Debates on colorectal endoscopic submucosal dissection - traction for effective dissection: gravity is enough

Efficacy and safety of multi-loop traction device-assisted colorectal endoscopic submucosal dissection: Multicenter randomized clinical trial

Background and study aims

The multi-loop traction device (MLTD) facilitates optimal visualization of the submucosa throughout endoscopic submucosal dissection (ESD). This trial aimed to assess the efficacy of MLTD for colorectal ESD.

Patients and methods

We conducted a multicenter, open-label, randomized controlled trial involving patients with colorectal lesions ≥ 20 mm suspicious for noninvasive carcinoma. Participants were randomly assigned in a 1:1 ratio to undergo ESD with MLTD (MLTD-ESD group) or ESD without any traction device (control group). Endoscopists were allowed to convert treatments if dissection became challenging for 10 minutes. The primary endpoint was dissection speed; secondary endpoints included technical success rate and adverse events (AEs).

Results

A total of 108 participants were randomized to the MLTD-ESD group (n = 53) and the control group (n = 55). There was no statistically significant difference in median dissection speed between the MLTD-ESD group and the control group (14.8 mm 2 /min; interquartile range [IQR] 8.9-23.9 mm 2 /min vs. 13.3 mm 2 /min; IQR 8.9-18.8 mm 2 /min) ( P = 0.33). The technical success rate was significantly higher in the MLTD-ESD group (96.2%) compared with the control group (71.0%) ( P < 0.0001). All technical failures were due to treatment conversions. No significant difference was observed in AEs. Subgroup analysis revealed that experts in the MLTD-ESD group had faster dissection speed than controls (21.6 mm2/min; IQR 15.5-28.8 mm 2 /min vs. 14.4 mm 2 /min; IQR 9.9-21.2 mm 2 /min) ( P = 0.009).

Conclusions

This multicenter randomized trial demonstrated that use of MLTD did not significantly increase dissection speed for colorectal ESD. Treatment conversions may have influenced the primary endpoint, and further investigation is warranted.

Conventional Versus Traction Endoscopic Submucosal Dissection for Colorectal Tumors: A Meta-analysis of Randomized Controlled Trials

INTRODUCTION

Compared with conventional endoscopic submucosal dissection (C-ESD) for colorectal lesions, the traction method (T-ESD) allows the lesion to be stabilized with easier dissection. However, randomized controlled trials (RCTs) have reported conflicting results on the clinical outcomes of T-ESD as compared with C-ESD. We conducted a meta-analysis to compile the data.

METHODS

Multiple databases were searched for RCTs evaluating C-ESD versus T-ESD for colorectal tumors. The end points of interest were procedure time (min), resection speed (mm²/min), R0 resection, en bloc resection, delayed bleeding, and perforation. Standard meta-analysis methods were employed using the random-effects model.

RESULTS

Six RCTs with a total of 566 patients (C-ESD n=284, T-ESD n=282) were included. The mean age was 67±10 y and 60% were men. As compared with the T-ESD technique, the C-ESD group was associated with longer procedure time (SMD 0.91, 95% CI 0.58 to 1.23, P <0.00001) and lesser resection speed (SMD -1.03, 95% CI -2.01 to -0.06, P =0.04). No significant difference was found in the 2 groups with respect to R0 resection rate (RR 1.00, 95% CI 0.94 to 1.06, P =0.87), en bloc resection (RR 0.99, 95% CI 0.97 to 1.01, P =0.35), delayed bleeding (RR 0.66, 95% CI 0.17 to 2.59, P =0.55) and perforation (RR 2.16, 95% CI 0.75 to 6.27, P =0.16).

DISCUSSION

On meta-analysis, pooled procedure time was significantly faster with T-ESD compared with C-ESD. The clinical outcomes, however, were comparable.

Transanal Minimally Invasive Surgery Versus Endoscopic Submucosal Dissection for Rectal Lesions: A Community Hospital Experience

Background: To compare tumor margins and surgical outcomes between transanal minimally invasive surgery (TAMIS) and endoscopic submucosal dissection (ESD) for large or malignant rectal adenomatous polyps. Methods: Single institution retrospective analysis of patients who underwent TAMIS or ESD surgery. Results: In total, 30 consecutive patients with similar demographics who underwent either TAMIS (n = 19) or ESD (n = 11) were included. The median (interquartile range, IQR) tumor distances from the anal verge for TAMIS and ESD were 5 cm (3.5-8) and 3 cm (2-4.25) (P = 0.016). Four in TAMIS and two in ESD occupied more than half of the circumference of the bowel lumen. Five (four in situ and one stage 1) in TAMIS and two (one in situ and one stage 1) in ESD were malignant. The median specimen length, width, and height were 3.2 cm, 2.6 cm, and 1.0 cm and 3.5 cm, 2.0 cm, and 0.3 cm for TAMIS and ESD, respectively. There were no statistically significant differences in tumor circumference, malignant ratios, or specimen sizes. Resection margins were involved in two of the ESD, while none of the TAMIS were involved (P = 0.041). The median (IQR) operative time was 72 (62-89) minutes and 120 (90-180) minutes for TAMIS and ESD (P = 0.005). The median (IQR) follow-up time was 3.3 (0.3-11.7) and 0.9 (0.3-15.4) months for TAMIS and ESD. There were no morbidities, no mortalities, or local recurrences among the two groups. Conclusions: Both TAMIS and ESD were found to be feasible and safe in community hospital practice. Operative time was shorter, and there were no involved margins in TAMIS (versus ESD).

Experimental study of magnetic hydrogel assisted magnetic anchorguided endoscopic submucosal dissection in colonic tumors

BACKGROUND

Endoscopic submucosal dissection (ESD) is a well-established treatment for gastrointestinal tumors and enables en bloc resection. Adequate counter traction with good visualization is important for safe and effective dissection.

OBJECTIVE

Based on magnetic anchor-guided endoscopic submucosal dissection (MAG-ESD), we would like to explore the feasibility of magnetic hydrogel as an internal magnetic anchor that can be injected into the submucosa through an endoscopic needle to assist colonic endoscopic submucosal dissection.

METHODS

This prospective trial was conducted on 20 porcine colons ex vivo. We injected magnetic hydrogel into submucosa of the porcine colons ex vivo for MAG-ESD to evaluate the traction effect and operation satisfaction.

RESULTS

Magnetic hydrogel assisted ESD was successfully performed on 20 porcine colons ex vivo. Adequate counter traction with good visualization was successfully obtained during the procedure of dissection.

CONCLUSION

Magnetic hydrogel assisted MAG-ESD is feasible and effective.

ESD with elastic ring traction is more effective and safer than conventional ESD in large proximal colon neoplastic lesions: a retrospective cohort study (with video)

BACKGROUND AND AIMS

Colorectal endoscopic submucosal resection (ESD), especially ESD in proximal colon, has always been challenging. We invented a novel elastic ring as a traction method to facilitate ESD. Our study aims to compare the safety and effectiveness of ESD with in vivo traction and conventional ESD without traction in the treatment of large proximal colon neoplastic lesions.

METHODS

This retrospective cohort study included consecutive patients with large (≥ 20 mm in their maximal diameter) proximal colon neoplastic lesions who underwent ESD with in vivo elastic ring traction or conventional ESD without traction in our endoscopy center between June 2018 and April 2022 by one experienced endoscopist.

RESULTS

The ESD with traction group has lower overall complication rate and lower perforation rate than those in the conventional ESD group (0% vs 14.71%, P = 0.021; 0% vs 11.76%, P = 0.048, respectively), and the differences are statistically significant. Although there are no significant differences in the rates of en bloc resection and R0 resection and bleeding rate, ESD with traction group still had higher en bloc resection and R0 resection rates and lower bleeding rate than conventional ESD group without traction (100% vs 94.12%, P = 0.226; 94.59% vs 85.29%, P = 0.189, 8.82% vs 2.70%, P = 0.276, respectively).

CONCLUSION

ESD with elastic ring traction is potentially more effective and safer than conventional ESD in the treatment of large proximal colon neoplastic lesions. Further large, prospective controlled studies are needed to fully evaluate this novel method.

Magnetic anchor technique assisted endoscopic submucosal dissection for early esophageal cancer

BACKGROUND

Esophageal cancer has high incidence globally and is often diagnosed at an advanced stage. With the widespread application of endoscopic technologies, the need for early detection and diagnosis of esophageal cancer has gradually been realized. Endoscopic submucosal dissection (ESD) has become the standard of care for managing early tumors of the esophagus, stomach, and colon. However, due to the steep learning curve, difficult operation, and technically demanding nature of the procedure, ESD has currently been committed to the development of various assistive technologies.

AIM

To explore the feasibility and applicability of magnetic anchor technique (MAT)-assisted ESD for early esophageal cancer.

METHODS

Isolated pig esophagi were used as the experimental model, and the magnetic anchor device was designed by us. The esophagi used were divided into two groups, namely the operational and control groups, and 10 endoscopists completed the procedure. The two groups were evaluated for the following aspects: The total operative time, perforation rate, rate of whole mucosal resection, diameter of the peering mucosa, and scores of endoscopists' feelings with the procedure, including the convenience, mucosal surface exposure degree, and tissue tension. In addition, in the operational group, the soft tissue clip and the target magnet (TM) were connected by a thin wire through a small hole at the tail end of the TM. Under gastroscopic guidance, the soft tissue clip was clamped to the edge of the lesioned mucosa, which was marked in advance. By changing the position of the anchor magnet (AM) outside the esophagus, the pulling force and pulling direction of the TM could be changed, thus exposing the mucosal peeling surface and assisting the ESD.

RESULTS

Herein, each of the two groups comprised 10 isolated esophageal putative mucosal lesions. The diameter of the peering mucosa did not significantly differ between the two groups (2.13 ± 0.06 vs 2.15 ± 0.06, P = 0.882). The total operative time was shorter in the operational group than in the control group (17.04 ± 0.22 min vs 21.94 ± 0.23 min, P < 0.001). During the entire experiment, the TM remained firmly connected with the soft tissue clip and did not affect the opening, closing, and release of the soft tissue clip. The interaction between the TM and AM could provide sufficient tissue tension and completely expose the mucosa, which greatly assists the surgeon with the operation. There was no avulsion of the mucosa, and mucosal lesions were intact when peeled. Therefore, the scores of endoscopists' feelings were higher in the operational group than in the control group in terms of the convenience (9.22 ± 0.19 vs 8.34 ± 0.15, P = 0.002), mucosal surface exposure degree (9.11 ± 0.15 vs 8.25 ± 0.12, P < 0.001), and tissue tension (9.35 ± 0.13 vs 8.02 ± 0.17, P < 0.001). The two groups did not significantly differ in the perforation rate and rate of whole mucosal resection.

CONCLUSION

We found MAT-assisted ESD safe and feasible for early esophageal cancer. It could greatly improve the endoscopic operation experience and showed good clinical application prospects.

Comparison Between Preincision Traction and On-Demand Traction in Assisting Colorectal Endoscopic Submucosal Dissection

INTRODUCTION

Adequate exposure of the dissection site is very important for colorectal endoscopic submucosal dissection (ESD). We aimed to investigate the safety and efficacy of the preincision traction (PIT) method using an internal clip-with-spring device in comparison with the conventional on-demand traction (ODT) method in assisting colorectal ESD.

METHODS

This was a prospective nested case-control study. A total of 26 patients for PIT-ESD and other 26 patients for ODT-ESD were involved. Data on clinical characteristics and therapeutic outcomes were collected and analyzed.

RESULTS

The en bloc resection rate (both 100%) and curative resection rate (92.3% vs 96.2%) showed no significant difference between the 2 groups. Compared with ODT-ESD, PIT-ESD significantly reduced the procedure time (29.8 ± 18.4 vs 57.4 ± 33.7 minutes, P = 0.001) and submucosal injection volume (49.6 ± 32.3 vs 70.8 ± 37.6 mL, P = 0.034), decreased the rate of intraoperative bleeding (26.9% vs 57.7%, P = 0.025) and muscular injury (7.7% vs 34.6%, P = 0.038), and shortened the postoperative hospital stay (1.8 ± 0.8 vs 2.5 ± 1.2, P = 0.015).

DISCUSSION

The PIT method could significantly improve the safety and efficacy of colorectal ESD.

Eine neue Traktionsvorrichtung (S-O-Clip) zur Erleichterung der endoskopischen Submukosa-Dissektion von Tumoren im Bereich der Ileozökalklappe

BACKGROUND

Endoscopic submucosal dissection (ESD) is a method that can be used for en bloc resection, regardless of the size and form of the lesion. The special location of ileocecal tumors leads to insufficient counter-traction and poor field of vision, making ESD difficult. An S-O clip has been developed to simplify the attachment procedure, eliminating interference with the endoscope and improving accessibility.

CASE PRESENTATION

The patient was a 70-year-old man who presented with abdominal pain and bloating. A colonoscopy revealed a flat-elevated-type lesion on the ileocecal valve, with the oral side of the lesion having progressed to the terminal ileum. The traction direction was adjusted from distal to proximal during the procedure using the S-O clip. Finally, with the help of the S-O clip, the tumor was safely removed and collected.

CONCLUSION

The S-O clip was successful in ESD of a colorectal tumor. By removing and re-anchoring the loaded ring, the S-O clips allowed the adjustment of traction direction from distal to proximal during ESD.

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.

A novel flexible auxiliary single-arm transluminal endoscopic robot facilitates endoscopic submucosal dissection of gastric lesions (with video)

BACKGROUND

Using conventional endoscope to perform endoscopic submucosal dissection (ESD) is difficult because of the one-handed operation and blind dissection caused by gravity. Poor visualization of the submucosal plane causes ESD to be associated with a high risk of bleeding and perforation. This study aimed to develop a novel ESD-assistive robot system and to evaluate its efficacy.

METHODS

A novel flexible auxiliary single-arm transluminal endoscopic robot (FASTER) was developed. A total of 36 artificial lesions in ex vivo porcine stomachs were removed using the FASTER-assisted ESD method (n = 18) and the conventional ESD method (n = 18). Lesions were 2 cm or 4 cm in diameter, located on the anterior and posterior walls of the antrum. Primary outcome measurements were dissection time and dissection speed.

RESULTS

The dissection time in FASTER-assisted ESD was significantly shorter than that in conventional ESD (7 min vs 13 min, p = 0.012), mainly because of the faster dissection speed (148.6 vs 97.0 mm²/min, p = 0.002). The total procedure time in FASTER-assisted ESD was shorter than that in conventional ESD, but the difference was not significant (16 min vs 24 min, p = 0.252). Complete en bloc resection was achieved in all lesions. No perforations were detected. The FASTER exhibited the ability of regrasp, multidirectional traction, and proper tension control during ESD.

CONCLUSION

FASTER significantly increased the dissection speed by providing proper traction and achieving good submucosal vision. This new device is expected to facilitate ESD in clinical practice.

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.

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.

Endoscopic resection of large (≥ 4 cm) upper gastrointestinal subepithelial tumors originating from the muscularis propria layer: a single-center study of 101 cases (with video)

BACKGROUND AND AIMS

Although endoscopic resection (ER) is already established as a minimally invasive technique for small (< 4.0 cm) upper gastrointestinal subepithelial tumors originating from the muscularis propria layer (MP-SETs), published data of ER for large (≥ 4.0 cm) upper gastrointestinal MP-SETs are extremely rare and limited to case reports. This retrospective study aimed to evaluate the feasibility and safety of ER for large (≥ 4.0 cm) upper gastrointestinal MP-SETs in a large case series.

METHODS

Between June 2012 and December 2018, 101 patients with large (≥ 4 cm) upper gastrointestinal MP-SETs were enrolled in this study. The main outcome measures included complete resection, total complications, and local residual or recurrent tumor.

RESULTS

The rate of complete resection was 86.1%. Thirteen patients (12.9%) experienced complications including gas-related complications (6/101, 5.9%), localized peritonitis (4/101, 4.0%), esophageal/cardiac mucosal laceration (2/101, 2.0%), and delayed bleeding (1/101, 1.0%). These 13 patients recovered after endoscopic and conservative treatment. The independent risk factor for incomplete resection was tumor size (P = 0.005), and the independent risk factors for total complications were tumor size (P = 0.011) and tumor extraluminal growth (P = 0.037). During the median follow-up of 36 months, local residual tumor was detected in 1 patient. No local recurrence occurred in any patient.

CONCLUSIONS

Despite being associated with a relatively low complete resection rate, ER is an alternative therapeutic method for large (≥ 4.0 cm) upper gastrointestinal MP-SETs when performed by an experienced endoscopist. This method is especially valuable for patients who are unwilling to undergo surgery.

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.

Clinical usefulness of the S-O clip during colorectal endoscopic submucosal dissection in difficult-to-access submucosal layer

Background and study aims  In colorectal endoscopic submucosal dissection (ESD), the S-O clip improves the accessibility to the submucosal layer of the colon. However, its safety and usefulness in difficult colorectal ESDs are unclear. Thus, in this study, we aimed to assess the effectiveness of the S-O clip in colorectal ESD in the difficult-to-access submucosal layer. Patients and methods  From January 2016 to December 2016, 189 consecutive cases of colorectal ESD were performed at Hiroshima University Hospital before the S-O clip was introduced. Between January 2017 and June 2018, among 271 consecutive colorectal ESD cases, 41 cases were performed colorectal ESD using the S-O clip. We compared outcomes between the two groups (41 cases with S-O clip [use group] and 189 cases without S-O clip [non-use group]) using propensity score matching. Results  Prior to propensity score matching, 41 cases with the S-O clip (use group) and 189 cases without the S-O clip (non-use group) were extracted. The degree of submucosal fibrosis was more severe and the procedure time was longer in the use group than in the non-use group. In the use and non-use groups, en bloc resection (100 % vs. 94.7 %) and complete en bloc resection (100 % vs. 92.6 %) rates were satisfactory. After propensity score matching, 33 cases in each group were extracted. As a result, complete en bloc resection rate was significantly higher in the use group than in the non-use group (100 % vs. 84.9 %). Conclusion  The S-O clip is effective and can be used safely in colorectal ESD in the difficult-to-access submucosal layer.

Magnetic bead-assisted endoscopic submucosal dissection: a gravity-based traction method for treating large superficial colorectal tumors

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) has always been challenging for endoscopists, but the procedure can be facilitated after adequate exposure of submucosal layer and cutting line. We developed a traction method based on gravity for facilitating colorectal ESD, referred as magnetic bead-assisted ESD (MBA-ESD). This study aimed to compare the safety and effectiveness of MBA-ESD and conventional ESD for treating large superficial colorectal tumors.

METHODS

This retrospective study included consecutive patients with large (≥ 20 mm in their maximal diameter) superficial colorectal tumors who underwent MBA-ESD or conventional ESD at our endoscopy center between June 2017 to January 2018. Each patient in the MBA-ESD group was matched to a patient in the conventional ESD group using propensity scores.

RESULTS

Thirteen patients in each group were matched for the analyses. The baseline characteristics were balanced after propensity matching. The incidence of overall complications was significantly lower in the matched MBA-ESD group (0% vs. 38.5%, P = 0.039), while similar rates of en bloc resection, R0 resection, curative resection, and tumor recurrence were noted. Although without statistic difference, dissection time and speed were improved when using MBA-ESD (33 min vs. 40 min, P = 0.111; and 21 mm2/min vs. 16 mm2/min, P = 0.143, respectively).

CONCLUSIONS

MBA-ESD is a feasible, safe, and effective method for treating large superficial colorectal tumors. Further large, prospective and controlled studies are needed to fully assess this method.

Efficacy of traction-assisted colorectal endoscopic submucosal dissection using a clip-and-thread technique: A prospective randomized study

BACKGROUND AND AIM

Colorectal endoscopic submucosal dissection (ESD) remains challenging because of technical difficulties, long procedure time, and high risk of adverse events. To facilitate colorectal ESD, we developed traction-assisted colorectal ESD using a clip and thread (TAC-ESD) and conducted a randomized controlled trial to evaluate its efficacy.

METHODS

Patients with superficial colorectal neoplasms (SCN) ≥20 mm were enrolled and randomly assigned to the conventional-ESD group or to the TAC-ESD group. SCN ≤50 mm were treated by two intermediates, and SCN >50 mm were treated by two experts. Primary endpoint was procedure time. Secondary endpoints were TAC-ESD success rate (sustained application of the clip and thread until the end of the procedure), self-completion rate by the intermediates, and adverse events.

RESULTS

Altogether, 42 SCN were analyzed in each ESD group (conventional and TAC). Procedure time (median [range]) for the TAC-ESD group was significantly shorter than that for the conventional-ESD group (40 [11-86] min vs 70 [30-180] min, respectively; P < 0.0001). Success rate of TAC-ESD was 95% (40/42). The intermediates' self-completion rate was significantly higher for the TAC-ESD group than for the conventional-ESD group (100% [39/39] vs 90% [36/40], respectively; P = 0.04). Adverse events included one intraoperative perforation in the conventional-ESD group and one delayed perforation in the TAC-ESD group.

CONCLUSION

Traction-assisted colorectal endoscopic submucosal dissection reduced the procedure time and increased the self-completion rate by the intermediates (UMIN000018612).

Magnetic anchor guidance for endoscopic submucosal dissection and other endoscopic procedures

Endoscopic submucosal dissection (ESD) is a well-established, minimally invasive treatment for superficial neoplasms of the gastrointestinal tract. The universal adoption of ESD has been limited by its slow learning curve, long procedure times, and high risk of complications. One technical challenge is the lack of a second hand that can provide traction, as in conventional surgery. Reliable tissue retraction that exposes the submucosal plane of dissection would allow for safer and more efficient dissection. Magnetic anchor guided endoscopic submucosal dissection (MAG-ESD) has potential benefits compared to other current traction methods. MAG-ESD offers dynamic tissue retraction independent of the endoscope mimicking a surgeon's "second hand". Two types of magnets can be used: electromagnets and permanent magnets. In this article we review the MAG-ESD technology, published work and studies of magnets in ESD. We also review the use of magnetic anchor guidance systems in natural orifice transluminal endoscopic surgery and the idea of magnetic non-contact retraction using surface ferromagentization. We discuss the current limitations, the future potential of MAG-ESD and the developments needed for adoption of this technology.

Colorectal endoscopic submucosal dissection from a Western perspective: Today’s promises and future challenges

Over the last few years, endoscopic submucosal dissection (ESD) has shown to be effective in the management of early colorectal neoplasms, particularly in Asian countries where the technique was born. In the Western world, its implementation has been slow and laborious. In this paper, the indications for ESD, its learning model, the available methods to predict the presence of deep submucosal invasion before the procedure and the published outcomes from Asia and Europe will be reviewed. Since ESD has several limitations in terms of learning achievement in the West, and completion of the procedure for the first cases is difficult in our part of the world, a short review on colorectal assisted ESD has been included. Finally, other endoscopic and surgical treatment modalities that are in competition with colorectal ESD will be summarized.

Prospective randomized comparison of endoscopic submucosal tunnel dissection and conventional submucosal dissection in the resection of superficial esophageal/gastric lesions in a living porcine model

BACKGROUND AND STUDY AIMS

To assess experimentally endoscopic submucosal tunnel dissection (ESTD) as an alternative technique of endoscopic submucosal resection.

PATIENTS AND METHODS

This was a prospective, randomized, comparative experimental animal study carried out over a period of 9 months at the surgical research and teaching center of Aix-Marseille University, France. Virtual esophageal and gastric lesions measuring 3 cm in diameter were resected in pigs weighing 25 to 30 kg. The primary aim was to evaluate ESTD's efficacy compared with endoscopic submucosal dissection (ESD). The secondary aims were to determine complication rates as well as to assess procedure time and procedure speed, histologic quality of the resected specimen, and procedure cost.

RESULTS

Eighteen procedures (9 ESD and 9 ESTD) were performed in nine pigs. The technical success rate was 88.9 % for both techniques, with one single failure in each. The en bloc resection rate was 100 % for ESTD and 88.9 % for ESD (one failure). The complication rate (22 %) and median procedure time were similar but dissection speed was quicker with ESTD in the esophagus (P = 0.03). Median procedure cost (728 Euros for ESD and ESTD) did not differ. On histologic examination, the lateral margins were healthy in 100 % of ESTD and in 88.9 % of ESD (P = 0.49). Deep resection margins were of better quality in ESTD (median submucosal thickness: 1307.1 µm vs. 884.7 µm; P = 0.039).

CONCLUSIONS

ESTD is feasible and safe but not superior in the treatment of superficial esophageal/gastric lesions in porcine models compared with ESD. Nevertheless it provides a better quality histologic specimen.

Colorectal endoscopic submucosal dissection: Recent technical advances for safe and successful procedures

Endoscopic submucosal dissection (ESD) is very useful in en bloc resection of large superficial colorectal tumors but is a technically difficult procedure because the colonic wall is thin and endoscopic maneuverability is poor because of colonic flexure and extensibility. A high risk of perforation has been reported in colorectal ESD. To prevent complications such as perforation and unexpected bleeding, it is crucial to ensure good visualization of the submucosal layer by creating a mucosal flap, which is an exfoliated mucosa for inserting the tip of the endoscope under it. The creation of a mucosal flap is often technically difficult; however, various types of equipment, appropriate strategy, and novel procedures including our clip-flap method, appear to facilitate mucosal flap creation, improving the safety and success rate of ESD. Favorable treatment outcomes with colorectal ESD have already been reported in many advanced institutions, and appropriate understanding of techniques and development of training systems are required for world-wide standardization of colorectal ESD. Here, we describe recent technical advances for safe and successful colorectal ESD.

Advanced endoscopic submucosal dissection with traction

Endoscopic submucosal dissection (ESD) has been established as a standard treatment for early stage gastric cancer (EGC) in Japan and has spread worldwide. ESD has been used not only for EGC but also for early esophageal and colonic cancers. However, ESD is associated with several adverse events, such as bleeding and perforation, which requires more skill. Adequate tissue tension and clear visibility of the tissue to be dissected are important for effective and safe dissection. Many ESD methods using traction have been developed, such as clip-with-line method, percutaneous traction method, sinker-assisted method, magnetic anchor method, external forceps method, internal-traction method, double-channel-scope method, outerroute method, double-scope method, endoscopic-surgical-platform, and robot-assisted method. Each method has both advantages and disadvantages. Robotic endoscopy, enabling ESD with a traction method, will become more common due to advances in technology. In the near future, simple, noninvasive, and effective ESD using traction is expected to be developed and become established as a worldwide standard treatment for superficial gastrointestinal neoplasias.

Endoscopic Submucosal Dissection (ESD) in Colorectal Tumors

Background

Endoscopic submucosal dissection (ESD) – initially developed for the treatment of early gastric cancer in Japan – is an attractive option for en bloc resection of larger sessile or flat colorectal neoplasia.

Methods

A review of the current literature on colorectal ESD was carried out.

Results

In contrast to conventional endoscopic mucosal resection (EMR), ESD for larger colorectal neoplasia yields high en bloc resection rates and very low recurrence rates. The frequency of delayed bleeding is similar for EMR and ESD. Higher perforation rates during ESD are mostly due to microperforations identified and treated during the intervention, and are therefore of minor clinical relevance. A major disadvantage of ESD is the necessity for high-level endoscopic skills and long procedure times. ESD also has the potential to replace laparoscopic surgery or transanal endoscopic microsurgery mainly due to its lower complication rates.

Conclusion

ESD for the resection of larger flat or sessile colorectal lesions has potential advantages over conventional EMR or minimally invasive surgery. Due to the low incidence of early gastric cancer, experience with ESD will remain limited in Western countries. The spread of colorectal ESD will depend on adequate training opportunities and also on modifications yielding a reduction in procedure time.