tumors by using a novel spring-action S-O clip for traction (with video)

Characteristics of positive horizontal margins in patients who underwent colorectal endoscopic submucosal dissection

Objectives

Endoscopic submucosal dissection (ESD) enables en bloc resection of colorectal neoplasms, but occasionally results in positive horizontal margins (HMs). However, the site of the resected specimen that tends to be positive for HM has not been investigated. We aimed to clarify the characteristics associated with HMs in lesions resected en bloc with ESD.

Methods

Patients with colorectal neoplasms who underwent en bloc resection with ESD were included in this study. The patients were divided into negative HMs (HM0) and positive or indeterminate HMs (HM1) groups. The characteristics associated with HM1 resection were investigated. In addition, the local recurrence rate during endoscopic follow-up for >6 months after ESD was observed.

Results

In total, 201 lesions were analyzed in 189 patients (HM0, 189 lesions; HM1, 12 lesions). The HM1 group had a significantly larger median lesion diameter (25 vs. 55 mm; p < 0.001) and more lesions with >50% circumference than did the HM0 group (p < 0.001). Furthermore, the prevalence of severe fibrosis was significantly higher in the HM1 group than in the HM0 group (p < 0.001). Positive horizontal sites of the resected specimens were more frequent at the oral and anal sites than at the lateral sites. No local recurrences were observed in either group.

Conclusions

The characteristics associated with HM1 depended on lesion size, particularly lesions with >50% circumference, and submucosal fibrosis.

Animal experimental study on magnetic anchor technique-assisted endoscopic submucosal dissection of early gastric cancer

BACKGROUND

Gastric cancer (GC) has high morbidity and mortality. Moreover, because GC has no typical symptoms in the early stages, most cases are already in the advanced stages by the time the symptoms appear, thus resulting in poor prognosis and a low survival rate. Endoscopic submucosal dissection (ESD) can realize the early detection and diagnosis of GC and become the main surgical method for early GC. However, ESD has a steep learning curve and high technical skill requirements for endoscopists, which is not conducive to its widespread implementation and advancement. Therefore, a series of auxiliary techniques have been derived.

AIM

To evaluate the safety and efficacy of magnetic anchor technique (MAT)-assisted ESD in early GC.

METHODS

This was an ex vivo animal experiment. The experimental models were the isolated stomachs of pigs, which were divided into two groups, namely the study group (n = 6) with MAT-assisted ESD and the control group (n = 6) with traditional ESD. Comparing the total surgical time, incidence of surgical complications, complete mucosal resection rate, specimen size, and the scores of endoscopist’s satisfaction with the procedure reflected their feelings about convenience during the surgical procedure between the two groups. The magnetic anchor device for auxiliary ESD in the study group comprised three parts, an anchor magnet (AM), a target magnet (TM), and a soft tissue clip. Under gastroscopic guidance, the soft tissue clip and the TM were delivered to the pre-marked mucosal lesion through the gastroscopic operating hole. The soft tissue clip and the TM were connected by a thin wire through the TM tail structure. The soft tissue clip was released by manipulating the operating handle of the soft tissue clip in a way that the soft tissue clip and the TM were fixed to the lesion mucosa. In vitro, ESD is aided by maneuvering the AM such that the mucosal dissection surface is exposed.

RESULTS

The total surgical time was shorter in the study group than in the control group (26.57 ± 0.19 vs 29.97 ± 0.28, P < 0.001), and the scores of endoscopist’s satisfaction with the procedure were higher in the study group than in the control group (9.53 ± 0.10 vs 8.00 ± 0.22, P < 0.001). During the operation in the study group, there was no detachment of the soft tissue clip and TM and no mucosal tearing. The magnetic force between the AM and TM provided good mucosal exposure and sufficient tissue tension for ESD. The mucosal lesion was completely peeled off, and the operation was successful. There were no significant differences in the incidence of surgical complications (100% vs 83.3%), complete mucosal resection rate (100% vs 66.7%, P = 0.439), and specimen size (2.44 ± 0.04 cm vs 2.49 ± 0.02, P = 0.328) between the two groups.

CONCLUSION

MAT-ESD is safe and effective for early GC. It provides a preliminary basis for subsequent internal animal experiments and clinical research.

Underwater endoscopic submucosal dissection for colorectal tumors decreases the incidence of post-electrocoagulation syndrome

BACKGROUND AND AIMS

Underwater endoscopic submucosal dissection (U-ESD) is a recently developed procedure that has the potential to prevent post-ESD coagulation syndrome (PECS) owing to its heat-sink effect. We aimed to clarify whether U-ESD decreases the incidence of PECS compared with conventional ESD (C-ESD).

METHODS

A total of 205 patients who underwent colorectal ESD (C-ESD: 125; U-ESD: 80) were analyzed. Propensity score matching analysis was performed to adjust for patient backgrounds. Ten C-ESD and two U-ESD patients with muscle damage or perforation during ESD were excluded when comparing PECS. The primary outcome was to compare the incidence of PECS between the U-ESD and C-ESD groups (54 matched pairs). Secondary outcomes were to compare procedural outcomes between the C-ESD and U-ESD groups (62 matched pairs).

RESULTS

Among the 78 patients who underwent U-ESD, PECS occurred in only one patient (1.3%). Adjusted comparisons between the U-ESD and C-ESD groups demonstrated a significantly lower incidence of PECS in the U-ESD group (0% vs 11.1%; P = 0.027). Median dissection speed was significantly faster in the U-ESD than in the C-ESD group (10.9 mm2 /min vs 6.9 mm2 /min; P < 0.001). En bloc and complete resection rates were 100% in the U-ESD group. Although perforation and delayed bleeding occurred in one patient each (1.6%) as adverse events in the U-ESD group, there were no differences compared with the C-ESD group.

CONCLUSIONS

Our study demonstrates that U-ESD effectively decreases the incidence of PECS and is a faster and safer method for colorectal ESD.

Multicenter randomized control study of the efficacy of SO clip in colorectal endoscopic submucosal dissection (ESD). (SO clip study in colorectal ESD): Randomized controlled trial

INTRODUCTION

Endoscopic submucosal dissection (ESD) allows the en bloc resection of colorectal epithelial tumors regardless of size. Although ESD is minimally invasive and yields favorable outcomes, it is technically difficult and requires a long procedure time. In addition, colorectal ESD is associated with a particularly high risk of complications, due to the thin bowel wall, bowel flexion, and peristalsis.Direct visualization of the submucosal layer by traction of the lesion after mucosal dissection would make ESD performance easier. S-O clips traction lesions toward the lumen, facilitating direct visualization of the submucosal layer, resulting in efficient dissection due to the traction effect and adequate dissection depth. Use of this traction device can contribute to shortening the procedure time and reducing the risk of complications. This multicenter randomized controlled trial will evaluate the usefulness of the S-O clip in colorectal ESD and assess the procedure time and frequency of complications associated with the procedure.

METHODS/DESIGN

This multicenter, randomized control trial will enroll 200 patients at 4 hospitals in Japan undergoing ESD for colorectal epithelial tumors. Patients who meet the inclusion and exclusion criteria will be randomized to undergo ESD using S-O clips or conventional ESD. Patients will be randomized by a computer-generated random sequence with stratification by operator experience (trainee or expert), tumor location (colon/rectum), and institution. The primary endpoint will be ESD procedure time, defined as the time from the start of the local injection into the submucosal layer to the end of dissection. Other outcomes will include the rates of procedural complications, en bloc resection and cure.

DISCUSSION

ESD using the S-O clip is expected to shorten procedure time, reduce the incidence of adverse events, and standardize the procedure. This study may resolve clinical questions about whether ESD using the S-O clip traction device is more effective and safer than conventional ESD.

Endoscopic submucosal tunnel dissection vs conventional endoscopic submucosal dissection for large colorectal neoplasms: a single-centre retrospective study

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) is still not widely used due to its technical difficulty and the risk of complications. Several techniques, such as traction techniques, pocket techniques and others, have been proposed to facilitate it. One modified pocket technique especially suitable for large lesions is endoscopic submucosal tunnel dissection (ESTD). The aim of this study was to evaluate the safety and efficacy of ESTD and compare ESTD to the conventional ESD (CESD) for treating large colorectal lesions.

METHODS

The charts of consecutive patients referred to the Arcispedale Santa Maria Nuova (Reggio Emilia, Italy) for colorectal ESD between January 2014 and February 2021 for colorectal neoplasms > 40 mm were retrospectively analysed. The primary outcome of the study was the en bloc resection rate. Secondary outcomes were complete and curative resection rates, procedure speed, the adverse events rate and the recurrence rate.

RESULTS

There were 59 patients (M:F ratio 29:30, median age 70 years [range 50-93 years]). Of 59 colorectal lesions > 40 mm, 25 were removed by ESTD and 34 by CESD. The en bloc resection rate was 100% in both groups and the complete resection rate was similar (ESTD 92% vs CESD 97.1%, p = 0.569), while the curative resection rate was higher in the CESD group, but not significantly (94.1% vs 76%, p = 0.061). Procedure speed was significantly faster with ESTD (22 vs 17 mm²/min, p = 0.045), and the overall incidence of adverse events was low (6.8%). Eight patients were referred to surgery due to non-curative resection. During follow-up, no recurrence was observed in either treatment group.

CONCLUSION

ESTD achieves a very high en bloc resection rate and is faster than CESD.

Novel closure method for a large mucosal defect after endoscopic resection: String clip suturing method with an anchor

Duodenal endoscopic submucosal dissection (ESD) is a high-risk technique; however, prophylactic closure of mucosal defects reduces the risk. Unfortunately, we have encountered cases where closure is difficult, especially in large lesions. Therefore, we developed a novel closure technique, a string clip suturing method with an anchor (SCSM-A). This study aimed to elucidate the feasibility of this method. Five patients underwent this method for the closure of mucosal defects after duodenal ESD. The initial string clip was deployed at the anal end of the mucosal defects and the second clip was deployed at the other end of the mucosal defect. A third clip was deployed on the muscular layer in the middle of the mucosal defect. The free end of the string was pulled, and additional clips were deployed around the first to the third clips for complete closure. Because of grasping the muscle layer, SCSM-A can be employed for secure closure without creating a pocket. We reviewed the background and clinical course of hospitalization of patients who underwent this method. The resected specimens ranged from 52 to 103 mm in diameter. Complete closure of the mucosal defects was possible in all the cases. There were no adverse events, and no cases required additional treatment. All the patients were discharged within 7 days. The new method achieved secure closure even for large mucosal defects after duodenal ESD. This is a technique that can be applied to other organs, e.g., the colon.

Impact of Traction Direction in Traction-Assisted Gastric Endoscopic Submucosal Dissection (with Videos)

BACKGROUND

The impact of traction direction in traction-assisted gastric endoscopic submucosal dissection (ESD) has not been adequately investigated. A clip with line (CWL) is a classical single-directional traction device. In contrast, a spring and loop with clip (SLC; S-O clip) is a newly developed multidirectional traction device.

AIMS

To investigate the impact of traction direction in gastric ESD by comparing the procedure-related outcomes of CWL-assisted ESD (CWL-ESD) and SLC-assisted ESD (SLC-ESD).

METHODS

We retrospectively examined 140 patients with superficial gastric neoplasms who underwent SLC-ESD or CWL-ESD by a single ESD expert during November 2017-September 2020. The traction direction was classified based on the endoscopic finding in the following five categories: proximal, diagonally proximal, vertical, diagonally distal, and distal. In SLC-ESD, we set vertical traction, using the multidirectional traction function. Propensity score matching was conducted to compensate for the differences in lesion size, injection function of electrosurgical knife, ulcerative lesion, lesion location, and lesion position. The primary outcome was gastric ESD procedure time.

RESULTS

Propensity score matching created 42 pairs. The median gastric ESD procedure time in the SLC-ESD group was significantly shorter than that in the CWL-ESD group (28.3 min vs. 51.0 min, P = 0.022). All traction direction in the SLC-ESD group was vertical, while only 16.7% in the CWL-ESD group. En bloc resection was attained without perforation in all the patients in both groups.

CONCLUSION

Our findings suggest that SLC can provide vertical traction, which reduces the gastric ESD procedure time. Multidirectional traction devices can provide vertical traction in most cases of gastric ESD, unlike single-directional traction devices. Vertical traction may reduce the gastric ESD procedure time.

Injury to the muscle layer, increasing the risk of post-colorectal endoscopic submucosal dissection electrocoagulation syndrome

BACKGROUND AND AIM

In colorectal endoscopic submucosal dissection (ESD), post-ESD electrocoagulation syndrome (PECS) has been recognized as one of the major complications. There are no reports on the relationships between ESD findings and PECS. This study aims to evaluate the risk factors for PECS, including ESD findings such as muscularis propria exposure.

METHODS

We performed a retrospective cohort study of patients who underwent colorectal ESD between January 2017 and December 2021 in Japan. The grade of injury to the muscle layer caused by ESD was categorized as follows: Grade 0, no exposure of muscularis propria; Grade 1, muscularis propria exposure; Grade 2, torn muscularis propria; and Grade 3, colon perforation. The risk factors for PECS, including injury to the muscle layer, were analyzed by univariate and multivariate analyses.

RESULTS

Out of 314 patients who underwent colorectal ESD, PECS occurred in 28 patients (8.9%). The multivariate analysis showed that female sex (odds ratio [OR] 3.233; 95% confidence interval [95% CI]: 1.264-8.265, P = 0.014), large specimen size (≥ 40 mm) (OR 6.138; 95% CI: 1.317-28.596, P = 0.021), long procedure time (≥ 90 min) (OR 2.664; 95% CI: 1.053-6.742, P = 0.039), and Grade 1 or 2 injury to the muscle layer (OR 3.850; 95% CI: 1.090-13.61, P = 0.036) were independent risk factors for PECS.

CONCLUSIONS

Injury to the muscle layer, such as exposure or tear, was identified as a novel independent risk factor for PECS. We should perform colorectal ESD carefully to avoid injuring the muscle layers.

Comparison of efficiency and safety between dual-clip and rubber band-assisted ESD and conventional ESD for colonic lateral spreading tumors (LSTs) with different levels of technical difficulty: a retrospective case–control study

Background

Dual-clip and rubber band-assisted endoscopic submucosal dissection (DCRB-ESD) is a useful technique in the management of lateral spreading tumors (LSTs) of the colon and is suggested by researchers compared with conventional ESD (C-ESD). The aim of this retrospective study is to further analyze the efficiency and safety of DCRB-ESD in a setting with varying technical difficulties.

Methods

Patients who underwent endoscopic treatment (DCRB-ESD or C-ESD) due to LSTs between Jan 1st, 2019 and Jan 1st, 2022, were retrospectively collected. Patients were classified into the following two groups: the DCRB-ESD group (n = 46) and the C-ESD group (n = 81). Baselines were compared and propensity score matching (PSM) was employed to manage the heterogeneity. The technical difficulty and outcomes of the two groups were evaluated based on a semiquantitative model (CS-CRESD) previously described.

Results

The baseline characteristics of the two groups were balanced except sex and LST classification before PSM and were corrected after PSM. The median ESD operation time of DCRB-ESD was shorter than that of C-ESD (32 vs 41 and 30 vs 44 before and after PSM respectively, P < 0.05). The operation durations of cases with different CS-CRESD scores were different (P < 0.05). In the subgroup with a score of 0, DCRB-ESD showed no advantage than C-ESD in terms of operation duration before and after PSM. In subgroups with a score of 1–3, DCRB-ESD was faster than C-ESD. In subgroups with a score of 4–5, the between-group operation duration was not significantly different due to the limited number of cases, although the median time of DCRB-ESD was shorter. The R0 resection rates, curative resection, complications, and additional surgery in both groups were not significantly different. No adverse events, such as a clip falling off or rubber band rupturing occurred during this study.

Conclusion

DCRB-ESD was an efficient and safe procedure in the management of colonic LSTs. With DCRB-ESD, the operation duration of difficult cases can be shortened without sacrificing complication risk. However, not all cases would benefit from DCRB-ESD. For easy cases (CS-CRESD score = 0), DCRB-ESD may not be prior to C-ESD by experienced endoscopists. A pre-ESD technical difficulty evaluation was recommended to decide whether to perform DCRB-ESD or not.

Application of in vivo traction-assisted resection of proximal colon lesions: a case series (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is the treatment of choice for colorectal neoplasms in Japan. ESD can completely peel off the lesion and is associated with a significantly lower recurrence rate of colorectal cancers than EMR and is widely used to treat gastrointestinal tumors. This study aimed to evaluate in vivo traction in endoscopic submucosal dissection (ESD) of proximal colon lesions.

METHODS

This retrospective study included patients with lesions in the proximal colon who received ESD treatment at Qilu Hospital of Shandong University from June 2018 to December 2020. Patients were divided into two groups according to the in vivo traction method (orthodontic ring or elastic ring) during operation. The operation time, dissection time, proportion of complete resection of lesions, and complications were compared between the two groups.

RESULTS

There were 28 patients in this study. In the orthodontic ring group (n = 10), the average lesion diameter was 2.0-2.5 cm, and the average operation and dissection times were 26.5 ± 7.47 and 21.5 ± 7.47 min, respectively. In the elastic ring group (n = 18), the average lesion diameter was 2.5-5.5 cm, and the average operation and dissection times were 27.39 ± 11.83 and 22.39 ± 11.83 min, respectively. All lesions were completely resected in a single operation, and no wound perforation and delayed bleeding occurred.

CONCLUSION

In vivo traction-assisted ESD can be used to resect proximal colon lesions in selected patients (precancerous lesions and early colon cancer limited to the mucosa or with a submucosa infiltration depth of < 1000 µm).

Underwater endoscopic submucosal dissection and hybrid endoscopic submucosal dissection as rescue therapy in difficult colorectal cases

Background and study aims  Colorectal endoscopic submucosal dissection (ESD) is still not widely used due to its technical difficulty and the risk of complications. Rescue therapies such as hybrid ESD (H-ESD) have been proposed for very difficult cases, as has underwater ESD (U-ESD). This study evaluated the safety and efficacy of H-ESD and U-ESD in difficult cases. Patients and methods  The hospital charts of consecutive patients referred for colorectal ESD between January 2014 and February 2021 because they were considered difficult cases were retrospectively analyzed. The primary outcome of the study was en bloc resection rate; secondary outcomes were the rate of complete resection, procedure speed, and incidence of adverse events (AEs). Results  Fifty-nine colorectal neoplasms were considered, 22 of which were removed by U-ESD and 37 by H-ESD. The en bloc resection rate in the U-ESD group was 100 %, while it was 59.5 % in the H-ESD group. Dissection speed was 17.7mm ² /min in the U-ESD group and 8.3 mm ² /min in the H-ESD group. The AE rate was low in the U-ESD group and moderately high during H-ESD (5 % and 21.6 %, respectively; and perforation rate 0 % and 10.8 %, respectively). Larger lesions were treated with U-ESD, while more fibrotic ones were treated with H-ESD. Conclusions  U-ESD and H-ESD are both effective and safe techniques in difficult colorectal situations. U-ESD is particularly effective and fast for large lesions when it is not possible to obtain comfortable knife position, while H-ESD is more suitable for very fibrotic lesions.

Effectiveness of a multi-loop traction device for colorectal endoscopic submucosal dissection performed by trainees: a pilot study

Colorectal endoscopic submucosal dissection (ESD) is a difficult procedure, and its introduction to trainees has been debated. Although the criteria for performing colorectal ESD vary among institutions, it is often allowed after gaining experience performing surgeries in animals and upper gastrointestinal ESD. This pilot study aimed to compare the treatment outcomes of ESD performed by trainees using the multi-loop traction device (MLTD group) and those of conventional ESD performed by experts (control group). It also aimed to determine whether the MLTD can be used to safely introduce colorectal ESD to trainees. We included 26 colorectal ESD patients (13 in the MLTD group and 13 in the control group) treated at our hospital from October to December 2021. There were no significant differences in the procedure time (50 min vs. 30 min), dissection speed (19.9 mm²/min vs. 28.7 mm²/min), and intraoperative perforation (0% vs. 0%) of the two groups. Furthermore, the rate of ESD self-completion in the MLTD group was 100%. Therefore, the use of the MLTD allowed the safe introduction of colorectal ESD, even among endoscopists with no experience performing colorectal ESD. Consequently, the use of the MLTD may replace animal and upper gastrointestinal ESD when introducing colorectal ESD to trainees.

The usefulness of a double-balloon endolumenal interventional platform for colorectal endoscopic submucosal dissection by non-expert endoscopists in a porcine model (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is an optimal treatment for colorectal tumors; however, it is technically difficult, especially for non-experts. Therefore, a device that helps non-experts perform colorectal ESD would be beneficial. A double-balloon endolumenal interventional platform (DEIP) was recently developed to assist colorectal ESD through endoscope stabilization and traction. This study assessed the usefulness of colorectal ESD using the DEIP (DEIP-ESD) by endoscopists, including non-experts, in a living porcine model.

METHODS

Two pigs were used to perform eight DEIP-ESD and eight conventional cap-assisted ESD (C-ESD) procedures. Three experts and five non-experts each resected one lesion using DEIP-ESD and one using C-ESD. We evaluated the treatment outcomes and performed stratified analyses between the experts and non-experts.

RESULTS

Dissection speed was significantly faster in DEIP-ESD than in C-ESD (13.3 mm²/min vs 28.5 mm²/min, P = 0.002). However, the total procedure time did not differ significantly between DEIP-ESD and C-ESD. In the stratified analyses, the dissection speed of non-experts was significantly faster in DEIP-ESD than in C-ESD (10.9 mm²/min vs 25.1 mm²/min, P = 0.016), while that of experts increased in DEIP-ESD but to a lesser extent (19.1 mm²/min vs 28.8 mm²/min, P = 0.1). The total procedure time did not differ between DEIP-ESD and C-ESD for both experts and non-experts. The self-completion rate of non-experts also increased in DEIP-ESD. Moreover, the number of muscularis propria injuries induced by non-experts was fewer in DEIP-ESD than in C-ESD.

CONCLUSIONS

DEIP could facilitate colorectal ESD by improving dissection efficiency without increasing adverse events, especially when performed by non-experts.

Training program using a traction device improves trainees' learning curve of colorectal endoscopic submucosal dissection

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) requires advanced endoscopic skill. For safer and more reliable ESD implementation, various traction devices have been developed in recent years. The purpose of this research was to evaluate whether an ESD training program using a traction device (TD) would contribute to the improvement of trainees' skill acquisition.

METHODS

The differences in treatment outcomes and learning curves by the training program were compared before and after the introduction of TD (control group: January 2014 to March 2016; TD group: April 2016 to June 2018).

RESULTS

A total of 316 patients were included in the analysis (TD group: 202 cases; control group: 114 cases). The number of cases required to achieve proficiency in ESD techniques was 10 in the TD group and 21 in the control group. Compared to the control group, the TD group had a significant advantage in ESD self-completion rate (73.8% vs. 58.8%), dissection speed (19.5 mm²/min vs. 15.9 mm²/min), en bloc resection rate (100% vs. 90%), and R0 resection rate (96% vs. 83%).

CONCLUSIONS

The rate of colorectal ESD self-completion by trainees improved immediately after the start of the training program using a traction device compared to the conventional method, and the dissection speed tended to increase linearly with ESD experience. We believe that ESD training using a traction device will help ESD techniques to be performed safely and reliably among trainees.

Fever and electrocoagulation syndrome after colorectal endoscopic submucosal dissection for patients with immunosuppressants and steroids

Objectives

Transient fever and electrocoagulation syndrome after colorectal endoscopic submucosal dissection (ESD) remain a challenge. The aim of this study was to assess the risk factors of post‐ESD fever and post‐ESD coagulation syndrome (PECS), focusing on the involvement of immunosuppressive drugs and steroids (IM).

Methods

This retrospective analysis included 510 patients who underwent colorectal ESD at Okayama University Hospital from 2015 to 2020. The incidence rate, clinical outcome, and factors associated with post‐ESD fever and PECS were investigated.

Results

Post‐ESD fever and PECS occurred in 63 patients (12.4%) and 43 patients (8.4%), respectively. In multivariate analysis, the American Society of Anesthesiologists Physical Status ≥3, the use of immunosuppressants or prednisolone ≥5mg (IM group), and injury to muscle layer/perforation were significantly associated with post‐ESD fever. In PECS, IM group, tumors located on the right side, treatment time ≥60 min, injury to the muscle layer, and multiple lesions were independent risk factors. Both post‐ESD fever and PECS improved conservatively in the IM group, and no serious complication was observed.

Conclusions

The use of IM was a risk factor for both post‐ESD fever and PECS. However, there were no serious complications in colorectal ESD for patients taking IM.

Randomized study of two endo-knives for the traction-assisted endoscopic submucosal dissection of early esophageal squamous cell carcinoma

Needle-type devices, such as the DualKnife (Olympus, Tokyo, Japan), are widely used for traction-assisted esophageal endoscopic submucosal dissection (ESD) but require a prolonged operation time. An improved model of the ITknife (Olympus), the ITknife nano, may allow faster and easier ESD than the DualKnife. We conducted a randomized study to compare the performances of the DualKnife and the ITknife nano for traction-assisted esophageal ESD. Patients with early esophageal squamous cell carcinoma were eligible for this study. The primary outcome was the total procedure time. The secondary outcomes were submucosal dissection time, en bloc, and complete resection rates, perforation rate, and adverse events. Results Fifty patients were equally divided into two groups: the DualKnife group (D-group) and the ITknife nano group (I-group), and all underwent the assigned treatment. The I-group had significantly shorter total procedure time (36.8 vs. 60.7 min; P < 0.01) and submucosal dissection time (17.2 vs. 35.8 min; P < 0.01) than the D-group. The en bloc and complete resection rates were sufficiently high in both groups (100% and 100% in the D-group and 100% and 96% in the I-group, respectively). Significantly fewer hemostatic procedures due to intraoperative bleeding were performed in the I-group than in the D-group (0.2 vs. 1.4; P < 0.01). Delayed bleeding, perforation, or esophageal stricture did not occur in either group. The ITknife nano exhibited lower procedure time for traction-assisted esophageal ESD than the DualKnife, without increasing adverse events.

Endoscopic submucosal dissection using traction by a spring-and-loop with clip for a laterally spreading tumor in the inferior aspect of the cecum: a nonreferral center experience

Video 1Endoscopic submucosal dissection using traction by a spring-and-loop with clip for a laterally spreading tumor in the inferior aspect of the cecum: a nonreferral center experience.

Orthodontic Rubber Band-Assisted Endoscopic Submucosal Dissection: An Efficient Method for Treating Superficial Colorectal Tumors

Background

Colorectal endoscopic submucosal dissection (ESD) is a complex operation. Effective traction is crucial. We have successfully used an orthodontic rubber band (ORB) combined with the clip traction method to assist ESD (ORB-ESD). The aim of this retrospective study is to describe the method and to compare the efficacy and safety of ORB-ESD versus conventional ESD in the treatment of superficial colorectal tumors.

Methods

We retrospectively analyzed the data of patients with superficial colorectal tumor (with diameter ≥ 20 mm) who received either ORB-ESD (n = 34) or conventional ESD (n = 90) between January 2019 and September 2020. Propensity score matching (PSM) was used to match the clinical data of 31 pairs of patients in each group.

Results

Operation time was significantly shorter for ORB-ESD than for conventional ESD (34.5 minutes vs. 56 minutes, P ≤ 0.001). In the propensity-matched cohorts, the operation time remained significantly shorter in the ORB-ESD patients (35 minutes vs. 50 minutes, P = 0.001). Postoperative adverse events, en bloc resection rate, and R0 resection rate were comparable between the two groups (P > 0.05), both before and after propensity score matching. In the ORB subgroup analysis, the trainee and expert ESD operation times were similar (37 (26–53) vs. 33.5 (26–37) minutes, respectively; P = 0.274).

Conclusion

ORB-ESD appears to be an effective technique for ESD of colorectal cancer. Our findings need to be confirmed in large prospective multicenter studies.

Advances in traction methods for endoscopic submucosal dissection: What is the best traction method and traction direction?

Endoscopic submucosal dissection (ESD) has been developed as a treatment for superficial gastrointestinal neoplasms, which can achieve en bloc resection regardless of the lesion size. However, ESD is technically difficult because endoscopists cannot bring their hand into the gastrointestinal tract, unlike surgeons in regular surgery. It is difficult to obtain sufficient tension in the dissection plane and a good field of vision. Therefore, ESD is associated with a long procedure time and a high risk of adverse events in comparison with endoscopic mucosal resection. Traction methods have been developed to provide sufficient tension for the dissection plane and a good field of vision during the ESD procedure. However, traction direction is limited in most traction methods, resulting in insufficient effect in some cases. Although traction direction is considered important, there have been few investigations of its effect. In the first half of this review, important traction methods are discussed, including traction direction. In second half, appropriate traction methods for each organ are considered. Other important considerations for traction method, such as ability to adjust traction strength, interference between traction device and endoscope, and the need for specialized devices are also discussed.

Advances in traction methods for endoscopic submucosal dissection: What is the best traction method and traction direction?

Endoscopic submucosal dissection (ESD) has been developed as a treatment for superficial gastrointestinal neoplasms, which can achieve en bloc resection regardless of the lesion size. However, ESD is technically difficult because endoscopists cannot bring their hand into the gastrointestinal tract, unlike surgeons in regular surgery. It is difficult to obtain sufficient tension in the dissection plane and a good field of vision. Therefore, ESD is associated with a long procedure time and a high risk of adverse events in comparison with endoscopic mucosal resection. Traction methods have been developed to provide sufficient tension for the dissection plane and a good field of vision during the ESD procedure. However, traction direction is limited in most traction methods, resulting in insufficient effect in some cases. Although traction direction is considered important, there have been few investigations of its effect. In the first half of this review, important traction methods are discussed, including traction direction. In second half, appropriate traction methods for each organ are considered. Other important considerations for traction method, such as ability to adjust traction strength, interference between traction device and endoscope, and the need for specialized devices are also discussed.

Effectiveness of S-O Clip-Assisted Colorectal Endoscopic Submucosal Dissection

This study aimed to assess the utility of the S-O clip during colorectal endoscopic submucosal dissection (ESD). We conducted a retrospective study on 185 patients who underwent colorectal ESD from January 2015 to January 2020. The patients were divided into two groups: before and after the introduction of the S-O clip. Forty-two patients underwent conventional ESD (CO group) and 29 patients underwent ESD using the S-O clip (SO group). We compared the surgery duration, dissection speed, en bloc resection rate, and complication rate between both groups. Compared with the CO group, the SO group had a significantly shorter surgery duration (70.7 ± 37.9 min vs. 51.2 ± 18.6 min; p = 0.017), a significantly higher dissection speed (15.1 ± 9.0 min vs. 26.3 ± 13.8 min; p < 0.001), a significantly higher en bloc resection rate (80.9% vs. 98.8%; p ≤ 0.001), and a significantly lower perforation rate (4.3% vs. 1.3%). In the right colon, the surgery duration was significantly shorter and the dissection speed was significantly higher in the SO group than in the CO group. Moreover, the rate of en bloc resection improved significantly in the right colon. S-O clip-assisted ESD reduces the procedure time and improves the treatment effects, especially in the right colon.

Comparison of the Effectiveness and Safety of Different Methods of Colorectal Endoscopic Submucosal Dissection: A Systematic Review and Network Meta-Analysis

BACKGROUND

Traditional endoscopic submucosal dissection (ESD) has developed different methods, such as pocket method (P-ESD), traction-assisted method (T-ESD), and hybrid method (H-ESD). In this meta-analysis, the benefits and drawbacks of different ESD methods were discussed and ranked.

STUDY DESIGN

Studies comparing different methods of colorectal ESD were searched by using PubMed, EMBASE, and Cochrane Library databases. The study was conducted for five endpoints: en bloc resection rate, R0 resection rate, operation time, dissection speed, and adverse events rate. Pairwise and network meta-analyses were performed through Rev Man 5.4 and Stata 16.0. The quality of all included studies was assessed using the Cochrane Risk of Bias Tool and the Newcastle-Ottawa Scale.

RESULTS

Twenty-six studies met the inclusion criteria, including 7 RCTs and 19 non-RCTs, with a total of 3,002 patients. The pooled analysis showed that the en bloc resection rate of H-ESD was significantly lower than that of C-ESD, P-ESD, and T-ESD (RR = 0.28, 95% CI [0.12, 0.65]; RR = 0.11, 95% CI [0.03, 0.44]; RR = 8.28, 95% CI [2.50, 27.42]). Compared with C-ESD, the operation time of H-ESD and T-ESD was significantly shorter (MD = -21.83, 95% CI [-34.76, -8.90]; MD = -23.8, 95% CI [-32.55, -15.06]). Meanwhile, the operation time of T-ESD was also significantly shorter than that of P-ESD (MD = -18.74, 95% CI [-31.93, -5.54]). The dissection speed of T-ESD was significantly faster than that of C-ESD (MD = 6.26, 95% CI [2.29, 10.23]).

CONCLUSION

P-ESD and T-ESD are probably the two best methods of colorectal ESD at present. The advantages of P-ESD are high en bloc resection rate and low incidence of adverse events. The advantages of T-ESD are rapid dissection and short operation time.

Effects of the combined use of a scissor-type knife and traction clip on endoscopic submucosal dissection of colorectal tumors: a propensity score-matched analysis

Background and study aims  This study evaluated the technical aspects of colorectal endoscopic submucosal dissection (ESD) with the Clutch Cutter (CC) (Fujifilm Co., Tokyo, Japan), a scissor-type knife, and the S-O clip (SO) as a traction clip, and compared the safety and efficacy to ESD using a needle-type knife. Patients and methods  This was a single-center retrospective study. In Study 1, we evaluated 125 ESD patients: 60 using the SO and CC (SO group) and 65 using the CC (CC group). In Study 2, we evaluated 185 ESD patients: the CC group (N = 65) and 120 using the Flush knife BT-S (Flush group) (Fujifilm Co., Tokyo, Japan). In both studies, the clinicopathological features and therapeutic outcomes were compared using a propensity score-matched analysis. Results  In 36 pairs of matched patients in Study 1, the rates of en bloc resection, R0 resection, perforation, and postoperative bleeding (POB) were 97.2 %, 88.9 %, 2.8 %, and 0 %, respectively, for the SO group and 100 %, 91.7 %, 0 %, and 0 % for the CC group (not significant). The mean procedure time for the SO group among less-experienced endoscopists was significantly shorter than in the CC group (42 vs. 65 minutes, P  = 0.036). In 49 pairs of matched patients in Study 2, the rates of en bloc resection, R0 resection, perforation, and POB were 100 %, 95.8 %, 0 %, and 0 %, respectively, for the CC group and 98.0 %, 95.8 %, 0 %, and 2.0 % for the Flush group (not significant). The mean procedure time in the CC group among less-experienced endoscopists was significantly shorter than in the Flush group (52 vs. 67 minutes, P  = 0.038). Conclusions  CC and the combined use of CC and SO reduced colorectal ESD procedure time among less-experienced endoscopists.

A retrospective cohort study of factors influencing long procedure times in colorectal endoscopic submucosal dissection

OBJECTIVE

To evaluate the outcomes and factors influencing colorectal endoscopic submucosal dissection (ESD) with a long procedure time.

MATERIALS AND METHODS

In this single-center, retrospective study, we included 1,100 patients with 1,199 lesions who underwent colorectal ESD between April 2016 and December 2020. ESD was performed using an advanced system knife for lesions >20 mm. An S-O clip was used as the traction device. The long-time group (LP; procedure time >120 min) and normal-time group (NP; procedure time <120 min) were compared.

RESULTS

The procedure times were 166.86 and 44.72 min in the LP and NP groups, respectively. The completion rate was higher in the NP group (96.5% vs. 83.5%, p = .001); the completed lesions were resected en bloc. Multivariate analysis revealed 18.8% and 7.8% of submucosal fibrosis in the LP and NP groups, respectively (odds ratio [OR] = 2.410, p = .026). Compared to the NP group, the LP group presented larger maximum lesion sizes and higher rates of R1 resection, and traction device use. Time to introduction of traction device use was longer in the LP than in the NP group (126.05 vs. 21.72 min; p < .001). Fibrosis tends to occur cecal lesions (OR 2.436, p = .011) and laterally spreading tumor-non-granular-pseudo-depressed (LST-NG-PD) (OR 2.6181, p = .001).

CONCLUSIONS

Lesion size and fibrosis were factors associated with a long procedure time in colonic ESD. For fibrotic lesions (LST-NG-PD and cecal lesions), it is necessary to consider early use of traction devices and advisable to plan a strategy for the use of traction devices.

Endoscopic instruments and techniques in endoscopic submucosal dissection for early gastric cancer

Introduction: Endoscopic submucosal dissection (ESD) is a less invasive local treatment for early gastric cancer (EGC).Areas covered: Japanese guidelines have recently expanded the endoscopic treatment indications for EGC. ESD is sometimes performed for lesions with a relative indication that has not previously been considered for ESD. ESD procedures are technically difficult, especially for larger and more invasive lesions. Complete resection and accurate histological assessment of EGC lesions are essential to evaluate endoscopic curability. Various endoscopic instruments, including three types of endoscopic knives and specific hemostatic forceps, have been developed, and endoscopic techniques, including the traction method, have been modified to simplify the procedure.Expert opinion: An insulated-tip knife with large tissue contact allows us to perform faster incisions, while a needle-type knife with minimal tissue contact allows us to perform precise incisions. Furthermore, a scissor-type knife with grasping tissues allows us to perform more secure incision. The traction method enables the operator to proceed with submucosal dissection procedures. In cases with small lesions, snaring can be used, as well as knife dissection. Understanding the features of each endoscopic instrument and technique is essential because appropriate selection and usage contribute to successful and safe ESD procedures.

Efficacy of Current Traction Techniques for Endoscopic Submucosal Dissection

This systematic review aimed to assess the efficacy of the current approach to tissue traction during the endoscopic submucosal dissection (ESD) of superficial esophageal cancer, early gastric cancer, and colorectal neoplasms. We performed a systematic electronic literature search of articles published in PubMed and selected comparative studies to investigate the treatment outcomes of tractionassisted versus conventional ESD. Using the keywords, we retrieved 381 articles, including five eligible articles on the esophagus, 13 on the stomach, and 12 on the colorectum. A total of seven randomized controlled trials and 23 retrospective studies were identified. Clip line traction and submucosal tunneling were effective in reducing the procedural time during esophageal ESD. The efficacy of traction methods in gastric ESD varied in terms of the devices and strategies used depending on the lesion location and degree of submucosal fibrosis. Several prospective and retrospective studies utilized traction devices without the need to reinsert the colonoscope. When pocket creation is included, the traction devices and methods effectively shorten the procedural time during colorectal ESD. Although the efficacy is dependent on the organ and tumor locations, several traction techniques have been demonstrated to be efficacious in facilitating ESD by maintaining satisfactory traction during dissection.

New Closure Method Using Loop and Open-Close Clips after Endoscopic Submucosal Dissection of Stomach and Colon Lesions

Endoscopic submucosal dissection (ESD) and en bloc resection of stomach and colon tumors have become common. However, mucosal defects resulting from ESD may cause delayed bleeding and perforation. To prevent adverse events, we developed a new clip closure technique, namely, the loop and open–close clip closure method (LOCCM), and aimed to examine its efficacy after ESD for stomach and colon tumors. The LOCCM uses loop and open–close clips. Here, the open–close clip was used to grasp the loop to bring it to the edge of the post-ESD mucosal defect. Another clip with a loop was then inserted into the opposite edge and clipped to the contralateral mucosa to pull both edges together. Once apposed, additional clips facilitated complete closure. The LOCCM was performed in 19 patients after ESD at Tottori University between October 2020 and March 2021. The outcomes retrospectively analyzed were the LOCCM success and adverse event rates. The complete closure rate using LOCCM was 89.5% and none of the patients had post-ESD bleeding or perforation. The results show that LOCCM is an effective and safe closure technique for mucosal defects after stomach and colon ESD to prevent bleeding and perforation.

Pocket Creation and Ring-thread Traction Facilitates Colorectal Endoscopic Submucosal Dissection for Non-experts

BACKGROUND/AIM

Colorectal endoscopic submucosal dissection (ESD) is a difficult technique. Counter-traction may facilitate the procedure but its efficacy in non-experts remains unclear. We determined the safety and efficacy of pocket creation and ring-thread traction (PRM) for non-expert colorectal ESD.

PATIENTS AND METHODS

We retrospectively compared patients who underwent conventional colorectal ESD (C-group, n=50) or PRM (pocket creation, whole-circumferential cutting, ring-thread traction, submucosal dissection; PRM-group, n=48). All procedures were performed by four non-experts, each with ≤40 experiences of colorectal ESD.

RESULTS

Procedural time was significantly shorter in the PRM-group compared with the C-group (p=0.007), with less additional device usage (p<0.001). There also tended to be fewer perforation incidents and muscle injuries in the PRM-group. There were no significant differences in en bloc or R0 resection rates between the groups.

CONCLUSION

PRM may be a safe, useful, and cost-effective technique for non-experts learning to perform colorectal ESD.

Prevention and Management of Complications and Education in Endoscopic Submucosal Dissection

Endoscopic submucosal dissection (ESD) is considered superior to endoscopic mucosal resection as an endoscopic resection because of its higher en bloc resection rate, but it is more difficult to perform. As ESD techniques have become more common, and the range of treatment by ESD has expanded, the number of possible complications has also increased, and endoscopists need to manage them. In this report, we will review the management of critical complications, such as hemorrhage, perforation, and stenosis, and we will also discuss educational methods for acquiring and improving ESD skills.

Comparing a conventional and a spring-and-loop with clip traction method of endoscopic submucosal dissection for superficial gastric neoplasms: a randomized controlled trial (with videos)

BACKGROUND AND AIMS

Several traction methods have sought to overcome the technical difficulties of endoscopic submucosal dissection (ESD). However, traction direction has remained limited in most of these methods, with lack of clarity about the optimal method and traction direction for gastric ESD. A spring-and-loop with clip (SLC) has been developed as a multidirectional traction device. Here, we investigated whether SLC traction-assisted ESD (SLC-ESD) improved procedure-related outcomes compared with conventional ESD (C-ESD) among patients with superficial gastric neoplasms.

METHODS

This single-center randomized controlled trial included patients with superficial gastric neoplasms undergoing SLC-ESD or C-ESD between October 2018 and December 2019. Using the multidirectional traction function, we set traction vertical to the gastric wall for SLC-ESD. The primary outcome was the median procedure time for gastric ESD.

RESULTS

The SLC-ESD and C-ESD groups comprised 40 patients each, and all the enrolled patients underwent the assigned treatment. The median ESD procedure time was significantly shorter in the SLC-ESD group (29.1 minutes) than in the C-ESD group (52.6 minutes; P = .005). SLC had a mean attachment time of 1.82 minutes. En bloc resection was achieved without perforation in all the patients in both groups.

CONCLUSIONS

Our findings suggest that SLC-ESD reduces gastric ESD procedure time without increasing the risk of perforation and that the vertical direction to the gastric wall is the appropriate traction direction for gastric ESD. (Clinical trial registration number: UMIN 000034533.).

Simplified magnetic anchor-guided endoscopic submucosal dissection: an ex vivo porcine model

INTRODUCTION AND AIMS

Endoscopic submucosal dissection (ESD) is a well-established treatment for superficial gastrointestinal tumors and enables en bloc resection. Adequate tissue tension is important for safe and effective dissection. Simplified magnetic anchor-guided ESD (MAG-ESD) with a neodymium magnet has potential benefits, compared with other current traction methods. We evaluated the feasibility of simplified MAG-ESD in an ex vivo porcine model.

MATERIALS AND METHODS

An experimental study was conducted, utilizing the standard ESD technique. An external magnet and an internal magnet, both neodymium magnets, were used for the magnetic anchoring. The internal magnet was attached to an arm of a hemoclip with a 2-0 silk suture. After the incision, the clip with the internal magnet was placed at the edge of the lesion. The external magnet was maneuvered around the surface to apply adequate tension.

RESULTS

A total of 15 en bloc ESDs (five with no magnetic anchoring and 10 with magnetic anchoring) were carried out. Traction and dissection were feasible in all cases and the procedures were completed in fewer than 90 min. Lesion size ranged from 15 to 50 mm (mean 30 mm). Two cases in the group with magnetic anchoring presented with punctate perforation (13.3%).

CONCLUSIONS

Our study demonstrated the feasibility of simplified MAG-ESD and en bloc resection in an ex vivo porcine model.

Double-clip traction could be superior to the pocket-creation method with cylindrical cap for colonic ESD: a randomized study in an ex vivo model

INTRODUCTION

In Western countries, debates between ESD vs piece-meal EMR as the best treatment for large colorectal adenomas persist regarding the difficulty of ESD the colon, and the safety and relatively good results of piece-meal endoscopic mucosal resection (EMR). Pocket-creation method (PCM) and double-clip countertraction (DCT) are two strategies recently published to facilitate ESD in this challenging situation.

METHOD

This is a randomized animal study to compare PCM and DCT strategies for colonic ESD on ex vivo models (bovine colon) performed by 3 operators novice in ESD. Hybridknife type T was used to inject normal saline tinted with a small amount of blue dye in all procedures. Randomization was stratified according to the use of gravity assist. Primary endpoint was the difference in resection speed between PCM and DCT strategies.

RESULTS

Resection speed was significantly higher in the DCT group than in the PCM group (56.3 vs. 31.6 mm²/min, p = 0.01). Technical success rate, defined as en bloc resection in under 60 min, was significantly better in the DCT group than in the PCM group (100% vs. 84.4%, p = 0.024), perforation rate was lower (0% vs. 18.8%, p = 0.012), and difficulty score was better (2.4 vs. 6.2, p < 0.0001) as was procedure duration (24.2 vs. 40.2 min, p < 0.0001).

CONCLUSION

DCT was superior to PCM for ESD in our validated bovine colon model. This strategy is inexpensive, easy to use and adaptive. It might facilitate the widespread use of colonic ESD in Western countries and change Western ideas regarding the use of colonic ESD compared with piece-meal EMR for large benign lesions.

ESD and Pit Pattern Diagnosis: Lessons from a Japanese Endoscopist Working in the United States

Endoscopic submucosal dissection (ESD) was developed in 2000s to overcome the limitations of endoscopic mucosal resection (EMR), especially to accomplish en-bloc resection, and it has been accepted worldwide in the past decades. Many ESD devices and diagnosis modalities are currently available, which include pit pattern and narrow band imaging (NBI) diagnoses to evaluate the depth of the tumor preoperatively with sensitivities of 70 to 90%. Depending on the Japanese colorectal guideline, the intramucosal cancer and shallow invasion of the submucosal layer are the main good indications of ESD; however, the ESD practices between Japan and Western countries still vary, including pathologic definition of cancer, tumor/node/metastasis classification, and handling of ESD specimen. In the United States, despite the large demand for treatment of colorectal neoplasm, pit pattern and magnified NBI diagnoses are not widely accepted yet, and piecemeal EMR is still the major method in most of the institutions. Moreover, the specific guideline of ESD is also not available yet. More new technologies are being developed other than conventional ESD methods in Eastern and Western countries, and ESD is now expected to change in the next generation. It is recommended that not only gastroenterologists but also colorectal surgeons have appropriate knowledge of colorectal lesions and their management to ensure current treatments is applied to patients.

Internal traction method using a spring-and-loop with clip (S-O clip) allows countertraction in gastric endoscopic submucosal dissection

BACKGROUND

Insufficient countertraction and poor field of vision make endoscopic submucosal dissection (ESD) difficult. Internal traction method using a spring-and-loop with clip (SLC) allows sufficient traction in any direction and good field of vision. However, the attachment procedure is difficult and interference with the endoscope can occur in the retroflexed endoscopic position. We have developed a new use of SLC that simplifies the attachment procedure, eliminating interference with the endoscope. The aim of this study was to investigate the efficacy of SLC for gastric ESD.

METHODS

We retrospectively recruited 140 patients with gastric neoplasms who underwent ESD between November 2015 and October 2018 at our department. Among them, 51 patients treated using SLC-assisted ESD (SLC-ESD) and 89 patients treated using conventional ESD (C-ESD) were compared. Propensity score matching was performed to compensate for the differences in age, sex, lesion location, lesion position, specimen size, and ulcer findings. The primary outcome was ESD procedure time.

RESULTS

Propensity score matching generated 51 matched pairs. The procedure time in the SLC-ESD group was significantly shorter than that in the C-ESD group (median [interquartile], 40.0 [27.0-81.5] minutes versus 69.0 [46.5-113.5] minutes, P = 0.008). The mean SLC attachment time was 2.08 min. There were no significant differences in complete en bloc resection rate between SLC-ESD and C-ESD groups (100% versus 96.1%, P = 0.495). There were not perforation cases in either group.

CONCLUSIONS

SLC may offer an efficient method for gastric ESD, with a short attachment procedure time.

Bipolar-current needle-knife with a water jet function (Jet B-knife) shortens the procedure time of endoscopic submucosal dissection for colorectal tumors

BACKGROUND

Endoscopic submucosal dissection (ESD) is a technically difficult and time-consuming procedure for the treatment of large colorectal tumors. In Japan, the ball-tip bipolar-current needle-knife (BB-knife) has been used in ESD as a safe device that minimizes the damage to deeper tissues of colorectal neoplasms. In May 2012, a BB-knife combined with a water jet function (Jet B-knife) was newly developed.

METHODS

This retrospective study was aimed at examining the effectiveness and safety of the Jet B-knife. The BB-knife was used in 276 lesions (BB-knife group), while the Jet B-knife was used in 245 lesions (Jet B-knife group). We evaluated tumor characteristics and the results of the ESD procedures, including the size of the resected tumor, histological diagnosis, time required for resection, frequency of using other electrical devices, en bloc resection rate, and incidence rate of associated complications. Then, the data obtained were compared between the two groups.

RESULTS

The histological evaluation of the resected tumors revealed that the incidence of cancer was not significantly different between the two groups. The median time required for resection was 103 min (45-255) in the BB-knife group and 51 min (28-210) in the Jet B-knife group. The difference was statistically significant (p < 0.05). Furthermore, the median tumor diameters were 23.1 mm (18-50) and 26.2 mm (20-60) in the BB-knife and Jet B-knife groups, respectively, demonstrating a statistically significant difference (p < 0.05). Multivariate logistic regression analysis revealed that short resection time (p < 0.001) and reduced use of hemostatic devices (p < 0.01) were independent favorable features of Jet B-knife. The en bloc resection rate and the perforation rate were not statistically significant between the two groups.

CONCLUSIONS

Use of the Jet B-knife may contribute to the development of a time-saving, cost-effective, and safe procedure for ESD of colorectal tumors.

Clinical utility of the pocket-creation method with a traction device for colorectal endoscopic submucosal dissection

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) is technically demanding while ensuring safety, especially in cases with fibrosis and/or poor maneuverability. To overcome such difficulties, we developed a novel method called the pocket-creation method with a traction device (PCM with TD). We then evaluated the effectiveness and safety of PCM with TD in colorectal ESD compared to other conventional methods.

METHODS

In total, 324 colorectal lesions treated with ESD from July 2018 to June 2019 were included. The following three treatment strategies were used: conventional ESD (CE), CE with TD, and PCM with TD. Patient backgrounds and treatment outcomes were retrospectively compared and analyzed.

RESULTS

As ESD methods, CE, CE with TD, and PCM with TD account for 58% (187/324), 24% (78/324), and 18% (59/324), respectively. No significant difference was observed among the three groups in en bloc and R0 resection rates or adverse events. The rate of lesions with fibrosis and poor maneuverability was significantly higher in the PCM with TD group (CE group vs CE with TD group vs PCM with TD group: fibrosis, 24% vs 47% vs 64%, p < 0.001; poor maneuverability, 5.3% vs 13% vs 20%, p = 0.002). Dissection speed was significantly higher in the PCM with TD than in the CE with TD group (p = 0.003).

CONCLUSIONS

PCM with TD can achieve a stable en bloc resection rate and R0 dissection rate without adverse events even in the hands of trainees, irrespective of the size and location of the lesion, presence of fibrosis, and under poor maneuverability conditions.

Review on colorectal endoscopic submucosal dissection focusing on the technical aspect

BACKGROUND

Endoscopic submucosal dissection (ESD) enables removal of broad-based colorectal polyps or lateral spreading tumors with a higher rate of en bloc resection and a lower risk of local recurrence. However, it is technically demanding. Over the past 20 years, various equipment and innovative techniques have been developed to reduce the difficulty of ESD. The information in the literature is scattered. Our aim is to provide a comprehensive review on the setup and technical aspects of colorectal ESD.

METHODS

We searched the PubMed database and systemically reviewed all original and review articles related to colorectal ESD. Further manual search according to reference lists of identified articles were done. The selected articles were categorized and reviewed. Original figures were created to help readers understand some of the ESD techniques.

RESULTS

A total of 216 articles were identified, in which 25 of them were review articles and 191 of them were original articles. They were categorized and reviewed. An in-depth appraisal of the setting, equipment, and technical aspects of colorectal ESD was performed.

CONCLUSIONS

Although ESD is a technically demanding procedure that requires expert endoscopic skills, it can be mastered. With good peri-procedural preparation, sufficient knowledge of the equipment, and thorough understanding of the useful endoscopic tricks and maneuvers, colorectal ESD can be performed smoothly and safely.

Evaluation of a robotic arm-assisted endoscope to facilitate endoscopic submucosal dissection (with video)

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is considered technically difficult and challenging using a conventional flexible endoscope, mainly due to the lack of proper countertraction to expose the submucosal dissection plane. This study aimed to evaluate the feasibility of a traction method using a dexterous robotic arm in ex vivo gastric ESD.

METHODS

ESD was performed in a total of 45 procedures using a portable endoscopic tool handler (PETH) (n = 30) and using the conventional method (n = 15) at various locations in the stomach. For each procedure, the performance data were recorded, including the total procedure time (minutes), incision time (minutes), dissection speed (mm²/minute), and blind dissection rate (%), to enable a comparison of the 2 ESD methods.

RESULTS

The total procedure time was significantly shorter with PETH-ESD than in conventional ESD (23 vs 36 minutes, P = .011). This result is mainly attributed to the dissection speed, which was significantly faster, by more than 2.5 times, using the PETH (122.3 ± 76.5 vs 47.5 ± 26.9 mm²/minute, P < .001). The blind dissection rate was greatly decreased in PETH-ESD (0 vs 20%, P < .001). There was no significant difference in the incision time (6.1 ± 5.0 vs 5.5 ± 2.9 min, P = .612).

CONCLUSIONS

The countertraction method using the PETH significantly improved the dissection speed and reduced blind dissection by enhancing direct visualization of the submucosal plane. With the advantages of multidirectional traction, fine tension control, and regrasping, this new device is expected to improve the performance of ESD and further facilitate advanced endoscopic procedures.