Efficacy of novel SB knife Jr examined in a multicenter study on colorectal endoscopic submucosal dissection

Efficacy of Two Kinds of Scissor-Type Knives for Colorectal Endoscopic Submucosal Dissection: A Retrospective Comparative Study

INTRODUCTION

Scissor-type knives are spreading as safe devises in endoscopic submucosal dissection (ESD). We evaluated the efficacy of two kinds of scissor-type knives (Clutch Cutter: CC, Fujifilm Co. and SB Knife Jr2: SB, SB-KAWASUMI Laboratories. Inc.) in colorectal ESD.

METHODS

This single-center retrospective study analyzed 178 ESD cases treated with CC from January 2020 to August 2021 and 91 cases with SB from September 2021 to December 2023. The two groups were compared through propensity score matching. Therapeutic results, such as ESD procedure time, en bloc resection rate, perioperative bleeding frequency, and complications, were analyzed in each group. Risk factors for long ESD procedure time (≥ 90 min) were also examined.

RESULTS

After matching, 87 cases in each group were analyzed. There was no significant difference in the ESD procedure time (min, median [interquartile range]) between the CC and SB groups (54.0 [36.0-72.0] vs. 53.0 [39.0-72.0], p = 0.99). Additionally, there were no differences in the en bloc resection (100% vs. 100%, p = 1.00), perioperative perforation (1.1% vs. 1.1%, p = 1.00), or delayed bleeding (1.1% vs. 0.0%, p = 1.00). There was a significant difference in perioperative bleeding frequency (mean ± standard deviation: 1.8 ± 2.6 vs. 3.0 ± 3.5, p < 0.01). The significant risk factors (odds ratio [95% confidence interval]) for long ESD procedure time in patients treated with CC or SB were antiplatelet (7.51 [1.82-31.00]), large lesion size (1.08 [1.05-1.12]), severe fibrosis (24.30 [7.60-77.90]), and perioperative bleeding frequency (1.34 [1.14-1.56]).

CONCLUSIONS

CC and SB in colorectal ESD enabled high en bloc resection and low complication rates. CC showed significantly less perioperative bleeding than SB.

Is there a best choice of equipment for colorectal endoscopic submucosal dissection?

INTRODUCTION

Endoscopic submucosal dissection (ESD) is a widely used technique to remove early neoplastic lesions. It was primarily used in the initial days to treat gastric lesions, but recently, the horizon of this endoscopic procedure has expanded, which has allowed us to manage other technically more complex locations, such as the colorectum.

AREAS COVERED

There has been an exponential growth regarding the wide range of devices available in the market for performing colorectal ESD. As a result, the aim of this review is to highlight the indication of this endoscopic technique, which device is best suited for which indication, as well as future trajectories in this field.

EXPERT OPINION

Although some devices have proven to be more advantageous than others in this area, very often the choice is still subjective, which is commonly attributed to individual preferences and experience. However, an accurate knowledge of the available tools and their functioning, with their pros and cons, is fundamental for any endoscopist venturing into the field of third space endoscopy. In this way, one can choose which device best suits a particular situation, along with simultaneously having the wealth of knowledge related to therapeutic armamentarium at our disposal in the endoscopy suite.

Efficacy of a Traction Device for Endoscopic Submucosal Dissection Using a Scissor-Type Knife: A Randomized Controlled Trial

INTRODUCTION

Although safe, colorectal endoscopic submucosal dissection (ESD) using a scissor-type knife has a slow resection speed. We aimed to evaluate the efficacy of a traction device to hasten the resection speed.

METHODS

This multicenter randomized controlled trial was conducted at 3 Japanese institutions. Patients with a 20-50-mm superficial colorectal tumor were enrolled and randomly assigned to a conventional-ESD (C-ESD) group or a traction-assisted ESD (T-ESD) group. The primary outcome was the resection speed.

RESULTS

The C-ESD and T-ESD groups comprised 49 and 48 patients, respectively. Although the mean resection speed was not significantly different in the entire cohort between the groups (23.7 vs 25.6 mm 2 /min, respectively; P = 0.43), it was significantly faster with T-ESD than with C-ESD at the cecum (32.4 vs 16.7 mm 2 /min, respectively; P = 0.02). The mean resection speed of tumors ≥30 mm tended to be faster by T-ESD than by C-ESD (34.6 vs 27.8 mm 2 /min, respectively; P = 0.054). The mean procedure time of T-ESD was significantly shorter than that of C-ESD (47.3 vs 62.3 minutes, respectively; P = 0.03). The en bloc (100% vs 100%), complete (98.0% vs 97.9%), and curative resection (93.9% vs 91.7%) rates were similar between the 2 groups. Perforation and delayed hemorrhage occurred in only 1 patient each in the T-ESD group.

DISCUSSION

Although the resection rates were sufficiently high and adverse event rates were extremely low in both the groups, the use of a traction device for ESD in the proximal colon and for large lesions may increase the resection speed.

Efficacy and safety comparison of scissor-type knives with needle-type knives for colorectal endoscopic submucosal dissection: a post-hoc propensity score-matched analysis (with videos)

BACKGROUND AND AIMS

Many knives have been developed to improve the efficacy and safety of endoscopic submucosal dissection (ESD). We aimed to evaluate the efficacy and safety of scissor-type knives for colorectal ESD compared with needle-type knives.

METHODS

We performed a post-hoc propensity score-matched analysis in an 11-facility study between August 2013 and December 2018. A total of 2330 patients (2498 lesions) who underwent colorectal ESD were divided into needle-type (1923 patients, 2067 lesions) and scissor-type (407 patients, 431 lesions) knife groups. Short-term outcomes were compared between the 2 groups.

RESULTS

Two-to-one propensity score-matched analysis identified 814 (709 patients) and 407 (386 patients) lesions in the needle- and scissor-type knife groups, respectively. The median resection speed was significantly faster in the needle-type group (18.3 mm²/min) than in the scissor-type group (13.2 mm²/min, P < .0001), whereas en-bloc and histologic complete resection rates were not significantly different between the needle- and scissor-type groups (96.8% [788/814] vs 98.3% [400/407], P = .1888 and 95.1% [774/814] vs 95.6% [389/407], P = .7763, respectively). The rate of lesions resected using a single knife was significantly higher in the scissor-type group (98.5% [401/407]) than in the needle-type group (43.9% [357/814], P < .0001). Rates of intraoperative perforation and delayed bleeding were significantly lower in the scissor-type group than in the needle-type group (.7% [3/407] vs 2.5% [20/814], P = .0431 for each).

CONCLUSIONS

Scissor-type knives are safer for colorectal ESD. However, they are associated with slower resection speeds compared with needle-type knives. (Clinical trial registration number: UMIN000016197.).

Expert consensus on the clinical application of high-frequency electrosurgery in digestive endoscopy (2020, Shanghai)

High-frequency electrosurgery has been widely applied in digestive endoscopy with constantly expanding indications. However, high-frequency electrosurgery may cause possible complications such as hemorrhage or perforation during or after the procedure, of which endoscopists must be cautious. Digestive endoscopists must have a firm grasp of the principles of high-frequency electrosurgery as well as its safety issues so as to improve the safety of its clinical application. To this end, experts in gastroenterology and hepatology, digestive endoscopy, surgery, nursing and other related fields were invited to draft a consensus on the clinical application of high-frequency electrosurgery in digestive endoscopy based on relevant domestic and international literatures and their experiences.

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

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

Learning curve for endoscopic submucosal dissection of early colorectal neoplasms with a monopolar scissor-type knife: use of the cumulative sum method

OBJECTIVE

Although scissor-type knives such as the Stag-Beetle (SB) Knife Jr are expected to result in a safe and easy colorectal endoscopic submucosal dissection (CR-ESD), information regarding the learning curve is lacking. Therefore, this study evaluated the learning curve with using SB Knife Jr.

MATERIALS AND METHODS

We retrospectively reviewed 507 CR-ESD procedures performed in 464 patients using SB Knife Jr. The primary endpoint was a learning curve to achieve a satisfactory complete resection rate. The secondary endpoints were learning curves to achieve a satisfactory en bloc resection rate, curative resection rate, and resection speed.

RESULTS

The complete, en bloc, and curative resection rates were 91.9%, 95.9%, and 84.0%, respectively. Moving average analysis showed that 39 cases were required for a complete resection rate of >80%, 41 for an en bloc resection rate of >90%, and 50 for a curative resection rate of >75%. We divided the procedure into three phases using the cumulative sum method: I, II, and III (cases 1-36, 37-119, and 120-507, respectively). Although we found no significant between-phase differences, the complete resection rate showed an increasing trend in Phase III (83.3 vs. 89.2 vs. 93.3%; p = .099). The en bloc resection rate (91.7 vs. 91.6 vs. 97.2%; p = .047) and resection speed (20.5 vs. 7.2 vs. 6.8 min/cm²; p < .001) were greater in Phase III. Despite the larger specimen size (27.3 vs. 38.2 vs. 40.4 mm; p < .001) and more severe fibrosis (p < .001) in Phase III, the procedure time was shorter (73.8 vs. 57.8 vs. 54.2 min; p = .041). The curative resection rate was not significantly different between phases.

CONCLUSIONS

SB Knife Jr enables safe and easy CR-ESD during the introductory period compared to the conventional tip-type knife and has an acceptable learning curve. Therefore, using this knife will encourage the widespread adoption of CR-ESD in Asian general hospitals and non-Asian countries.

Prospective randomized trial comparing the pocket-creation method and conventional method of colorectal endoscopic submucosal dissection

BACKGROUND AND AIMS

Colorectal endoscopic submucosal dissection (ESD) is recognized as a challenging procedure. Previously, we reported that a new ESD strategy using the pocket-creation method (PCM) is useful for colorectal ESD, but no prospective randomized study has evaluated the efficacy of the PCM. The aim of this study was to evaluate the efficacy and safety of PCM for colorectal ESD compared with the conventional method (CM).

METHODS

This was a prospective randomized controlled trial at 3 institutions in Japan. Patients with superficial colorectal neoplastic lesions >20 mm predicted to be intramucosal were randomly assigned to undergo ESD using the PCM or CM. Primary outcome was the ESD completion rate defined as completion of colorectal ESD with an en bloc resection using the assigned ESD method without changing to other methods or assisted by other devices.

RESULTS

We analyzed 59 patients with 59 colorectal tumors in the PCM group and 55 in the CM group. The ESD completion rate was significantly higher in the PCM group compared with the CM group (93% [55/59] vs 73% [40/55]; P  = .01). En bloc resection rates, R0 resection rates, procedure time, and dissection speed were not significantly different between the 2 groups. The incidence of adverse events was similar in the 2 groups.

CONCLUSIONS

Use of the PCM allows the endoscopist to complete the procedure with the intended method more often than the CM with similar clinical outcomes. (Clinical trial registration number: UMIN 000024394.).

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.

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.

Efficacy of scissor-type knives for endoscopic mucosal dissection of superficial gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) for superficial gastrointestinal neoplasms has become widespread. However, certain aspects of the procedure remain difficult to manage, such as intraoperative bleeding and perforation. There are two kinds of scissor-type knife: the Clutch Cutter (Fujifilm Co., Tokyo, Japan) and the SB knife (Sumitomo Bakelite Co., Tokyo, Japan). These knives have different features from other types of ESD knives and enable the performance of all ESD procedures, including mucosal incision, submucosal dissection, and hemostasis. The standard approach with scissor-type knives involves first grabbing the tissue and then incising or dissecting it. Theoretically, perforation as a result of unintentional movement should never happen with scissor-type knives compared to needle- or blade-type knives, which may induce perforation through unintentional movement. Moreover, the rates of severe bleeding and self-completion of ESD with scissor-type knives by non-experts were reported to be significantly better than for other knives. Thus, scissor-type knives can resolve these problems and help to further standardize ESD globally. In this review, we summarize reports on the efficacy of such scissor-type knives for ESD of gastrointestinal tumors. We also present the pocket-creation method and the application of traction devices, such as dental floss and S-O clips (Zeon Medical Co., Tokyo, Japan) for improving the performance of ESD with a Clutch Cutter.

Endoscopic submucosal dissection of colorectal neoplasms: an audit of its safety and efficacy in a single tertiary centre in Singapore

INTRODUCTION

Endoscopic submucosal dissection (ESD) provides a higher en bloc and R0 resection rate than endoscopic mucosal resection. Colorectal ESD is not widely used because of its technical difficulty and risk of complications, especially for right-sided colonic lesions. We audited the clinical outcomes of our initial experience with colorectal ESD.

METHODS

We reviewed data collected from a prospective registry of patients who underwent colorectal ESD from December 2014 to March 2018. Therapeutic outcomes and procedure-related complications were analysed.

RESULTS

A total of 41 patients (mean age 67.4 years, 21 male) underwent colorectal ESD. The distribution of the lesions was as follows: rectum (n = 9), sigmoid colon (n = 8), descending colon (n = 6), splenic flexure (n = 1), transverse colon (n = 5), ascending colon (n = 8) and caecum (n = 4). The mean size was 23 (range 12-50) mm. En bloc resection was achieved in 35 (85.4%) out of 41 patients, and R0 resection or clear resection margins was achieved in 33 (94.3%) of the en bloc resection patients. The lesion was upstaged in 14 (34.1%) patients after ESD. Colonic perforation occurred in 3 (7.3%) patients during ESD and was successfully treated with endoscopic clips. There was no procedure-related bleeding. No patient required surgery for management of complications. The median duration of hospitalisation was 1 (range 0-7) day. Four patients with lesions that were upstaged after ESD, from high-grade dysplasia to intramucosal carcinoma with deep submucosal invasion, were referred for colectomy.

CONCLUSION

Our early outcome data was comparable to that from large published series. ESD is an effective and feasible treatment for colorectal lesions.

Comparing outcomes for endoscopic submucosal dissection between Eastern and Western countries: A systematic review and meta-analysis

AIM

To compare endoscopic submucosal dissection (ESD) outcomes between Eastern and Western countries.

METHODS

A systematic review and meta-analysis was performed using PubMed, MEDLINE, Web of Science, CINAHL and EBM reviews to identify studies published between 1990 and February 2016. The primary outcome was the efficacy of ESD based on information about either curative resection, en bloc or R0 resection rates. Secondary outcomes were complication rates, local recurrence rates and procedure times.

RESULTS

Overall, 238 publications including 84318 patients and 89512 gastrointestinal lesions resected using ESD were identified. 90% of the identified studies reporting ESD on 87296 lesions were conducted in Eastern countries and 10% of the identified studies reporting ESD outcomes in 2216 lesions were from Western countries. Meta-analyses showed higher pooled percentage of curative, en bloc, and R0 resection in the Eastern studies; 82% (CI: 81%-84%), 95% (CI: 94%-96%) and 89% (CI: 88%-91%) compared to Western studies; 71% (CI: 61%-81%), 85% (CI: 81%-89%) and 74% (CI: 67%-81%) respectively. The percentage of perforation requiring surgery was significantly greater in the Western countries (0.53%; CI: 0.10-1.16) compared to Eastern countries (0.01%; CI: 0%-0.05%). ESD procedure times were longer in Western countries (110 min vs 77 min).

CONCLUSION

Eastern countries show better ESD outcomes compared to Western countries. Availability of local ESD expertise and regional outcomes should be considered for decision making to treat gastrointestinal lesions with ESD.

Efficacy and Safety of Flexible Endoscopic Management of Zenker's Diverticulum

Zenker's diverticulum (ZD), a pulsion diverticulum of hypopharynx is a rare but treatable cause of morbidity in geriatric population. Traditionally a surgical disease but due to its associated high morbidity, flexible endoscopy has become a lucrative option. We reviewed 997 patients from 23 original studies who underwent flexible endoscopic diverticulotomy (FED) of ZD. Composite technical and clinical success rate for the study cohort was 99.4% and 87.9%, respectively. Composite failure rate was 10.0% but close to half of them (45.3%) had success with repeat endoscopic intervention. Composite rate for symptom recurrence after long-term follow-up was 13.6% but more than half (61.8%) had success with repeat endoscopic intervention. Bleeding (6.6%) and perforation (5.3%) were 2 most common complications of FED. All bleeding events were successfully managed with observation or endoscopic therapy. Majority of perforation events (4.4%) were successfully managed with conservative care and only 0.9% required invasive management. No mortality was reported. Efficacy and safety of FED of ZD remained same irrespective of diverticulum size or prior surgical/endoscopic treatment. FED with diverticuloscope (FEDD) and FED with cap (FEDC) had comparable technical success rate (99.6% vs. 100.0%) but FEDD had higher clinical success rate compared with FEDC (86.8% vs. 75.4%). FEDD had twice the risk of symptom recurrence than FEDC (16.5% vs. 9.5%). FEDD had a comparable bleeding risk to FEDC (3.3% vs. 4.0%) but a much lower perforation rate (2.3% vs. 10.3%). Upper esophageal sphincterotomy and adequate length of septotomy are the cornerstones of FED. FED can be considered a safe and efficacious treatment modality for patients with ZD.

Endoscopic submucosal dissection for early esophageal neoplasms using the stag beetle knife

AIM

To determine short- and long-term outcomes of endoscopic submucosal dissection (ESD) using the stag beetle (SB) knife, a scissor-shaped device.

METHODS

Seventy consecutive patients with 96 early esophageal neoplasms, who underwent ESD using a SB knife at Kure Medical Center and Chugoku Cancer Center, Japan, between April 2010 and August 2016, were retrospectively evaluated. Clinicopathological characteristics of lesions and procedural adverse events were assessed. Therapeutic success was evaluated on the basis of en bloc, histologically complete, and curative or non-curative resection rates. Overall and tumor-specific survival, local or distant recurrence, and 3- and 5-year cumulative overall metachronous cancer rates were also assessed.

RESULTS

Eligible patients had dysplasia/intraepithelial neoplasia (22%) or early cancers (squamous cell carcinoma, 78%). The median procedural time was 60 min and on average, the lesions measured 24 mm in diameter, yielding 33-mm tissue defects. The en bloc resection rate was 100%, with 95% and 81% of dissections deemed histologically complete and curative, respectively. All procedures were completed without accidental incisions/perforations or delayed bleeding. During follow-up (mean, 35 ± 23 mo), no local recurrences or metastases were observed. The 3- and 5-year survival rates were 83% and 70%, respectively, with corresponding rates of 85% and 75% for curative resections and 74% and 49% for non-curative resections. The 3- and 5-year cumulative rates of metachronous cancer in the patients with curative resections were 14% and 26%, respectively.

CONCLUSION

ESD procedures using the SB knife are feasible, safe, and effective for treating early esophageal neoplasms, yielding favorable short- and long-term outcomes.

Flexible robotic endoscopy: current and original devices

Two current major research topics concern the incorporation of flexible robotic endoscopy systems developed for natural-orifice translumenal endoscopic surgery (NOTES), primarily for the purpose of remote forceps operation, into endoscopic submucosal dissection (ESD) and other flexible endoscopic treatments and the use of robots for the manipulation of flexible endoscopes themselves with the aim of enabling the remote insertion of colonoscopes, etc. However, there are still many challenges that remain to be addressed; the ideal robotic endoscope has not yet been realized. This article reviews the ongoing developments and our own efforts in the area of flexible robotic endoscopy.

Feasibility of endoscopic submucosal dissection for cecal lesions

BACKGROUND

The treatment results of endoscopic submucosal dissection (ESD) for colorectal lesions have improved markedly, but some lesions remain difficult to treat. Hence the cecum is considered a technically challenging site for ESD. We examined the feasibility of ESD for cecal lesions.

METHODS

Among a total of 708 colorectal ESD performed in our hospital between March 2006 and December 2016, 549 procedures performed after April 2012 were studied, at a time when the techniques of ESD had stabilized and the procedure was covered by health insurance in Japan. Among 549 cases, 61 were cecal lesions and 488 were noncecal lesions. The treatment outcomes were analyzed.

RESULTS

For cecal lesions, the en bloc resection rate was 95.1%, R0 resection rate was 91.8%, perforation rate was 0%, delayed bleeding rate was 6.6%, median diameter of resected specimen was 32 mm (16-65 mm), median time of the procedure was 44 minutes (8-140 min). The corresponding results for noncecal lesions were 97.3%, 95.5%, 0.4%, 2.7%, 30 mm (10-109 mm), and 37 min (7-225 min). No significant differences were observed and the good treatment results were seen. When the outcomes were analyzed for cecal sites considered to be particularly challenging; proximity to appendiceal orifice, the ileocecal valve, and the bottom of cecum, the treatment results were not inferior to other sites.

CONCLUSIONS

ESD is safe and effective even for cecal lesions considered challenging to treat. ESD is feasible for cecal lesions.

Two electrosurgical endo-knives for endoscopic submucosal dissection of colorectal superficial neoplasms: a prospective randomized study

BACKGROUND AND STUDY AIMS

Few studies have directly compared endo-knives for endoscopic submucosal dissection (ESD) in humans. We compared the performances of the Mucosectom2 and SB knife Jr.

PATIENTS AND METHODS

 Two trainee endoscopists performed ESD of 36 lesions in this prospective, randomized controlled trial. Mucosal incision with a 1.5-mm Dual knife and submucosal dissection using the Mucosectom2 were performed in 1 group. Mucosal incision with a 1.5-mm Dual knife and submucosal dissection with a SB knife Jr. were performed in the other group. The primary outcome was the ESD procedure time. Secondary outcomes were total procedure time, self-completion rates, and adverse events.

RESULTS

ESD time in Mucosectom2 patients was not significantly shorter than in SB knife Jr. patients (57 ± 32 min vs. 61 ± 44 min, respectively; P  = 0.94). Total procedure time in Mucosectom2 patients was not significantly shorter than in SB knife Jr. patients (81 ± 42 min vs. 82 ± 51 min, respectively; P =  0.85). The trainee self-completion rate was slightly higher in SB knife Jr. patients than in Mucosectom2 patients, although the difference was not significant (94 % vs. 100 %, respectively; P  = 0.959). Fewer hemostatic procedures using the Coagrasper were performed in Mucosectom2 patients than in SB knife Jr. patients, although the difference was not significant (0.62 vs. 0.7, respectively; P  = 0.432).

CONCLUSIONS

 Mucosectom2 and SB knife Jr. did not significantly differ in performance for colorectal ESD to safely and reliably enhance ESD. Knife selection is not as important for learning colorectal ESD as patient- and lesion-related factors.

Peroral endoscopic myotomy using FlushKnife BT: a single-center series

BACKGROUND AND STUDY AIMS

Peroral endoscopic myotomy (POEM) is an evolving new treatment strategy for achalasia. Although several kinds of electrosurgical knives have been used in performing POEM, the best device has yet to be determined. The FlushKnife BT is a waterjet-emitting short needle-knife with a small ball tip (BT) that offers the potential to perform all aspects of POEM with a single device. In this study, we evaluated the safety and efficiency of the FlushKnife BT for POEM.

PATIENTS AND METHODS

 A total of 54 consecutive patients with achalasia and other spastic esophageal motility disorders, such as jackhammer esophagus or distal esophageal spasm, who underwent POEM between January 2016 and August 2016, were included in this retrospective study.

RESULTS

 The median operation time was 73.0 minutes (range 39 - 184 minutes). All procedures were completed using only the FlushKnife BT without changing to any other electrosurgical instrument. The median number of additional submucosal injections with an injection needle was 0 (range 0 - 1). Endoscopic vessel sealing was performed a mean of 3 times (range 0 - 7). The median number of bleeding episodes requiring treatment with hemostatic forceps was 0 (range 0 - 5). There were no significant adverse events. Seven of 52 patients (13.5 %) reported symptoms of gastroesophageal reflux disease such as heartburn or acid reflux at 3 month follow-up.

CONCLUSIONS

 The FlushKnife BT enabled POEM to be performed with very few device exchanges, either for re-injection or to control intraoperative bleeding. In this uncontrolled case series, the ability of the FlushKnife BT to perform nearly all aspects of the POEM procedure seems to make it particularly well suited to this procedure.

Scissor-type knife significantly improves self-completion rate of colorectal endoscopic submucosal dissection: Single-center prospective randomized trial

BACKGROUND AND AIM

Colorectal endoscopic submucosal dissection (C-ESD) is recognized as a difficult procedure. Recently, scissors-type knives were launched to reduce the difficulty of C-ESD. The aim of this study was to evaluate the efficacy and safety of the combined use of a scissors-type knife and a needle-type knife with a water-jet function (WJ needle-knife) for C-ESD compared with using the WJ needle-knife alone.

METHODS

This was a prospective randomized controlled trial in a referral center. Eighty-five patients with superficial colorectal neoplasms were enrolled and randomly assigned to undergo C-ESD using a WJ needle-knife alone (Flush group) or a scissor-type knife-supported WJ needle-knife (SB Jr group). Procedures were conducted by two supervised residents. Primary endpoint was self-completion rate by the residents.

RESULTS

Self-completion rate was 67% in the SB Jr group, which was significantly higher than that in the Flush group (39%, P = 0.01). Even after exclusion of four patients in the SB Jr group in whom C-ESD was completed using the WJ needle-knife alone, the self-completion rate was significantly higher (63% vs 39%; P = 0.03). Median procedure time among the self-completion cases did not differ significantly between the two groups (59 vs 51 min; P = 0.14). No fatal adverse events were observed in either group.

CONCLUSIONS

In this single-center phase II trial, scissor-type knife significantly improved residents' self-completion rate for C-ESD, with no increase in procedure time or adverse events. A multicenter trial would be warranted to confirm the validity of the present study.

Efficacy of a new hemostatic forceps during gastric endoscopic submucosal dissection: A prospective randomized controlled trial

BACKGROUND AND AIM

Currently, endoscopic submucosal dissection (ESD) is a widely accepted standard treatment for early gastric cancer, but one challenging aspect of ESD is hemostasis. We developed a new hemostatic forceps (FD-Y0007) with the aim of achieving more effective hemostasis and investigated the hemostatic ability of the FD-Y0007 during gastric ESD in humans.

METHODS

This study was a prospective randomized controlled trial, which was conducted at a cancer referral center. Sixty-six patients who were scheduled to undergo ESD were enrolled and randomly assigned to either the Coagrasper or the FD-Y0007, which was used for hemostasis throughout the case. The primary end point was the time required to obtain hemostasis, which was measured for the first episode of bleeding during each case.

RESULTS

Hemostasis time for the first bleeding episode during ESD was 73.0 s for the Coagrasper and 21.5 s for the FD-Y0007 (P < 0.001). When all episodes of bleeding were included, hemostasis time was 56.8 s in the Coagrasper group and 25.5 s in FD-Y0007group (P < 0.0001). The frequency of adverse events (perforation: 3.4% vs 7.1%; delayed bleeding: 0% vs 0%) was not significantly different between the two groups.

CONCLUSIONS

Compared with the Coagrasper, the FD-Y0007 efficiently reduces the hemostatic time during gastric ESD with no increase in adverse events.

Colorectal endoscopic submucosal dissection: a systematic review and meta-analysis

Background and study aims: Endoscopic submucosal dissection (ESD) is an advanced endoscopic technique that allows en-bloc resection of gastrointestinal tumor. We systematically review the medical literature in order to evaluate the safety and efficacy of colorectal ESD. Patients and methods: We performed a comprehensive literature search of MEDLINE, EMBASE, Ovid, CINAHL, and Cochrane for studies reporting on the clinical efficacy and safety profile of colorectal ESD. Results: Included in this study were 13833 tumors in 13603 patients (42 % female) who underwent colorectal ESD between 1998 and 2014. The R0 resection rate was 83 % (95 % CI, 80 - 86 %) with significant between-study heterogeneity (P < 0.001) which was partly explained by difference in continent (P = 0.004), study design (P = 0.04), duration of the procedure (P = 0.009), and, marginally, by average tumor size (P = 0.09). Endoscopic en bloc and curative resection rates were 92 % (95 % CI, 90 - 94 %) and 86 % (95 % CI, 80 - 90 %), respectively. The rates of immediate and delayed perforation were 4.2 % (95 % CI, 3.5 - 5.0 %) and 0.22 % (95 % CI, 0.11 - 0.46 %), respectively, while rates of immediate and delayed major bleeding were 0.75 % (95 % CI, 0.31 - 1.8 %) and 2.1 % (95 % CI, 1.6 - 2.6 %). After an average postoperative follow up of 19 months, the rate of tumor recurrence was 0.04 % (95 % CI, 0.01 - 0.31) among those with R0 resection and 3.6 % (95 % CI, 1.4 - 8.8 %) among those without R0 resection. Overall, irrespective of the resection status, recurrence rate was 1.0 % (95 % CI, 0.42 - 2.1 %). Conclusions: Our meta-analysis, the largest and most comprehensive assessment of colorectal ESD to date, showed that colorectal ESD is safe and effective for colorectal tumors and warrants consideration as first-line therapy when an expert operator is available.

Flexible endoscopic treatment for Zenker's diverticulum with the SB Knife. Preliminary results from a single-center experience

BACKGROUND AND AIM

Flexible endoscopic septum division is becoming a prominent treatment option for Zenker's diverticulum (ZD). Over the years, various techniques have been developed and many cutting tools have been tested with varying results. We report our experience with a recently designed, monopolar, rotating, scissor-shaped device (SB Knife).

METHODS

Data on 31 consecutive patients that underwent flexible endoscopic treatment for ZD with the use of the SB Knife were retrieved. Dysphagia, regurgitation, and respiratory symptom severity before the procedure were graded. Procedure duration, rate of complications, symptom changes after the procedure and rate of relapsing patients during follow up were recorded.

RESULTS

The procedure was carried out successfully in all patients. Median procedure time was 14 min. One case of late-onset bleeding developed 1 week after the procedure, and was managed endoscopically. A significant symptom improvement was achieved (dysphagia: median score <3, median score >0, P < 0.001; regurgitation: median score <2, median score >0, P < 0.001; respiratory symptoms: median score <2, median score >0, P = 0.009). Two patients had mild relapsing symptoms, respectively, after 4 and 9 months from the procedure but refused further treatment.

CONCLUSIONS

Endoscopic treatment of ZD using this new device is safe and efficient at short term follow up. No perforations were observed and there was a substantial reduction of symptoms after the treatment. Larger studies are needed to fully assess advantages of this new device for endoscopic treatment of ZD.

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.

Simplified magnetic anchor-guided endoscopic submucosal dissection in dogs (with videos)

BACKGROUND

Magnetic anchor-guided endoscopic submucosal dissection (MAG-ESD) was developed to reduce adverse events such as bleeding and perforation and to facilitate ESD. However, the external electromagnet required miniaturization to make it suitable for daily clinical practice.

OBJECTIVE

To evaluate the feasibility of simplified MAG-ESD using permanent magnets.

DESIGN

Case series.

SETTING

Nagoya University Hospital.

SUBJECTS

Beagle dogs.

INTERVENTIONS

The simplified MAG-ESD was performed on 10 representative areas of the stomachs of beagle dogs. The magnetic anchor consisted of an internal magnet attached to a hemoclip. The external and internal magnets were made from the rare earth neodymium.

MAIN OUTCOME MEASUREMENTS

The feasibility of countertraction with good visualization using simplified MAG-ESD. The rate of perforation, the time required for preparation, and attaching the magnetic anchor were also evaluated.

RESULTS

All lesions were successfully resected without perforation. The magnetic anchor could be controlled easily, and direct visualization was maintained by adequate counter traction. Preparing the magnetic anchor and grasping the mucosal edge using the hemoclip was easy and required a median of only 4 minutes (range, 2-7 minutes).

LIMITATIONS

Animal experiment, low number and lesion size.

CONCLUSIONS

This simplified MAG-ESD is feasible and allowed excellent visualization in the dog stomach. The feasibility of this system should be assessed in humans.

Retrospective study of technical aspects and complications of endoscopic submucosal dissection for large superficial colorectal tumors

BACKGROUND AND AIM

Colorectal endoscopic submucosal dissection (ESD) is widely carried out, but is still considered difficult. In 2010, a tumor size of ≥ 50 mm and less experience in colorectal ESD were reported as independent risk factors for complications such as perforation, delayed perforation and postoperative bleeding. In order to overcome such difficulties, we developed a scissors-type grasping device and reported the treatment results of a multicenter study. The aim of the present study was to investigate therapeutic outcomes of colorectal ESD of different tumor sizes.

METHODS

Group A (134 tumors): tumor size < 50 mm, and Group B (16 tumors): tumors ≥ 50 mm. All tumors were removed by ESD. We retrospectively evaluated the clinicopathological features of the tumors and the treatment results.

RESULTS

Age, sex, tumor location and histopathological diagnosis were not different between the two groups. Laterally spreading tumor non-granular type was more often observed in Group A (64/134, 47.8%) than in Group B (0/16, 0%). Procedure time was significantly longer in Group B (Group A: 38 min; Group B: 86 min, P < 0.01). However, procedure speed was significantly faster in Group B (Group A: 0.21 cm(2) /min; Group B: 0.37 cm(2) /min, P < 0.01). No complications were observed in either group. The en bloc resection rate, en bloc R0 resection rate, and en bloc curative resection rate were similar between the groups with no significant differences.

CONCLUSIONS

Procedure speed for Group B was faster than that for Group A. Group B was treated as safely as Group A.

Endoscopic therapy for early gastric cancer: Standard techniques and recent advances in ESD

The technique of endoscopic submucosal dissection (ESD) is now a well-known endoscopic therapy for early gastric cancer. ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precision of histologic diagnosis and can also reduce the recurrence rate. However, the drawback of ESD is its technical difficulty, and, consequently, it is associated with a high rate of complications, the need for advanced endoscopic techniques, and a lengthy procedure time. Various advances in the devices and techniques used for ESD have contributed to overcoming these drawbacks.

Predictors of incomplete resection and perforation associated with endoscopic submucosal dissection for colorectal tumors

BACKGROUND AND OBJECTIVE

Colorectal endoscopic submucosal dissection (ESD) is technically challenging. Our aim was to identify predictors of incomplete resection and perforation in colorectal ESD.

DESIGN

Retrospective study.

SETTING

Academic Japanese endoscopy unit.

PATIENTS AND MAIN OUTCOME MEASUREMENTS

A total of 267 consecutive cases of colorectal tumors treated by ESD from May 2010 to February 2013 were analyzed. Predictors of incomplete resection and perforation, including lesion size, growth type, pathological diagnosis, use of hemostatic forceps, degree of fibrosis, history of biopsy, history of local endoscopic treatment, and endoscopic operability.

RESULTS

The incomplete resection rate was 4.1%. The perforation rate was 5.6%. Univariate analysis identified severe fibrosis (P = .032), submucosal (SM) deep (>1000 μm) invasion (P = .033) and poor endoscopic operability (P = .030) as predictors of incomplete resection, and severe fibrosis (P = .038), postendoscopic treatment (P = .016), and poor endoscopic operability (P = .012) as predictors of perforation. Multivariate analysis identified poor endoscopic operability and SM deep invasion as independent predictors of incomplete resection, and poor endoscopic operability and severe fibrosis as independent predictors of perforation. There was no adjustment of P values for multiple testing.

LIMITATION

A single-center study by a single colonoscopist. All statistical results should be taken as descriptive only.

CONCLUSIONS

Poor endoscopic operability and SM deep invasion were significant independent predictors of incomplete resections. Poor endoscopic operability and severe fibrosis were significant independent predictors of perforation. These features may provide helpful information when planning colorectal ESD.

Prevention and management of complications of and training for colorectal endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is reported to be an efficient treatment with a high rate of en bloc resection for large colorectal tumors in Japan and some other Western and Asian countries. ESD is considered less invasive than laparoscopic colectomy. However, ESD carries a higher risk of perforation than endoscopic mucosal resection (EMR). Various devices and training methods for colorectal ESD have been developed to solve the difficulties. In this review, we describe the complications of colorectal ESD and prevention of those complications. On the other hand, colorectal ESD is difficult for less-experienced endoscopists. The unique step-by-step ESD training system is performed in Japan. Additionally, appropriate training, including animal model training, for colorectal ESD should be acquired before working on clinical cases.

Warning for unprincipled colorectal endoscopic submucosal dissection: accurate diagnosis and reasonable treatment strategy

Piecemeal endoscopic mucosal resection (EMR) is generally indicated for laterally spreading tumors (LST) >2 cm in diameter. However, the segmentation of adenomatous parts does not affect the histopathological diagnosis and completeness of cure. Thus, possible indications for piecemeal EMR are both adenomatous homogenous-type granular-type LST (LST-G) and LST-G as carcinoma in adenoma without segmentalizing the carcinomatous part. Diagnosis of the pit pattern using magnifying endoscopy is essential for determining the correct treatment and setting segmentation borders. In contrast, endoscopic submucosal dissection (ESD) is indicated for lesions requiring endoscopic en bloc excision, as it is difficult to use the snare technique for en bloc excisions such as in non-granular-type LST (LST-NG), especially for the pseudodepressed type, tumors with a type VI pit pattern, shallow invasive submucosal carcinoma, largedepressed tumors and large elevated lesions, which are often malignant (e.g. nodular mixed-type LST-G). Other lesions, such as intramucosal tumor accompanied by submucosal fibrosis, induced by biopsy or peristalsis of the lesion; sporadic localized tumors that occur due to chronic inflammation, including ulcerative colitis; and local residual early carcinoma after endoscopic treatment, are also indications for ESD. In clinical practice, an efficient endoscopic treatment with segregation of ESD from piecemeal EMR should be carried out after a comprehensive evaluation of the completeness of cure, safety, clinical simplicity, and cost-benefit, based on an accurate preoperative diagnosis.

Indications, Knives, and Electric Current: What's the Best?

Endoscopic submucosal dissection (ESD) was developed to overcome the limitations of conventional endoscopic mucosal resection (EMR), and ESD has been also applied for large colorectal neoplasms. Since colorectal ESD is still associated with higher perforation rate, a longer procedure time, and increased technical difficulty, the indications should be strictly considered. Generally, colorectal tumors without deep submucosal invasion or minimal possibility of lymph node metastasis, for which en bloc resection using conventional EMR is difficult, are good candidates for colorectal ESD. The ideal knife for colorectal ESD should avoid making perforations but can make a clean cut of optimal depth at one time. The ideal current for ESD differs depending on the procedure used, the surgical devices used, the tissue to be dissected, and the operator's preference. Application of the optimal indications and improvements in the technical skill and surgical devices are required for easier and safer colorectal ESD.