Advantages of using thin endoscope-assisted endoscopic submucosal dissection technique for large colorectal tumors

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.

Effects of traction methods in inexperienced endoscopists during colorectal endoscopic submucosal dissection

BACKGROUND

colorectal endoscopic submucosal dissection (ESD) remains a technical challenge, but traction devices show promise in making this procedure easier. However, the efficacy of traction techniques for colorectal ESD is still unknown for inexperienced endoscopists.

METHODS

We selected 400 patients who underwent colorectal ESD performed by four inexperienced endoscopists. Each patient in the traction-assisted ESD (TA-ESD) group was matched to a patient in the conventional ESD (C-ESD) group according to propensity scores.

RESULTS

One-to-one propensity score-matching analysis created 87 matched pairs. The self-completion rate in the TA-ESD group is significantly higher than that in the C-ESD group (100% [87/87] vs. 92% [80/87], p < 0.001). The median resection speed was significantly faster in the TA-ESD group than that in the C-ESD group (27 mm2/min [IQR, 19.5-47.3] vs.18 mm2/min [IQR, 13.5-33.8], p < 0.001) and the procedure time in the TA-ESD group was significantly shorter than that in the C-ESD group (33 min [IQR, 27-47] vs.53 min [IQR, 38-73], p < 0.001). However, the histologic complete resection rate was not significantly different between the TA-ESD and C-ESD groups (93.1% [6/87]) vs. 96.6% [3/87], p < 0.1888, respectively). The en bloc resection rate (96.6%) and perforation rate (4.6%) were equivalent between the TA-ESD group and the C-ESD group.

CONCLUSION

Traction techniques seem to improve resection speed and self-completion rate of colorectal ESD for inexperienced endoscopists.

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.

The efficient of application of a fine magnetic traction system simplifies colorectal endoscopic submucosal dissection: A porcine study

BACKGROUND

Sometimes it is difficult to maintain good visualization of the submucosal layer during colorectal endoscopic submucosal dissection (ESD). This study aimed to evaluate the feasibility and efficacy of a novel traction method, the fine magnetic traction system (FMTS), in colorectal ESD.

METHODS

ESD was performed 10, 15, or 30 cm from the anus in the colorectums of 10 Bama miniature pigs with or without FMTS. The circumcision and dissection per unit time (cm²/min), en bloc resection, perforation and bleeding rates, size and integrity of the specimen and submucosal injection times were analysed.

RESULTS

A total of 60 ESD procedures were performed with or without FMTS assistance. The en bloc resection rates were 100% at 10 and 15 cm from the anus in both the control group (conventional ESD) and the FMTS group. However, at 30 cm from the anus, these rates were only 10% and 70% (p = 0.006). The resection speeds (control vs. FMTS) at the 10, 15, and 30 cm points were 0.35 ± 0.07 cm²/min vs. 0.39 ± 0.19 cm²/min (p = 0.56), 0.30 ± 0.09 cm²/min vs. 0.38 ± 0.02 cm²/min (p = 0.04), and 0.11 cm²/min vs. 0.26 ± 0.10 cm²/min, respectively.

CONCLUSIONS

The FMTS provides effective counter-traction and efficiently reduces the risks and difficulties of difficult colonic ESD in the porcine model.

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).

Present status and the future of ultrathin endoscopy

Endoscopic population-based screening for gastric cancer began in April 2016, and the use of transnasal ultrathin esophagogastroduodenoscopy (UT-EGD) has rapidly become popular. With UT-EGD, discomfort associated with an examination is reduced, patient satisfaction is high, and adverse effects on cardiopulmonary function are fewer. Consequently, UT-EGD is a good option for gastric screening in an aging society. Because of the narrower diameter of the endoscope, however, image quality is inferior to that obtained using transoral conventional esophagogastroduodenoscopy (C-EGD). As a result, lesions observed by UT-EGD must be viewed at close proximity and chromoendoscopy should be used concurrently, which is burdensome for the endoscopist. Recent innovations by endoscope manufacturers have enabled dramatic improvements in transnasal UT-EGD and facilitated Hi-Vision imaging. Furthermore, image enhancement that allows for observation on a par with transoral C-EGD is now feasible. In the future, UT-EGD will be equipped with functions that permit magnified endoscopic image. It is anticipated that a multiroute transition between transnasal and transoral UT-EGD will become possible.

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.

Novel Colorectal Endoscopic Submucosal Dissection With Double-Endoscope and Snare-Based Traction

BACKGROUND

Colorectal endoscopic submucosal dissection is technically demanding, and the traction offered by gravity, cap, or clip-with-line during conventional endoscopic submucosal dissection remains unsatisfactory. Robotic systems are still under development and are expensive. We proposed double-scope endoscopic submucosal dissection with strong and adjustable traction offered by snaring the lesion with additional scope.

OBJECTIVE

This study aimed to test the novel double-scope endoscopic submucosal dissection with snare-based traction.

DESIGN

This was a retrospective study that reviewed double-scope endoscopic submucosal dissection compared with matched conventional endoscopic submucosal dissection, and size, location, morphology, and pathology between groups were compared.

SETTINGS

This study was conducted in a referral endoscopy center in a local hospital.

PATIENTS

This study included patients with colorectal lesions receiving double-scope endoscopic submucosal dissection and matched conventional endoscopic submucosal dissection.

MAIN OUTCOME MEASURES

The pathological completeness, procedure time, and complications were analyzed.

RESULTS

Fifteen double-scope endoscopic submucosal dissection procedures, with 11 lesions located in the proximal colon with a median size of 40 mm, were performed. The median procedure time of double-scope endoscopic submucosal dissection was 32.45 (interquartile range, 16.03-38.20) minutes. The time required for second scope insertion was 2.57 (interquartile range, 0.95-6.75) minutes; for snaring, 3.03 (interquartile range, 2.12-6.62) minutes; and for actual endoscopic submucosal dissection, 28.23 (interquartile range, 7.90-37.00) minutes. All lesions were resected completely. No major complication was encountered. The procedure time was significantly shorter than that of 14 matched conventional endoscopic submucosal dissections (54.61 [interquartile range, 33.11-97.25] min; p = 0.021).

LIMITATIONS

This was a single-center, single-operator, retrospective case-controlled study with limited cases.

CONCLUSIONS

This study confirmed the feasibility of double-scope endoscopic submucosal dissection with snare-based traction to shorten procedure time and to simplify endoscopic submucosal dissection. Additional trials are required.

Colon Polypectomy with Endoscopic Submucosal Dissection and Endoscopic Full-Thickness Resection

Endoscopic resection has become the gold standard for the management of most of the large colorectal polyps. Various endoscopic resection techniques include endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and endoscopic full-thickness resection (EFTR). ESD is a minimally invasive method for the resection of advanced lesions in the gastrointestinal (GI) tract to achieve en-bloc resection. While, EFTR is more commonly used in lesions with suspected deeper submucosal invasion, lesions originating from muscularis propria, or those with advanced fibrosis. This article reviews the indications, technique, and adverse events for use of ESD and EFTR in the colon.

Endoscopic Management of Complex Colorectal Polyps: Current Insights and Future Trends

Most colorectal cancers arise from adenomatous polyps and sessile serrated lesions. Screening colonoscopy and therapeutic polypectomy can potentially reduce colorectal cancer burden by early detection and removal of these polyps, thus decreasing colorectal cancer incidence and mortality. Most endoscopists are skilled in detecting and removing the vast majority of polyps endoscopically during a routine colonoscopy. Polyps can be considered “complex” based on size, location, morphology, underlying scar tissue, which are not amenable to removal by conventional endoscopic polypectomy techniques. They are technically more challenging to resect and carry an increased risk of complications. Most of these polyps were used to be managed by surgical intervention in the past. Rapid advancement in endoscopic resection techniques has led to a decreasing role of surgery in managing these complex polyps. These endoscopic resection techniques do require an expert in the field and advanced equipment to perform the procedure. In this review, we discuss various advanced endoscopic techniques for the management of complex polyps.

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.

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.

Colorectal Endoscopic Submucosal Dissection: An Update on Best Practice

Endoscopic submucosal dissection (ESD) is a method of en-bloc resection of neoplastic colorectal lesions which is less invasive compared to surgical resection. Lesion stratification, architecture recognition and estimation of depth of invasion are crucial for patient selection. Expert endoscopists have integrated a variety of classification systems including Paris, lateral spreading tumor (LST), narrow band imaging (NBI), international colorectal endoscopic (NICE) and Japanese NBI expert team (JNET) in their day-to-day practice to enhance lesion detection accuracy. Major societies recommend ESD for LST-non granular (NG), Kudo-VI type, large depressed and protruded colonic lesions with shallow submucosal invasion. Chance of submucosal invasion enhances with increased depth as well as tumor location and size. In comparison to endoscopic mucosal resection (EMR), ESD has a lowerl recurrence rate and higher curative resection rate, making it superior for larger colonic lesions management. Major complications such as bleeding and perforation could be seen in up to 11% and 16% of patients, respectively. In major Western countries, performing ESD is challenging due to limited number of expert providers, lack of insurance coverage, and unique patient characteristics such as higher BMI and higher percentage of previously manipulated lesions.

Traction-assisted endoscopic submucosal dissection reduces procedure time and risk of serious adverse events: a systematic review and meta-analysis

BACKGROUND AND AIMS

Conventional endoscopic submucosal dissection (C-ESD) is a technically demanding procedure with prolonged procedure times and higher risk of adverse events. To overcome the procedural difficulty of ESD, several traction-assisted techniques (T-ESD) have been developed to improve visualization of the submucosa in hopes to facilitate safe and effective dissection. The aim of this study was to conduct a meta-analysis that compares short-term outcomes (30-day) of T-ESD to C-ESD.

METHODS

Clinical studies published up to April 2020 comparing the efficacy and safety of T-ESD and C-ESD were identified using electronic bibliographic searches. Both randomized controlled trials and observational studies were included. Outcomes of interests were procedure time, rates of en bloc and R0 resection, and rates of adverse events. Fixed effect and random effect model were used to calculate pooled mean difference for continuous variables and risk differences (RDs) for categorical variables.

RESULTS

Twenty-three studies with 2574 patients were included in this meta-analysis, with a total of 2582 lesions (1292 T-ESD and 1290 C-ESD). Pooled estimates of T-ESD showed shorter procedure times (weighted mean difference = -20.35 min, 95% CI -27.51 to -13.19, p < 0.001), higher R0 resection rates (RD 0.04, 95% CI 0.01-0.06, p = 0.004) and lower perforation rates (RD -0.03, 95% CI -0.04 to -0.01, p =  < 0.0001). No significant differences were seen in en bloc rates and bleeding risk between the two groups.

CONCLUSIONS

Traction-assisted ESD results in shorter procedure time, improved R0 resection rates and lower risk of perforation as compared to conventional ESD.

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.

Double-endoscope assisted endoscopic submucosal dissection for treating tumors in rectum and distal colon by expert endoscopists: a feasibility study

Background

Colorectal endoscopic submucosal dissection (ESD) is an effective but challenging procedure. To facilitate ESD, several methods that apply traction are available; however, the optimal one remains to be established. The aim of this study was to evaluate the feasibility and safety of the double-endoscope assisted ESD (DEA-ESD) by improving traction to treat complex colorectal lesions.

Methods

Naïve or previously treated lesions in the rectum and sigmoid colon were included. A grasping forceps advanced through a small-caliber endoscope (GIF-XP190N, Olympus Medical Systems, Tokyo, Japan, 5.4 mm outer diameter) was used to apply traction to the mucosal flap. Lesions were deemed complex when they exceeded a total of nine points on the SMSA scoring system (size, morphology, site, and access) and recurrent when they were previously treated with endoscopic mucosal resection (EMR). Outcome measures included procedural success, total procedure time, complications, and recurrence rate at 3-month follow-up.

Results

Nine patients (mean age 62.3 ± 14.5 years) were included; five had rectal and four had tumors in the sigmoid colon. The median SMSA score was 14 (SMSA Level IV—complex polyp), while three patients were pre-treated with EMR. DEA-ESD was technically feasible in all cases. En bloc resection and R0 resection rates were 100%, respectively, with a mean procedure time of 128.4 ± 54.1 min. No immediate or delayed complications occurred.

Conclusions

DEA-ESD is a feasible and safe method for treating complex or recurrent tumors in the rectum and distal colon.

Electronic supplementary material

The online version of this article (10.1007/s10151-020-02308-4) contains supplementary material, which is available to authorized users.

Feasibility and advantages of endoscope-assisted parotidectomy: a systematic review and meta-analysis

The object of this paper was to explore the feasibility and advantages of endoscope-assisted parotid tumour resection. Three databases (PubMed, Web of Science, and Cochrane) were used to search for all related randomised controlled trials or controlled trials (up to November 2019). The key parameters for assessment included 'Endoscope', 'Endoscopes', 'Cancer of Parotid', and 'Parotid Cancer'. To evaluate the feasibility and advantages of endoscope-assisted resection of parotid tumours, the data for each parameter were pooled, based on patients who received endoscope-assisted surgery and those who received conventional surgery. This meta-analysis included seven studies, involving 170 patients in the endoscopy group and 270 patients in the control group. The analysis using the pooled data showed that there were no significant differences in the operating times between the two groups; however, the endoscopy group had significantly shorter incisions and less intraoperative bleeding. In addition, the patients who received endoscope-assisted surgery had lower incidences of temporary facial paralysis and Frey's syndrome after surgery. Patients in the endoscopy group had greater postoperative satisfaction. Endoscope-assisted parotid tumour resection results in only a small, concealed incision wound and fewer postoperative complications. Therefore, it is promising for the surgical treatment of parotid tumours.

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.

Methods that Assist Traction during Endoscopic Submucosal Dissection of Superficial Gastrointestinal Cancers: A Systematic Literature Review

Endoscopic submucosal dissection (ESD) is a well-established method for the treatment of early-stage gastrointestinal neoplasms. Adequate submucosal exposure is one of the most significant factors related to an effective and safe dissection. The aim of this systematic review was to evaluate the effcacy and safety of various methods that assist traction during ESD of precancerous and earlystage neoplastic lesions of the gastrointestinal tract. We performed an electronic search of the MEDLINE and the Cochrane Controlled Trials Register databases for relevant studies published up to May 2019. Trials exclusively recruiting patients undergoing ESD for superficial gastrointestinal cancer were considered eligible for inclusion. Thirty-three articles including 3,134 patients met the inclusion criteria. The studies evaluated different approaches for widening the endoscopic view, including magnetic anchor-guided ESD (3 studies), use of a second endoscope (5 studies), clip-involving technique (21 studies), and miscellaneous methods (4 studies). Among them, only 6 were randomized controlled trials evaluating different approaches. Overall, the implementation of methods that assist traction during ESD significantly improved the operating time and R0 resection rate and decreased the rate of complications (bleeding and perforation). Interventions that assist traction seem effcacious in improving tissue traction, thus facilitating ESD performance.

Endoscopic submucosal dissection: an update on tools and accessories

Endoscopic submucosal dissection (ESD) is a minimally invasive therapeutic procedure to remove larger polyps or early non-metastatic lesions. It has long been used in Asia, but is now fast growing in popularity in the West. There are multiple challenges faced by ESD practitioners. While the practice of ESD in gastric lesions is relatively well established, the oesophagus with its narrow lumen and challenging workspace, and the colon with its tortuous course and folds are more challenging frontiers. The nature of performing a procedure endoscopically means that conventional methods offer no mechanism for providing counter-traction while performing dissection, impeding visibility and increasing the rate of complications. There are a multitude of tools available to those performing ESD for the different stages of the procedure. This article reviews the accessories currently used in regular ESD practice including the knives used to cut and dissect lesions, the cap and hood devices used to improve visibility and safety, injection fluids to lift the submucosal plane, haemostatic devices, generators, and finally, emerging traction apparatus. There is some evidence behind the use of these tools, however, ESD remains the domain of a small number of practitioners and the practice relies heavily on expert experience. Evolution of the ESD toolbox will make the procedure more accessible to more endoscopists, which in turn will drive the development of a more substantial evidence base to evaluate efficacy and safety of the multitude of tools.

Management of colorectal laterally spreading tumors: a systematic review and meta-analysis

Objective and study aims  To evaluate the efficacy and safety of different endoscopic resection techniques for laterally spreading colorectal tumors (LST). Methods  Relevant studies were identified in three electronic databases (PubMed, ISI and Cochrane Central Register). We considered all clinical studies in which colorectal LST were treated with endoscopic resection (endoscopic mucosal resection [EMR] and/or endoscopic submucosal dissection [ESD]) and/or transanal minimally invasive surgery (TEMS). Rates of en-bloc/piecemeal resection, complete endoscopic resection, R0 resection, curative resection, adverse events (AEs) or recurrence, were extracted. Study quality was assessed with the Newcastle-Ottawa Scale and a meta-analysis was performed using a random-effects model. Results  Forty-nine studies were included. Complete resection was similar between techniques (EMR 99.5 % [95 % CI 98.6 %-100 %] vs. ESD 97.9 % [95 % CI 96.1 - 99.2 %]), being curative in 1685/1895 (13 studies, pooled curative resection 90 %, 95 % CI 86.6 - 92.9 %, I ²  = 79 %) with non-significantly higher curative resection rates with ESD (93.6 %, 95 % CI 91.3 - 95.5 %, vs. 84 % 95 % CI 78.1 - 89.3 % with EMR). ESD was also associated with a significantly higher perforation risk (pooled incidence 5.9 %, 95 % CI 4.3 - 7.9 %, vs. EMR 1.2 %, 95 % CI 0.5 - 2.3 %) while bleeding was significantly more frequent with EMR (9.6 %, 95 % CI 6.5 - 13.2 %; vs. ESD 2.8 %, 95 % CI 1.9 - 4.0 %). Procedure-related mortality was 0.1 %. Recurrence occurred in 5.5 %, more often with EMR (12.6 %, 95 % CI 9.1 - 16.6 % vs. ESD 1.1 %, 95 % CI 0.3 - 2.5 %), with most amenable to successful endoscopic treatment (87.7 %, 95 % CI 81.1 - 93.1 %). Surgery was limited to 2.7 % of the lesions, 0.5 % due to AEs. No data of TEMS were available for LST. Conclusions  EMR and ESD are both effective and safe and are associated with a very low risk of procedure related mortality.

A snare combined with endoclips to assist in endoscopic submucosal dissection for intraepithelial neoplasia in the entire colon and rectum

OBJECTIVE

The use of mucosal traction to assist in colonic and rectal endoscopic submucosal dissection (ESD), especially for deep colonic ESD, is challenging. We developed a method of inverse insertion of a snare into the endoscopic working channel to deliver it into the colon together with the endoscope. With this method, two types of mucosal traction, per-anal external traction (PET) and per-anal internal traction (PIT), could be achieved using a snare with endoclips to assist in ESD (ESD-SE). Here, we aimed to examine its safety and feasibility.

METHODS

From January 2017 to September 2018, 50 colonic and rectal intraepithelial neoplasias in 50 patients were treated with ESD-SE. Data on lesion location and size, operation time, en bloc resection and R0 resection rates, and operative complications were collected.

RESULTS

Among 50 lesions, 15 lesions were located in the deep colon/proximal colon, and 35 lesions were in the distal colon. The median (interquartile range) size of lesions, submucosal dissection time, and total operation time were 4.5 (3.0-5.0) cm, 32 (18-81) min, and 50 (33-108) min, respectively. All lesions were completely resected, with R0 resection rates of 100%. No intraoperative and postoperative complications occurred. Postoperative pathology revealed 40 and 10 cases of high-grade and low-grade intraepithelial neoplasia, respectively.

CONCLUSIONS

The approach using insertion of a selective snare into the colon together with the endoscope, especially into the deep colon, was safe and simple. Use of the snare combined with endoclips could effectively assist in total colonic ESD. Further research is warranted.

Evaluation of endoscopic mucosal resection and endoscopic submucosal dissection in submucosal lesions of the colon and rectum

Introduction

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are commonly used for the minimally invasive treatment of submucosal lesions of the gastrointestinal tract.

Aim

To evaluate the safety, efficacy, outcome and recurrence rate of EMR and ESD for mucosal and submucosal lesions in the colon and rectum.

Material and methods

Records of 26 patients who underwent ESD and EMR for mucosal and submucosal lesions in the colon and rectum between January 2013 and March 2018 in our endoscopy unit were retrospectively reviewed.

Results

A total of 26 patients (6 female and 20 male) were evaluated. The mean age of the patients was 58.03 ±15.19 (21–80). Fifteen patients underwent ESD and EMR for rectal lesions. Tubular adenomas were found in 3 of these patients, tubulo-villous adenomas in 2, inflammatory polyps in 1, neuroendocrine tumors in 2 and carcinomas in 7 (intramucosal, in-situ and invasive). Eleven patients underwent ESD and EMR for colonic lesions. Villous adenomas were found in 2 of these patients, tubular adenoma showing dysplasia in 2, tubulo-villous adenomas showing dysplasia in 1 and carcinoma (in-situ, invasive and intramucosal) in 6. Two lesions were resected with secondary transanal local excision to obtain free margins. The follow-up period was 3 to 48 months and no recurrence was observed.

Conclusions

The EMR and ESD are reliable minimally invasive techniques with a low rate of complications and short hospital stay in the treatment of colon and rectal lesions, including early stage carcinomas of different size and morphology.

Learning colorectal endoscopic submucosal dissection: a prospective learning curve study using a novel ex vivo simulator

BACKGROUND

Endoscopic submucosal dissection (ESD) is increasingly being used in Asia as a minimally invasive therapy to eradicate large laterally spreading superficial tumors in the colon. To date, the learning curve and effectiveness of ex vivo simulators in colonic ESD training remain unclear. The aim of the study is to determine the learning curve of colonic ESD in an ex vivo simulator.

METHODS

We conducted a prospective study of colon ESD in ex vivo porcine colons in a prototype simulator. Three endoscopists with prior experience in gastric ESD but with no experience in colonic ESD each performed 30 ESD resections on standardized lesions in the rectosigmoid and left colon of the porcine simulator. Procedure time, en bloc resection status, and perforation were recorded.

RESULTS

All 90 lesions were resected using the ESD technique. The mean time of procedure was 49.6 min (standard deviation 29.6 min). The aggregate rate of perforation was 14.4% and the aggregate rate of non-en bloc resection was 5.6%. Using a composite quality score integrating complications and procedural time, it was found that there was a significant difference between two local polynomial regression lines when using a cut-point at the 9th procedure (p = 0.04), reflecting the point at which most of the learning curve is traversed.

CONCLUSIONS

In this study, there were significant improvements realized in colonic ESD performance after 9 colon ESD procedures in ex vivo specimens. Although training will depend on endoscopist skill and expertise, we suggest at least 9 ex vivo procedures prior to moving to live animal or proctored training in colonic ESD.

Colorectal endoscopic submucosal dissection: patient selection and special considerations

Endoscopic submucosal dissection (ESD) enables en bloc resection of large complex colorectal superficial neoplastic lesions, resulting in very low rates of local recurrence, high-quality pathologic specimens for accurate histopathologic diagnosis and potentially curative treatment of early adenocarcinoma without resorting to major surgical resection. The safety and efficacy of the technique, which was pioneered in the upper gastrointestinal tract, has been established by the consistently impressive outcomes from expert centers in Japan and some other eastern countries. However, ESD is challenging to perform in the colorectum and there is a significant risk of complications, particularly in the early stages of the learning curve. Early studies from western centers raised concerns about the high complication rates, and the impressive results from Japanese centers were not replicated. As a result, many western endoscopists are skeptical about the role of ESD and few centers have incorporated the technique into their practice. Nevertheless, although the distribution of expertise, referral centers and modes of practice may differ in Japan and western countries, ESD has an important role and can be safely and effectively incorporated into western practice. Key to achieving this is meticulous lesion assessment and selection, appropriate referral to centers with the necessary expertise and experience and application of the appropriate technique individualized to the patient. This review discusses the advantages, risks and benefits of ESD to treat colorectal lesions and the importance of preprocedure lesion assessment and in vivo diagnosis and outlines a pragmatic rationale for appropriate lesion selection as well as the patient, technical and institutional factors that should be considered.

Clinical outcomes after endoscopic submucosal dissection for colorectal neoplasia: a systematic review and meta-analysis

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is an endoscopic resection technique for lesions suspicious of superficial malignancy. It is performed using an ESD knife on its own (standard technique) or by the sequential use of a knife and a snare (hybrid technique). The experience with these techniques is different in Asian and non-Asian countries. We performed a systematic review and meta-analysis of available evidence on colorectal ESD.

METHODS

Electronic databases were searched up to August 2016 for studies evaluating R0, en bloc resection, and adverse event rates of both techniques for the treatment of colorectal lesions. Proportions were pooled by a random effects model.

RESULTS

Ninety-seven studies (71 performed in Asia) evaluated the standard technique and 12 studies (7 in Asia) the hybrid technique. The R0 resection rate of the standard technique was 82.9%, and it was significantly lower in non-Asian versus Asian countries: 71.3% versus 85.6%. The en bloc resection rate was 91% and was significantly lower in non-Asian versus Asian countries (81.2% vs 93%, respectively). Surgery was needed in 1.1% of the ESD-related adverse events, with a significant difference between non-Asian and Asian countries (3.1% vs 0.8%). The R0 and en bloc resection rates with the hybrid technique were significantly lower than those achieved with the standard technique: 60.6% and 68.4%, respectively, with similar adverse event rates.

CONCLUSIONS

In non-Asian countries the standard ESD technique is still failing to achieve acceptable levels of performance. The hybrid technique showed low R0 resection rates and should not be considered as an adequate alternative to the standard technique.

Technological review on endoscopic submucosal dissection: available equipment, recent developments and emerging techniques

Endoscopic submucosal dissection (ESD) is widely practiced in Japan and the Eastern World and is rapidly expanding in western countries for the management of early malignancies of the upper and lower gastrointestinal tube. In addition, novel therapeutic applications deriving from ESD have emerged including the treatment of achalasia, of submucosal tumors, of diverticula, of strictures and of reflux disease. An ESD procedure necessitates not only skills and specific training, but also familiarization with a vast spectrum of devices (endoscopes, high-frequency generators and their settings, endoknives, hoods, irrigation devices) and techniques (such as countertraction, artificial ulcer closure), that render the procedure faster, more efficient and safer. This technological article gives an overview on current and novel equipment for an ESD and associated techniques.

Recent traction methods for endoscopic submucosal dissection

Endoscopic mucosal resection (EMR) is problematic with regard to en bloc and curable resection rates. Advancements in endoscopic techniques have enabled novel endoscopic approaches such as endoscopic submucosal dissection (ESD), which has overcome some EMR problems, and has become the standard treatment for gastrointestinal tumors. However, ESD is technically difficult. Procedure time is longer and complications such as intraoperative perforation and bleeding occur more frequently than in EMR. Recently various traction methods have been introduced to facilitate ESD procedures, such as clip with line, external forceps, clip and snare, internal traction, double scope, and magnetic anchor. Each method must be used appropriately according to the anatomical characteristics. In this review we discuss recently proposed traction methods for ESD based on the characteristics of various anatomical sites.

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.

Deep colonic endoscopic submucosal dissection using a modified clip and snare method incorporating a pre-looping technique

Endoscopic submucosal dissection (ESD) is more difficult to perform for colorectal cancer than for early gastric cancer. The use of traction to facilitate direct submucosal layer visualisation is promising in reducing the procedure's time and complication rate. We report a case in which deep colonic ESD was performed with a modified clip and snare method. A 57-year-old man was admitted for ESD of a laterally spreading caecal lesion 25 mm in size (classified as LST-GM) that had been found on colonoscopy. The clip and snare method was previously developed for ESD of gastric cancer; we improved on this method and applied our pre-looping technique in the deep colon. The procedure lasted 40 min and was without complications. Our pre-looping technique represents a modification of the clip and snare method, enabling its performance in the deep colon. We expect that our technique will be applicable to colorectal tumours.

Prospective clinical trial of traction device-assisted endoscopic submucosal dissection of large superficial colorectal tumors using the S-O clip

BACKGROUND

Endoscopic submucosal dissection (ESD) allows en bloc resection of superficial colorectal tumors regardless of size. However, ESD is technically difficult, hazardous, and time consuming. New devices may help overcome these drawbacks. We focused on traction methods and designed a new traction device, the "S-O clip." Its main advantage is that it allows direct visualization of the cutting line during submucosal dissection. Moreover, it can be used at any location without withdrawing the endoscope. The purpose of this study was to evaluate the efficacy and safety of traction device-assisted ESD for large colorectal tumors using the S-O clip.

METHODS

Between August 2010 and December 2011, ESD was performed in 70 patients with a superficial colorectal tumor ≥20 mm in diameter in our department. Patients were randomized into two groups: 27 cases in the S-O clip-assisted ESD group and 23 cases in the conventional ESD group. Included in the analysis were patient's gender and age, tumor form, size, and location, rate of en bloc resection, procedure time, presence or absence of intraoperative perforation or delayed bleeding, and pathological findings. Subgroup analysis stratified by these factors and multivariate analyses were conducted.

RESULTS

In the S-O clip-assisted ESD group, all 27 tumors were resected en bloc without any complications. Although a micro perforation occurred in one patient in the conventional ESD group, further surgical treatment was not required. None of the other 22 cases in the conventional ESD group experienced complications. The mean procedure time for the S-O clip-assisted ESD group was significantly shorter than for the conventional ESD group (37.4 ± 32.6 vs. 67.1 ± 44.1 min, p = 0.03). No significant between-group differences were found for the other factors.

CONCLUSION

Our results demonstrated that S-O clip-assisted ESD is safe and fast for en bloc resection of large superficial colorectal tumors.

Prospective, randomized comparison of a prototype endoscope with deflecting working channels versus a conventional double-channel endoscope for rectal endoscopic submucosal dissection in an established experimental simulation model (with video)

BACKGROUND

A prototype endoscope was designed to improve visualization and dissection of tissue with the use of 2 working channels with different deflections.

OBJECTIVE

To evaluate the efficacy and operability of a prototype endoscope in comparison with a conventional double-channel endoscope for rectal endoscopic submucosal dissection (ESD).

DESIGN

Randomized, prospective, controlled, ex vivo study.

SETTING

Academic medical center.

METHODS

A total of 80 standardized artificial lesions measuring 3 × 3 cm were created approximately 5 cm from the anal verge in fresh ex vivo porcine colorectal specimens. Two endoscopists each completed 20 cases with the prototype endoscope and 20 cases with the conventional endoscope.

MAIN OUTCOME MEASUREMENTS

An independent observer recorded procedure time, specimen size, en bloc resection, and perforation rate.

RESULTS

For the ESD novice, the mean submucosal dissection time (10.5 ± 3.8 vs 14.9 ± 7.3 minutes; P = .024) and total procedure time (18.1 ± 5.2 vs 23.6 ± 8.2 minutes; P = .015) were significantly shorter in the prototype group in comparison with the conventional group. For the ESD expert, there was no significant difference between the mean circumferential resection, submucosal dissection, and total procedure time (prototype group 14.2 ± 6.0 minutes, conventional group 14.2 ± 8.8 minutes; P = .992). The overall perforation and en bloc resection rates were not significantly different between groups.

LIMITATIONS

Ex vivo study.

CONCLUSION

In this ex vivo prospective comparison study, there was a technical advantage for the ESD novice with the prototype endoscope that resulted in a shorter procedure time, which was not observed for cases performed by the ESD expert.

Systematic review and meta-analysis of endoscopic submucosal dissection versus transanal endoscopic microsurgery for large noninvasive rectal lesions

BACKGROUND

For almost 30 years, transanal endoscopic microsurgery (TEM) has been the mainstay treatment for large rectal lesions. With the advent of endoscopic submucosal dissection (ESD), flexible endoscopy has aimed at en bloc R0 resection of superficial lesions of the digestive tract. This systematic review and meta-analysis compared the safety and effectiveness of ESD and full-thickness rectal wall excision by TEM in the treatment of large nonpedunculated rectal lesions preoperatively assessed as noninvasive.

METHODS

A systematic review of the literature published between 1984 and 2010 was conducted (Registration no. CRD42012001882). Data were integrated with those from the original databases requested from the study authors when needed. Pooled estimates of the proportions of patients with en bloc R0 resection, complications, recurrence, and need for further treatment in the ESD and TEM series were compared using random-effects single-arm meta-analysis.

RESULTS

This review included 11 ESD and 10 TEM series (2,077 patients). The en bloc resection rate was 87.8 % (95 % confidence interval [CI] 84.3-90.6) for the ESD patients versus 98.7 % (95 % CI 97.4-99.3 %) for the TEM patients (P < 0.001). The R0 resection rate was 74.6 % (95 % CI 70.4-78.4 %) for the ESD patients versus 88.5 % (95 % CI 85.9-90.6 %) for the TEM patients (P < 0.001). The postoperative complications rate was 8.0 % (95 %, CI 5.4-11.8 %) for the ESD patients versus 8.4 % (95 % CI 5.2-13.4 %) for the TEM patients (P = 0.874). The recurrence rate was 2.6 % (95 % CI 1.3-5.2 %) for the ESD patients versus 5.2 % (95 % CI 4.0-6.9 %) for the TEM patients (P < 0.001). Nevertheless, the rate for the overall need of further abdominal treatment, defined as any type of surgery performed through an abdominal access, including both complications and pathology indications, was 8.4 % (95 % CI 4.9-13.9 %) for the ESD patients versus 1.8 % (95 % CI 0.8-3.7 %) for the TEM patients (P < 0.001).

CONCLUSIONS

The ESD procedure appears to be a safe technique, but TEM achieves a higher R0 resection rate when performed in full-thickness fashion, significantly reducing the need for further abdominal treatment.

Systematic review and meta-analysis of endoscopic submucosal dissection versus transanal endoscopic microsurgery for large noninvasive rectal lesions

BACKGROUND

For almost 30 years, transanal endoscopic microsurgery (TEM) has been the mainstay treatment for large rectal lesions. With the advent of endoscopic submucosal dissection (ESD), flexible endoscopy has aimed at en bloc R0 resection of superficial lesions of the digestive tract. This systematic review and meta-analysis compared the safety and effectiveness of ESD and full-thickness rectal wall excision by TEM in the treatment of large nonpedunculated rectal lesions preoperatively assessed as noninvasive.

METHODS

A systematic review of the literature published between 1984 and 2010 was conducted (Registration no. CRD42012001882). Data were integrated with those from the original databases requested from the study authors when needed. Pooled estimates of the proportions of patients with en bloc R0 resection, complications, recurrence, and need for further treatment in the ESD and TEM series were compared using random-effects single-arm meta-analysis.

RESULTS

This review included 11 ESD and 10 TEM series (2,077 patients). The en bloc resection rate was 87.8 % (95 % confidence interval [CI] 84.3-90.6) for the ESD patients versus 98.7 % (95 % CI 97.4-99.3 %) for the TEM patients (P < 0.001). The R0 resection rate was 74.6 % (95 % CI 70.4-78.4 %) for the ESD patients versus 88.5 % (95 % CI 85.9-90.6 %) for the TEM patients (P < 0.001). The postoperative complications rate was 8.0 % (95 %, CI 5.4-11.8 %) for the ESD patients versus 8.4 % (95 % CI 5.2-13.4 %) for the TEM patients (P = 0.874). The recurrence rate was 2.6 % (95 % CI 1.3-5.2 %) for the ESD patients versus 5.2 % (95 % CI 4.0-6.9 %) for the TEM patients (P < 0.001). Nevertheless, the rate for the overall need of further abdominal treatment, defined as any type of surgery performed through an abdominal access, including both complications and pathology indications, was 8.4 % (95 % CI 4.9-13.9 %) for the ESD patients versus 1.8 % (95 % CI 0.8-3.7 %) for the TEM patients (P < 0.001).

CONCLUSIONS

The ESD procedure appears to be a safe technique, but TEM achieves a higher R0 resection rate when performed in full-thickness fashion, significantly reducing the need for further abdominal treatment.

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

Colorectal endoscopic submucosal dissection (ESD) still remains a technically difficult procedure. The maintenance of tissue tension and good submucosal exposure during dissection is one of the most important factors for an effective and safe dissection. Although various traction methods have been developed, traction by gravity is one of the most useful method for colorectal ESD. Traction using adjunctive devices can thus be reserved for extremely difficult cases or for endoscopists in their learning periods for colorectal ESD.

Recurrence after curative surgical resection of T1 rectal cancer: a report of two cases

Recent advances in endoscopic diagnosis and treatment techniques have led to a marked increase in the detection and endoscopic treatment of early colorectal cancers (CRC). According to the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines, T1-CRC with a negative vertical margin, well- or moderately differentiated adenocarcinoma, no evidence of vascular or lymphatic invasion, and depth of invasion <1000 μm are considered to have a low risk of lymph node metastasis. However, T1-CRC with any of these risk factors are considered to have a high risk of lymph node metastasis. T1-CRC is considered to have a good prognosis if additional surgery is carried out. We experienced two cases of recurrence despite curative surgical resection of T1 rectal cancer.

Metachronous adenoma on ileorectal anastomosis suture line and submucosal deep invasive cancer suspected of rapid growth in rectal remnant following long-term interval after curative surgery for advanced colon cancer

There is general agreement as to the value of postoperative surveillance and the effectiveness of colonoscopy in the early detection of metachronous colorectal lesions. In the present case, a 56-year-old woman with no family history of colon cancer underwent surveillance colonoscopy in which a metachronous flat adenoma was detected following an interval of 23 years after a colectomy and 20 years subsequent to treatment for uterine cancer. A second metachronous flat lesion histopathologically determined to be a submucosal (sm) deep invasive cancer with lymphovascular involvement was detected 12 months later. This second metachronous lesion was suspected of having developed rapidly in the rectal remnant accounting for its sm deep invasion. The findings of this case suggest colonoscopy surveillance guidelines proposed for individuals at high risk should be evaluated based on cancer history and an analysis of possible mismatch repair gene mutations. In addition, the first metachronous lesion was located directly on the suture line of the anastomosis. Endoscopic submucosal dissection (ESD) was indicated despite severe fibrosis into the sm layer. This case also demonstrates the successful use of improved ESD instruments, sm injection agents and technique refinements in the treatment of a technically difficult lesion with a high risk of complications.

Colorectal endoscopic submucosal dissection: is it suitable in western countries?

Endoscopic submucosal dissection (ESD) represents a significant advance in therapeutic endoscopy with the major advantage being the ability to achieve a higher en bloc resection rate for early stage lesions. Western endoscopists infrequently perform colorectal ESD (CR-ESD) because of the greater technical difficulty involved, longer procedure times, and increased risk of perforation. Specialized training and sufficient clinical experience are necessary to successfully perform ESDs, but a systematic education and training program has still not been established in Japan or elsewhere in the world. Experts generally acknowledge that the stomach is the first organ in which endoscopists should begin performing ESDs. The incidence and detection rates for early stage gastric cancer are significantly higher in Japan than in western countries, so Japanese endoscopists have a greater opportunity to perform gastric ESDs than their western counterparts. It is logical to ask, therefore, whether CR-ESD can be effectively applied in western countries. Based on a review of the relevant literature and our practical perspective, we have focused on the progress made in performing CR-ESD, its indications, training methods, and learning curve. Use of animal gastric and colon models is strongly recommended along with accumulating the necessary experience from the rectum to the colon on a step-by-step basis. It is reasonable to assume that an increasing number of CR-ESDs will be performed by western endoscopists in the foreseeable future given the continuing development of new techniques, and the refinement of instruments and other technologically advanced devices together with the creation of even more effective submucosal injection agents.

High efficacy of endoscopic submucosal dissection for rectal laterally spreading tumors larger than 3 cm

BACKGROUND

Endoscopic submucosal dissection (ESD) was recently developed to allow en bloc resection of early neoplasia of the GI tract, including colorectal neoplasia. The endoscopic technique is technically demanding and not yet standardized, and new devices are needed.

OBJECTIVE

This study aimed to evaluate the efficacy and safety of a new device that combines the functions of injection and cutting.

DESIGN

Prospective, pilot, single-arm study.

METHODS

Consecutive patients with rectal laterally spreading tumors (LSTs) 3 cm or larger unsuitable for en bloc resection were enrolled. ESD was performed with a new device that allows cutting and coagulation as well as a needleless, tissue-selective mucosal and submucosal elevation through an axial water-jet channel.

MAIN OUTCOME MEASUREMENT

The primary endpoint of the study was the en bloc resection rate achieved with ESD in a Western hospital setting.

RESULTS

Overall, ESD was attempted in 40 consecutive patients (27 male, mean age 65.3 years) with rectal LSTs larger than 3 cm (72.5% LSTs, nongranular type, 5% depressed type, 22.5% protruding type). The mean lesion size was 46.8 ± 10.9 mm (range 33-80 mm). The mean procedure time was 86.1 ± 35.5 minutes (range 40-190 minutes). The en bloc resection rate was 90% (36/40). In the remaining patients, resection was completed with a piecemeal approach. The rate of curative resection (R0) was 32 of 40 LSTs (80%). Two patients with submucosal invasion were referred for surgery. Perforation occurred in 1 patient (2.5%), which was managed conservatively. Postoperative bleeding occurred in 2 patients (5%) and was treated by endoscopic hemostasis.

LIMITATIONS

Single-center study with a relatively small number of patients.

CONCLUSIONS

ESD is a safe and effective method to provide en bloc and curative resection of large rectal LSTs. The operating time and adverse event rate were comparable to those of previously published data from Japanese experts.

Counter traction makes endoscopic submucosal dissection easier

Poor counter traction and poor field of vision make endoscopic submucosal dissection (ESD) difficult. Good counter traction allows dissections to be performed more quickly and safely. Position change, which utilizes gravity, is the simplest method to create a clear field of vision. It is useful especially for esophageal and colon ESD. The second easiest method is clip with line method. Counter traction made by clip with line accomplishes the creation of a clear field of vision and suitable counter traction thereby making ESD more efficient and safe. The author published this method in 2002. The name ESD was not established in those days; the name cutting endoscopic mucosal resection (EMR) or EMR with hook knife was used. The other traction methods such as external grasping forceps, internal traction, double channel scope, and double scopes method are introduced in this paper. A good strategy for creating counter traction makes ESD easier.

Ex vivo comparative study using the Endolifter® as a traction device for enhancing submucosal visualization during endoscopic submucosal dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) is a technically demanding procedure, and exposure of the submucosa depends on the action of gravity and submucosal injection. The aim of the study was to investigate the effectiveness of the Endolifter(®) as a traction device for enhancing submucosal visualization during ESD.

METHODS

This was a prospective ex vivo comparative study conducted between September 2010 and March 2011 in the Prince of Wales Hospital. Consecutive ESDs were performed by four experienced endoscopists in an ex vivo ESD model with or without the Endolifter(®). The Endolifter(®) allows simultaneous grasping, retracting and lifting of the mucosa during ESD, resulting in exposure of the submucosa. Each of the procedures were recorded and reviewed later by two independent assessors. The outcome measures included the proportion of time that the submucosa was visualized during the procedures (SM ratio), procedural times, perforation rates, amount of submucosal injections, and the difficulty of the procedure.

RESULTS

Forty-eight gastric ESD procedures were performed on the model. The SM ratio was higher in the Endolifter(®) group (P = 0.007), particularly for lesions located at the antrum (P < 0.001). The time required for submucosal dissection and the total procedural time were also less in the Endolifter(®) group. The endoscopists rated the ESD procedures in the Endolifter(®) group as less difficult (P = 0.033).

CONCLUSIONS

The Endolifter(®) improved submucosal visualization during gastric ESD and reduces the difficulty of performing the procedures. The device may improve the ease of performing ESD in low-volume centers or large mucosal lesions.

Supportive techniques and devices for endoscopic submucosal dissection of gastric cancer

The indications for endoscopic treatment have expanded in recent years, and relatively intestinal-type mucosal stomach carcinomas with a low potential for metastasis are now often resected en bloc by endoscopic submucosal dissection (ESD), even if they measure over 20 mm in size. However, ESD requires complex maneuvers, which entails a long operation time, and is often accompanied by complications such as bleeding and perforation. Many technical developments have been implemented to overcome these complications. The scope, cutting device, hemostasis device, and other supportive devices have been improved. However, even with these innovations, ESD remains a potentially complex procedure. One of the major difficulties is poor visualization of the submucosal layer resulting from the poor countertraction afforded during submucosal dissection. Recently, countertraction devices have been developed. In this paper, we introduce countertraction techniques and devices mainly for gastric cancer.

Endoscopic submucosal dissection for large colorectal tumors using a cross-counter technique and a novel large-diameter balloon overtube

BACKGROUND AND AIM

Endoscopic submucosal dissection (ESD) in early gastric cancer (EGC), which provides a higher complete resection rate than conventional endoscopic mucosal resection (EMR), has rapidly come into widespread use. However, colorectal ESD is not widely used because of its technical difficulty and complications such as perforation, and the procedure time is longer than that of conventional EMR. Development of safer and more reliable devices as well as technique modifications are therefore required. The aim of our study is to compare safety and efficacy of a new traction method, the cross-counter technique, for large colorectal tumors combined with a balloon overtube.

METHODS

A total of 30 patients with large colorectal tumors were analyzed retrospectively; 15 patients for the cross-counter technique group (CC group) and 15 patients for the no-traction group (NT group). Procedure time, complete resection rate, perforation rate and bleeding rate were assessed.

RESULTS

The procedure time was 126 ± 42.2 min and 165 ± 61.3 min in the CC and NT groups, respectively, and there was a significant difference between the two groups (P < 0.05). There were no significant differences in complete resection rate, perforation rate and bleeding rate between the two groups.

CONCLUSION

The cross-counter technique shortened the treatment time in colorectal ESD without any complication.

[Endoscopic submucosal dissection: only for expert endoscopists?]

Endoscopic submucosal dissection (ESD) can be applied to early gastrointestinal cancers. This technique was developed to achieve radical curative resection and to reduce unnecessary surgical interventions. ESD was designed in eastern countries and is not widely used in the West. Although ESD represents a major therapeutic advance in endoscopy and is performed with curative intent, the complication rate (hemorrhage, perforation) is higher than reported in other techniques, requiring from endoscopists the acquirement of technical skill and experience through a structured and progressive training program to reduce the morbidity associated with this technique and increase its potential benefits. Although there is substantial published evidence on the applications and results of ESD, there are few publications on training in this technique and a standardized training program is lacking. The current article aims to describe the various proposals for training, as well as the basic principles of the technique, its indications, and the results obtained, since theoretical knowledge that would guide endoscopists during the clinical application of ESD is advisable before training begins. Training in an endoscopic technique has a little value without knowledge of the technique's aims, the situations in which it should be applied, and the results that can be expected.