Endoscopic submucosal dissection for colorectal tumors: technical difficulties and rate of perforation

Non-Curative Endoscopic Submucosal Dissection: Current Concepts, Pitfalls and Future Perspectives

Endoscopic submucosal dissection (ESD) is very effective for the treatment of digestive tract neoplasia. However, it is very demanding, with a long learning curve, and, therefore, a significant rate of non-curative resections is expected, considering lesion characteristics, location, and endoscopist experience. The management of patients after a non-curative ESD is not definitely established. It must consider patients' comorbidities and expected survival, as well as the morbidity and mortality of complementary treatments such as surgery, chemotherapy, or radiotherapy. On the other hand, there is a window of opportunity to offer those additional treatments to complete neoplastic treatment and give patients an oncological cure. This decision is sometimes difficult, since the diverse histological criteria that define a non-curative ESD do not have the same weight regarding residual risk and oncological progression. The prediction of residual lesion would be paramount to decide whether to refer patients to surgery; nowadays, this prediction is far from perfect, since most of the patients that undergo surgery due to a non-curative ESD do not have residual neoplasia in the surgical specimen. In this review, ESD curativeness and the management of non-curative ESDs performed for esophageal, gastric, and colorectal lesions will be addressed.

Prospective, randomized controlled study evaluating a double-balloon interventional endoscopic platform for colorectal endoscopic submucosal dissection (with video)

BACKGROUNDS AND AIMS

Endoscopic submucosal dissection (ESD) can be challenging and time-consuming. A double-balloon interventional platform (DBIP) was designed to assist with navigation, stabilization, traction, and device delivery during complex colorectal polypectomy. We compared traditional ESD (T-ESD) with DBIP-assisted ESD (DBIP-ESD) in a prospective, randomized trial.

METHODS

Patients with colorectal polyps ≥2 cm were randomly assigned (1:1) to DBIP-ESD or T-ESD. The primary study endpoint was the mean total procedure time difference between groups. Secondary endpoints were intraprocedural time points, en bloc resection rate, procedure cost, adverse events, and 3-month assessment. A sample size of 200 subjects for ≥80% power was calculated. Interim analysis for early study termination was planned at 70% enrollment if the primary endpoint was met (P ≤ .05).

RESULTS

One hundred forty-seven patients were enrolled between February 2019 and February 2020. Seven patients dropped out, and the interim analysis was performed on 140 patients (71 DBIP-ESD, 69 T-ESD). Demographics, comorbidities, and lesion size, location, and classification were similar between groups. The mean procedure time decreased with DBIP-ESD (88.6 ± 42.7 minutes) versus T-ESD (139.5 ± 83.2 minutes; difference of ∼51 minutes [36.5%]; P < .001], with procedural savings of $610.16 (11.4%) per patient after DBIP cost. The DBIP increased dissection speed by 49.0% (15.1 ± 8.0 vs 7.7 ± 6.6 cm2/h, P < .001). En bloc resection was superior with the addition of DBIP (97.2% vs 87.0%, P = .030). The mean navigation time with DBIP-ESD for sutured defect closure decreased by 7.7 minutes (P < .001). There were no adverse events in the DBIP-ESD group.

CONCLUSIONS

DBIP-ESD decreased the total procedure time, improved the en bloc resection rate, and facilitated sutured defect closure, making DBIP a promising and cost-effective tool to improve colorectal ESD adoption. (Clinical trial registration number: NCT03846609.).

Endoscopic suturing for mucosal defect closure following endoscopic submucosal dissection: Systematic review and meta-analysis

Background and study aims: Endoscopic submucosal dissection (ESD) is a minimally invasive and effective treatment for gastrointestinal lesions. It carries potential risks such as bleeding and perforation. This meta-analysis was conducted to assess the safety, effectiveness, and feasibility of endoscopic suturing, a promising technique for closing mucosal defects post-ESD. Methods: We reviewed several databases, including MEDLINE/PubMed, Cochrane Library, Web of Science, and Embase up to May 1,2023. We aimed at identifying original studies that provided insightful data on the use of endoscopic suturing in reducing complications post-ESD. Results: In our study, we evaluated 426 publications and included 10 studies involving a total of 284 patients. The pooled technical success rate of endoscopic suturing was 92.6% (95% confidence interval [CI] 0.88-0.96). The pooled rate for sustained closure of mucosal defects post-endoscopic submucosal dissection (ESD) was estimated to be 80.7% (95% CI 0.71-0.88). The pooled mean time required to perform the endoscopic suturing procedure was calculated to be 31.11 minutes (95% CI 16.01-46.21). Among the studies reviewed for the incidence of delayed perforation post-ESD, a singular event of perforation was documented, suggesting a minimal occurrence. The overall rate of delayed bleeding was 5.3% (95% CI 0.30-0.10). Within the subset of patients using antithrombotic drugs, our subgroup analysis identified a delayed bleeding event rate of 6.7% (95% CI 0.02-0.25). Conclusions: Our results underscore the potential of endoscopic suturing as a viable and efficient technique in managing mucosal defects following ESD, highlighting the need for further large, prospective research to corroborate these findings and concentrate on establishing standard methodologies.

Outcome and predictive factors for perforation in orthodontic rubber band-assisted endoscopic submucosal dissection of fibrotic colorectal lesions

Endoscopic submucosal dissection (ESD) of fibrotic colorectal lesions is difficult and has a high complication rate. There are only a few reports on the utility of orthodontic rubber band (ORB) traction in reducing the difficulty of this procedure. This study aimed to investigate the risk factors for perforation when applying ORB traction during ESD of fibrotic colorectal lesions. We continuously collected the clinical data of 119 patients with fibrotic colorectal lesions who underwent ESD with ORB and clip traction between January 2019 and January 2024. Possible risk factors for perforation were analyzed. The median ORB-ESD operative time was 40 (IQR 28-62) min, and the en bloc and R0 resection rates were 94.1% and 84.0%, respectively. Perforation occurred in 16 of 119 patients (13.4%). The lesion size, lesion at the right half of the colon or across an intestinal plica, the degree of fibrosis, operation time, and the surgeon's experience were associated with perforation during ORB-ESD (P < 0.05). Multivariate logistic regression analysis showed that lesions in the right colon (OR 9.027; 95% CI 1.807-45.098; P = 0.007) and those across an intestinal plica (OR 7.771; 95% CI 1.298-46.536; P = 0.025) were independent risk factors for perforation during ORB-ESD. ORB-ESD is an effective and feasible approach to treat fibrotic colorectal lesions. Adequate preoperative evaluation is required for lesions in the right colon and across intestinal plicas to mitigate the risk of perforation.

Ultra-minimally invasive endoscopic techniques and colorectal diseases: Current status and its future

Colorectal diseases are increasing due to altered lifestyle, genetic, and environmental factors. Colonoscopy plays an important role in diagnosis. Advances in colonoscope (ultrathin scope, magnetic scope, capsule) and technological gadgets (Balloon assisted scope, third eye retroscope, NaviAid G-EYE, dye-based chromoendoscopy, virtual chromoendoscopy, narrow band imaging, i-SCAN, etc.) have made colonoscopy more comfortable and efficient. Now in-vivo microscopy can be performed using confocal laser endomicroscopy, optical coherence tomography, spectroscopy, etc. Besides developments in diagnostic colonoscopy, therapeutic colonoscopy has improved to manage lower gastrointestinal tract bleeding, obstruction, perforations, resection polyps, and early colorectal cancers. The introduction of combined endo-laparoscopic surgery and robotic endoscopic surgery has made these interventions feasible. The role of artificial intelligence in the diagnosis and management of colorectal diseases is also increasing day by day. Hence, this article is to review cutting-edge developments in endoscopic principles for the management of colorectal diseases.

Randomized trial of gastric and colorectal endoscopic submucosal dissection defect closure comparing a novel through-the-scope suturing system with an over-the-scope suturing system (with video)

BACKGROUND AND AIMS

Mucosal closure adds time but reduces adverse events associated with endoscopic submucosal dissection (ESD). We aimed to assess the closure time (CT), technical success, and cost-effectiveness between a novel through-the-scope helix tack suture system (TTSS) and the over-the-scope suturing system (OTSS).

METHODS

In this single-center, prospective, randomized trial, all patients undergoing ESD with anticipated closure were randomized 1:1 to TTSS (study group) or OTSS (control group). Primary outcomes were CT and overall CT (OCT; CT + setup time). Secondary outcomes were rates of technical success, adverse events, and cost-effectiveness.

RESULTS

Forty patients were randomized to OTSS (n = 20) or TTSS (n = 20). OTSS and TTSS groups were similar with respect to age, gender, proportion of colorectal polyps, proximal colon polyps, and mean size of the resected specimen (40.9 mm vs 40.4 mm). The mean CT was 18.4 minutes for OTSS and 23.3 minutes for TTSS (P = .36). The mean OCT was 32 minutes for OTSS and 39.5 minutes for TTSS (P = .36). Closure with a primary device was successful in 17 cases (85%) with OTSS and 18 cases (90%) with TTSS (P = .63). No closure-related intraprocedural adverse events or delayed perforations were noted. Mean cost of closure was significantly lower in the TTSS group for lesions <35 mm (P = .008).

CONCLUSIONS

TTSS was not found to be superior to OTSS with respect to CT and technical and clinical success for closure of gastric and colorectal ESD defects. TTSS is more cost-effective for closure of lesions <35 mm. (Clinical trial registration number: NCT04925271.).

Does Prophylactic Closure Improve Outcomes After Colorectal Endoscopic Submucosal Dissection? A Systematic Review and Meta-analysis

BACKGROUND

Several studies have described prophylactic closure after endoscopic submucosal dissection (ESD) of colorectal lesions for improving postoperative outcomes. We reviewed the evidence on the impact of prophylactic closure after ESD.

METHODS

A literature search was conducted on PubMed, Embase, CENTRAL, and Web of Science by 2 reviewers independently for studies published up to July 9, 2023. All types of comparative studies were eligible.

RESULTS

Ten studies compared 939 patients undergoing prophylactic closure with 1074 controls. Three were randomized controlled trials (RCTs) while the rest were observational. Pooled data from all included studies showed that prophylactic closure resulted in reduced incidence of delayed bleeding after ESD [odds ratio (OR): 0.30; 95% CI: 0.15, 0.72; I2 =0%]. These results were significant only for observational studies but not for RCTs. Meta-analysis showed no significant difference in the risk of delayed perforation (OR: 0.55; 95% CI: 0.18, 1.70; I2 =0%) or post-ESD coagulation syndrome (PECS) (OR: 1.15; 95% CI: 0.41, 3.19; I2 =63%) between closure and nonclosure groups.

CONCLUSIONS

Observational data suggest that prophylactic closure of colorectal mucosal defects after ESD may reduce the risk of delayed bleeding. However, the results are not concurred by RCTs. Furthermore, there seems to be no impact of prophylactic closure on the risk of delayed perforation and PECS.

Risk of Residual Neoplasia after a Local-Risk Resection of Colorectal Lesions by Endoscopic Submucosal Dissection: A Multinational Study

Endoscopic submucosal dissection (ESD) in colorectal lesions is demanding, and a significant rate of non-curative procedures is expected. We aimed to assess the rate of residual lesion after a piecemeal ESD resection, or after an en bloc resection but with positive horizontal margins (local-risk resection-LocRR), for colorectal benign neoplasia. A retrospective multicenter analysis of consecutive colorectal ESDs was performed. Patients with LocRR ESDs for the treatment of benign colorectal lesions with at least one follow-up endoscopy were included. A cohort of en bloc resected lesions, with negative margins, was used as the control. A total of 2255 colorectal ESDs were reviewed; 352 of the ESDs were "non-curative". Among them, 209 were LocRR: 133 high-grade dysplasia and 76 low-grade dysplasia. Ten cases were excluded due to missing data. A total of 146 consecutive curative resections were retrieved for comparison. Compared to the "curative group", LocRRs were observed in lengthier procedures, with larger lesions, and in non-granular LSTs. Recurrence was higher in the LocRR group (16/199, 8% vs. 1/146, 0.7%; p = 0.002). However, statistical significance was lost when considering only en bloc resections with positive horizontal margins (p = 0.068). In conclusion, a higher rate of residual lesion was found after a piecemeal ESD resection, but not after an en bloc resection with positive horizontal margins.

Left colonic localization, non-granular morphology, and pit pattern independently predict submucosal fibrosis of naïve colorectal neoplasms before endoscopic submucosal dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) represents the method of choice for removal of large colorectal neoplasms with suspected submucosal invasion. Presence and degree of submucosal fibrosis increases ESD duration and technical complexity, reduces the rate of curative resection and reduces safety profile. The aim of the study was to identify pre-procedural predictive factors of submucosal fibrosis in naïve colorectal neoplasms and to assess the impact of fibrosis on technical and clinical ESD outcomes.

METHODS

All consecutive ESD performed between 2014 and 2021 were retrieved from a prospectively collected database. For each patient, pre-procedural, procedural, and post-procedural data were recorded. Logistic regression was used to identify pre-procedural predictive factors for submucosal fibrosis. The study was approved by Institutional Reviewer Board and registered on ClinicalTrials.gov (NCT04780256).

RESULTS

One hundred-74 neoplasms (46.6% rectum, 21.8% left colon, 31.6% right colon; size 34.9 ± 17.5 mm) from 169 patients (55.0% male; 69.5 ± 10.4-year-old) were included. 106 (60.9%) neoplasms were granular type laterally spreading tumor (LST-G), 42 (24.1%) non-granular (LST-NG), and 26 (14.9%) sessile; invasive pit pattern was observed in 90 (51.7%) lesions. No fibrosis (F0) mild (F1) and severe (F2) were observed in 62 (35.6%), 92 (52.9%), and 20 (11.5%), respectively. Left colonic localization [OR 3.23 (1.1-9.31)], LST-NG morphology [OR 5.84 (2.03-16.77)] and invasive pit pattern [OR 7.11 (3.11-16.23)] were independently correlated to submucosal fibrosis. Lower curative resection rate (59.8% vs. 93.5%, P < 0.001) was observed in case of fibrosis; the incidence of adverse events was higher in case of severe fibrosis (35.5%) compared to no (3.2%) and mild fibrosis (3.3%; P < 0.001). Procedure time was significantly impacted by presence and degree of fibrosis (P < 0.001).

CONCLUSIONS

Left colonic localization, LST-NG morphology, and invasive pit pattern are independent predictors of fibrosis, affecting technical and clinical ESD outcomes. Pre-procedural stratification is pivotal to estimate procedure time, required operator's experience and advanced dissection techniques. Cecinato P et al. Left colonic localization, non-granular morphology, and pit pattern independently predict submucosal fibrosis of colorectal neoplasms before endoscopic submucosal dissection. Surg Endosc. 2023.

Comparison of Needle Knife versus Scissors Forceps for Colorectal Endoscopic Submucosal Dissection: A Prospective Randomized Study

Background and Aim: To evaluate the efficacy and safety of a grasping-type knife, called Clutch Cutter (CC), for colorectal endoscopic submucosal dissection (C-ESD). Methods: This was a randomized prospective study. Patients who underwent C-ESD for colorectal neoplasms >20 mm and <50 mm in size were enrolled, dividing into two groups: ESD using needle type of dual knife alone (D-group) and circumferential incision using dual knife followed by submucosal dissection using CC (CC-group). The primary outcome was the self-completion rate. The secondary outcomes were intraoperative complication rate, procedure time, and en bloc resection rate. Results: A total of 45 patients were allocated to the D-group and 43 to the CC-group were allocated. The self-completion rate was higher in the CC-group (87% [39/45] vs. 98% [42/43]). All of the six patients with an incomplete procedure in the D-group were completely resected with CC use. The intraoperative complication rate was not significant in either group (D vs. CC: 2% vs. 0%). The mean procedure time was significantly shorter in the D-group than that in the CC-group (62.0 vs. 81.1 min; p = 0.0036). The en bloc resection rate was 100% in the D-group and 98% in the CC-group. Conclusions: While dual knife use is superior to CC in terms of time efficiency, the use of CC may be a safe and efficacious option for achieving complete C-ESD.

Risk Stratification of Endoscopic Submucosal Dissection in Colon Tumors

Background: Endoscopic submucosal dissection (ESD) is a technique proven effective in the treatment of early neoplastic lesions in the gastrointestinal tract. However, in the case of colon lesions, many doubts remain. The purpose of our study is to stratify the success rates of the ESD procedure in the colon. Materials and Methods: A retrospective analysis of 601 patients who underwent ESD procedure for colorectal neoplasm from 2016 to 2019 in Center of Bowel Treatment, Brzeziny, Poland. Excluding 335 rectal neoplasms, we selected 266 patients with lesions located in the colon. Results: Lesions located in the left colon were characterized by the statistically higher en bloc resection and success rate, compared with the right colon—87.76% vs. 73.95% (p = 0.004) and 83.67% vs. 69.75% (p = 0.007), respectively. The success rate was significantly lower in lesions with submucosal cancer, compared to low- and high-grade dysplasia (p < 0.001). Polyps located in the right colon were characterized by a slightly higher complication rate compared to the left colon, without statistical significance—13.45% vs. 9.52% (p = 0.315). Conclusions: Our results show that colonic ESD has a high success rate, especially in the left colon, with a low risk of complications, slightly higher than in the right colon.

Use of an endoscopic flexible grasper as a traction tool for excision of polyps: preclinical trial

Endoscopic submucosal dissection (ESD) is challenging in the right colon. Traction devices can make it technically easier. In this study, we evaluated a flexible grasper with articulating tip and elbow-like bending (IgE) through a double-balloon surgical platform (DESP), compared with an earlier generation grasper without elbow-like bending (Ig). The reach of Ig/IgE was investigated at eight locations using a synthetic colon within a 3D model. Using a fresh porcine colorectum, 4 cm pseudo-polyps were created at the posterior wall of the ascending colon. Fifty-four ESD procedures were performed using three techniques: standard ESD (STD), ESD using Ig (DESP + Ig), and ESD using IgE (DESP + IgE). IgE was able to reach the full circumference at all the locations, whereas the medial walls proximal to the descending colon were out of Ig’s reach. Compared with the STD, both DESP + Ig and DESP + IgE showed significantly shorter procedure time (STD vs. DESP + Ig vs. DESP + IgE = median 48.9 min vs. 38.6 vs. 29.9) and fewer injuries (1.5 vs. 0 vs. 0). Moreover, the DESP + IgE had a shorter procedure time than the DESP + Ig (p = 0.0025). The IgE with DESP increased instrument reach compared to Ig, and likely represented a traction tool for excision of large pseudo-polyps in the right colon.

Factors Associated with Fibrosis during Colorectal Endoscopic Submucosal Dissection: Does Pretreatment Biopsy Potentially Elicit Submucosal Fibrosis and Affect Endoscopic Submucosal Dissection Outcomes?

BACKGROUND

Submucosal fibrosis observed during colorectal endoscopic submucosal dissection (ESD) is an important factor related to incomplete resection. Biopsy is generally accepted as having the potential to elicit submucosal fibrosis, but few reports have presented definitive proof. This study investigated the relation between submucosal fibrosis and colorectal ESD outcomes and assessed factors related to fibrosis, including pretreatment biopsy.

METHODS

After reviewing 369 records of colorectal ESD performed between January 2011 and December 2016, we assessed the relation between fibrosis and ESD outcomes. Multiple logistic regression analysis revealed fibrosis risk factors.

RESULTS

Severe fibrosis was related significantly to ESD outcomes such as the mean procedure time (p < 0.001), en bloc resection rate (p < 0.001), and R0 resection rate (p = 0.011). Multivariate analyses indicated residual lesions (ORs 175.4, p < 0.001), pretreatment biopsy (ORs 8.30, p = 0.002), nongranular-type laterally spreading tumors (LST-NG; ORs 5.86, p = 0.025), and invasive carcinoma (ORs 5.83, p = 0.03) as independent risk factors of severe fibrosis. In each macroscopic type, LST-NG was more strongly related to fibrosis induced by pretreatment than granular-type laterally spreading tumors with adjust ORs of 50.8 and 4.69.

CONCLUSIONS

Pretreatment biopsy causes submucosal fibrosis resulting in prolonged procedure times and incomplete resection. These findings suggest important benefits of avoiding biopsy before ESD.

Outpatient ESD for challenging colorectal lesions: Is it feasible and safe for western countries?

Background and study aims  The need for hospital beds during the COVID-19 pandemic almost overwhelmed the health care systems all over the world. Therefore, elective non-life-saving procedures were postponed. We decided to perform all colorectal endoscopic mucosal dissections (ESDs) for challenging lesions as outpatient procedures, organizing an ad hoc path to management of any delayed post-procedural complications. The aim of the present study was to retrospectively evaluate the feasibility and safety of outpatient ESD for colorectal tumors. Patients and methods  From March 2020 to May 2020, outpatient colorectal ESDs were performed for 15 challenging lesions. We retrospectively investigated feasibility and safety of the procedures, rates of en bloc resection, and complications rates. Results  The mean age of the patients was 66.5 years and 40 % of the them were on antiplatelet/anticoagulation therapy. Median size of removed lesions was 45 mm (range 32-77) and 38 mm (range 24 to 55) Five patients (33 %) had rectal tumors extending to the dentate line and four (26.6 %) were recurrences on a scar of previous endoscopic or surgical local resections. All complications, such as bleeding or visible microperforation, were managed endoscopically and no delayed perforations occurred. One patient had fever (37.5 °C), while three patients complained of anal pain after ESD for a rectal tumor that extended to the dentate line (RTDL); all patients were managed conservatively. Conclusion  Outpatient colorectal ESD is feasible and safe for challenging lesions. It reduces costs of hospitalization but direct access to the endoscopy service to manage potential post-ESD complications should always be guaranteed.

A risk-prediction model for en bloc resection failure or perforation during endoscopic submucosal dissection of colorectal neoplasms

OBJECTIVES

Technical difficulties in colorectal endoscopic submucosal dissections (ESD) result in en bloc resection failure or perforation. This study aimed to develop and validate a risk score for predicting en bloc resection failure or perforation in ESD of colorectal neoplasms.

METHODS

This single-center observational study included 1133 colorectal neoplasms treated with ESD in a Japanese tertiary cancer center. With a derivation set (n = 716), we performed multiple logistic regression to identify significant risk factors for en bloc resection failure or perforation. Based on odds ratios, we developed a risk score, ranging from 0 to 10: 0-1 'low risk' (LR); 2-4 'moderate risk' (MR); and 5-10 'high risk' (HR). An independent validation set comprised prospectively enrolled subjects (n = 417) that underwent ESDs from January 2014 to August 2016. The performance of the risk score for predicting en bloc resection failure or perforation for each risk tier was evaluated.

RESULTS

The baseline incidences of en bloc resection failure or perforation were 14.5% and 5.5% in the derivation and validation sets, respectively. We identified the following significant risk factors: endoscopist experience, tumor location, morphology, scope operability, underlying fold, and fold convergence. In the validation set, the incidences of en bloc resection failure or perforation were 0% in the LR tier (n = 62; 14.8%), 2.3% in the MR tier (n = 293; 70.4%), and 25.8% in the HR tier (n = 62; 14.8%) (P < 0.001, Cochran-Armitage trend test).

CONCLUSIONS

A risk scoring system, which was developed and prospectively validated, can successfully estimate the incidence of en bloc resection failure or perforation.

EMR/ESD: Techniques, Complications, and Evidence

PURPOSE OF REVIEW

To discuss endoscopic resection techniques of early gastrointestinal malignancy. The review will focus on the indications and outcomes of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD).

RECENT FINDINGS

EMR is indicated for upper GI lesions less than 20 mm provided they can be easily lifted and have a low risk of submucosal invasion (SMI). ESD should be considered for esophageal and gastric lesions that are bulky, show intramucosal carcinoma, or have a risk of superficial submucosal invasion. With regard to colonic polyps, EMR is acceptable for the removal of large colonic polyps using a piecemeal technique. ESD can be reserved for rectal neuroendocrine tumors, fibrotic polyps, or polyps harboring early malignancy. In selected cases, particularly in lesions less than 2 cm in size, EMR can be safe and effective. For larger lesions or lesions with submucosal invasion, ESD is effective and curative. Choosing the best approach can be tailored for each patient depending on lesion size, pathology, and availability of local expertise.

Safety and histologic outcomes of endoscopic submucosal dissection with a novel articulating knife for esophageal neoplasia

BACKGROUND AND AIMS

Treatment of large esophageal neoplasia is gradually evolving from piecemeal to en bloc resections. Endoscopic submucosal dissection (ESD) is known to achieve more complete resections than piecemeal EMR for large lesions, yet it remains underused in the West because of technical and safety concerns with traditional electrosurgical knives. We aimed to evaluate a novel endoscopic articulating knife used with ESD (ESD-AR) to determine its safety and efficacy for large esophageal neoplasms in comparison with EMR.

METHODS

We retrospectively studied clinically indicated cases of ESD-AR and EMR for esophageal lesions that were 15 mm or greater. All EMR cases had at least 3 simultaneous EMRs to adequately compare resection area. Rates of perforation, GI bleeding, technical performance, and pre- and postendoscopic resection diagnoses were evaluated.

RESULTS

Seventy-two ESD-AR and 72 widespread EMR cases were evaluated for Barrett's esophagus (56%), adenocarcinoma (36%), squamous nodularity (2%), and squamous cell carcinoma (6%). There were no statistical differences in age, sex, Barrett's esophagus length, and lesion or resection size between the 2 groups. No perforations occurred. Two adverse events were recorded with ESD-AR and none with EMR (3% vs 0%, P = .50); these were associated with anticoagulation use (P = .04) and greater resection area (P = .02). There were more upgraded diagnoses post-ESD versus EMR (27% vs 12%, P = .05).

CONCLUSIONS

ESD-AR by an experienced endoscopist has a comparable safety profile with widespread EMR for large esophageal neoplasia and may have advantages for diagnostic staging.

A reel mechanism-based robotic colonoscope with high safety and maneuverability

BACKGROUND

At present, the colonoscopy is the most common method of screening for colorectal cancer. However, endoscopists still encounter difficulties with intubation, primarily due to the structural diversity (e.g., path, shape, and size) and viscoelasticity of the colon. Therefore, well-trained, skillful operators are required to overcome these factors and operate colonoscopes without harming patients.

OBJECTIVES

In our previous work, we presented a reel mechanism-based robotic colonoscope designed to mitigate the difficulties of conventional colonoscopies. Although we reported excellent mobile performance with respect to the robot, we did not provide an in-depth discussion concerning patient safety. Therefore, in this article, we propose a method of improving robot safety, and this is verified by investigating the static and dynamic forces acting on the colon. In addition, the maneuverability and safety of the robot in the in vitro condition are evaluated.

METHODS

The safety solution is provided by covering the robot's legs with silicone. To evaluate the results, the reaction force according to leg deformation is measured. Then, the force transmitted to the colon is also measured when the robot moves through various environments. Finally, a mobility test on an excised porcine colon is performed to simultaneously verify the robot's maneuverability and safety.

RESULTS

We verify that the static and dynamic force acting on the colon is less than the burst force of a human colon. In addition, the maneuverability of the robotic colonoscope shows reliable locomotion performance even with the soft material covering the legs; it has forward velocities of 9.552 ± 1.940 mm/s on a flat path.

CONCLUSION

Owing to the reliable locomotion mechanism with the safety-securing silicone, the robot achieves high and reliable maneuverability without any scratches or perforations to the porcine colon.

Facilitating endoscopic submucosal dissection: double balloon endolumenal platform significantly improves dissection time compared with conventional technique (with video)

BACKGROUND

Flexible endoscopes ability to manipulate the intestinal environment is limited. As a result, complex endolumenal procedures are often technically demanding and result in long procedure times, impacting institutional resources. Single- and double-balloon add-on endoscopic devices have been employed throughout the GI tract to facilitate tissue control e.g., small bowel enteroscopy, with recent reports suggesting a possible colonic utility for complex procedures e.g., ESD. Our objective was to objectively analyze the efficacy of a new double-balloon device in performing ESD.

METHODS

Ex vivo-12 simulated colonic lesions were created in porcine rectum using a standard 40 mm diameter template. Two categories were evaluated, standard cap technique ESD and double-balloon assisted ESD with retraction (ESD-R). Cases were performed sequentially. In vivo-Six, 40 mm lesion ESD-R's were performed in a porcine model. The primary outcomes of this study were total procedure and dissection times.

RESULTS

In ex vivo studies, the median total procedure time with the double-balloon platform was significantly shorter than the traditional ESD technique (29 ± 18 vs. 57 ± 21 min, p = 0.03). In the in vivo studies, lesions were successfully removed in a mean time of 48 min, with a dissection time of 20 min with no significant complications. Balloon-clip retraction and specimen retrieval capabilities were used in all double-balloon assisted cases. After 6 cases, times were significantly shorter (ex vivo 47 vs. 17 min; in vivo 57 vs. 27 min).

CONCLUSIONS

We have demonstrated the development of a unique technical ESD method facilitated by a new double-balloon device. Ex and in vivo investigation demonstrated superiority of ESD-R over the conventional ex vivo method. The DB device provided increased stability, improved visualization and tissue traction, which significantly reduced dissection time. Such an approach may increase safety, improve patient outcomes, and may prevent unnecessary surgeries for benign conditions.

Pure Well-Differentiated Adenocarcinoma Is a Safe Factor for Lymph Node Metastasis in T1 and T2 Colorectal Cancer: A Pilot Study

BACKGROUND AND AIMS

Various risk factors for lymph node metastasis (LNM) have been reported in colorectal T1 cancers. However, the factors available are insufficient for predicting LNM. We therefore investigated the utility of the new histological factor "pure well-differentiated adenocarcinoma" (PWDA) as a safe factor for predicting LNM in T1 and T2 cancers.

MATERIALS AND METHODS

We reviewed 115 T2 cancers and 202 T1 cancers in patients who underwent surgical resection in our center. We investigated the rates of LNM among various clinicopathological factors, including PWDA. PWDA was defined as a lesion comprising only well-differentiated adenocarcinoma. The consistency of the diagnosis of PWDA was evaluated among two pathologists. In addition, 72 T1 cancers with LNM from 8 related hospitals over 10 years (2008-2017) were also analyzed.

RESULTS

The rates of LNM and PWDA were 23.5% and 20.0%, respectively, in T2 cancers. Significant differences were noted between patients with and without LNM regarding lymphatic invasion (81.5% vs. 36.4%, p < 0.001), poor histology (51.9% vs. 19.3%, p = 0.008), and PWDA (3.7% vs. 25.0%, p = 0.015). The rates of LNM and PWDA were 8.4% and 36.1%, respectively, in T1 cancers. Regarding the 73 PWDA cases and 129 non-PWDA cases, the rates of LNM were 0.0% and 13.2%, respectively (p < 0.001). Among the 97 cases with lymphatic or venous invasion, the rates of LNM in 29 PWDA cases and 68 non-PWDA were 0% and 14.7%, respectively (p = 0.029). The agreement of the two pathologists for the diagnosis of PWDA was acceptable (kappa value > 0.5). A multicenter review showed no cases of PWDA among 72 T1 cancers with LNM.

CONCLUSIONS

PWDA is considered to be a safe factor for LNM in T1 cancer.

The efficacy of the pocket-creation method for cases with severe fibrosis in colorectal endoscopic submucosal dissection

BACKGROUND AND STUDY AIMS

 Severe fibrosis poses a challenge in colorectal endoscopic submucosal dissection (ESD). Recently, the pocket-creation method (PCM) has been developed for overcoming various difficulties of ESD. A specific tapered hood is used for adequate traction in the PCM, and endoscopic operability becomes stable in the pocket. In this study, we investigated the efficacy of the PCM in ESD for cases with severe fibrosis.

PATIENTS AND METHODS

We retrospectively reviewed 1000 consecutive colorectal ESD cases (April 2006 to January 2017). Since 2016, the PCM was performed in 58 cases. The indications for ESD included (1) tumors ≥ 20 mm in size diagnosed as intramucosal cancer or high-grade dysplasia and part of T1a cancer using magnifying endoscopic examinations and (2) tumors that appeared impossible to resect with endoscopic mucosal resection because of suspected fibrosis. We identified 120 cases with severe fibrosis and compared them to cases without severe fibrosis. Additionally, the 120 severe fibrosis cases were divided into the PCM and non-PCM groups. En bloc resection, procedure time, discontinuation, and complications were analyzed between these 2 groups.

RESULTS

 Among all 1000 ESDs, severe fibrosis and discontinuation rates were 12.0 % (120 cases) and 1.8 % (18 cases), respectively. Regarding the comparison between cases with severe fibrosis and with no severe fibrosis, there were significant differences about en bloc resection rate (78.3 % vs. 95.7 %, P  < 0.001), discontinuance rate (12.5 % vs. 0.3 %, P  < 0.001), and perforation rate (8.3 % vs. 2.6 %, P  = 0.001). Among the 120 cases with severe fibrosis, 21 and 99 cases were in the PCM and non-PCM groups, respectively. The PCM group had a higher en bloc resection rate (95.2 vs. 74.7, P  =  0.03), a shorter mean procedure time (min) (79.6 ± 26.5 vs. 118.8 ± 71.0, P  = 0.001), and no cases of discontinuation. An analysis of the interobserver agreement for the diagnosis of severe fibrosis among the 3 endoscopists showed kappa values of > 0.6.

CONCLUSIONS

 In cases with severe fibrosis, the PCM with ESD improved en bloc resection rates and shortened the procedure time compared to the conventional non-PCM method. Additionally, the PCM reduced the discontinuation rate.

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.

Efficacy of a Novel Narrow Knife with Water Jet Function for Colorectal Endoscopic Submucosal Dissection

BACKGROUNDS

With respect to the knife's design in colorectal endoscopic submucosal dissection (ESD), diameter, water jet function, and electric power are important because these relate to efficient dissection. In this study, we analyzed a novel, narrow ball tip-typed ESD knife with water jet function (Flush knife BT-S, diameter: 2.2 mm, length: 2000 mm, Fujifilm Co., Tokyo, Japan) compared to a regular diameter knife (Flush knife BT, diameter: 2.6 mm, length: 1800 mm).

METHODS

In laboratory and clinical research, electric power, knife insertion time, vacuum/suction amount with knife in the endoscopic channel, and water jet function were analyzed. We used a knife 2.0 mm long for BT-S and BT knives.

RESULTS

The BT-S showed faster mean knife insertion time (sec) and better vacuum amount (ml/min) compared to the BT (insertion time: 16.7 versus 21.6, p < 0.001, vacuum amount: 38.0 versus 14.0, p < 0.01). Additionally, the water jet function of the BT-S was not inferior. In 39 colorectal ESD cases in two institutions, there were mean 4.7 times (range: 1-28) of knife insertion. Suction under knife happened 59% (23/39) and suction of fluid could be done in 100%.

CONCLUSIONS

Our study showed that the narrow knife allows significantly faster knife insertion, better vacuum function, and effective clinical results.

Colorectal endoscopic submucosal dissection (ESD)

Endoscopic submucosal dissection (ESD) is an interventional procedure for en-bloc resection of gastrointestinal lesions. ESD is a challenging and can involve a reasonable degree of risk, therefore case selection is of crucial importance, especially in the colo-rectum. This procedure should be mainly used for dissection of lesions when there is a high suspicion of superficial malignant invasion; several classifications have been proposed in order to better identify lesions suitable for ESD. However, case selection is still an issue, since only about 8-10% of dissected lesions are superficially invading cancer and most of cases involve benign or massively invading cancer. In addition, significant differences have been reported between Asian and Western countries in regard to main outcomes, and therefore measures should be adopted as soon as possible to reduce this discrepancy.

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.

Histopathological analysis of cold snare polypectomy and its indication for colorectal polyps 10-14 mm in diameter

BACKGROUND AND AIM

Cold snare polypectomy (CSP) is commonly used for treating colorectal polyps <10 mm in diameter. We evaluated the analysis and safety of CSP for larger polyps.

METHODS

We retrospectively analyzed 1006 colorectal polyps resected with CSP. Indication for CSP was polyps 2-14 mm that were diagnosed as benign neoplastic polyp by magnifying endoscopy. Various clinicopathological characteristics were analyzed. Multivariate analyses were used to determine the independent risk factors for failure of complete CSP resection. With respect to polyp size, we compared the therapeutic outcomes between polyps <10 mm and ≥10 mm. Additionally, the presence of muscularis mucosa in resected specimens was analyzed.

RESULTS

Rates of en bloc resection and postoperative hemorrhage were 98.8% and 0.1%, respectively. Seven hundred and ninety-one neoplastic lesions were analyzed and negative margins were found in 70.5% of the lesions, Multivariate analysis showed that non-polypoid morphology, histology of intramucosal cancer + high-grade adenoma and sessile serrated adenoma and polyp were significant factors for incomplete resection. With respect to the difference between lesions ≥10 mm than in those <10 mm, rates of cancer and positive/unclear margins were significantly higher (5.0% vs 0.9%, P < 0.001; 40.6% vs 27.7%, P = 0.007) in the ≥10 mm with rates of postoperative hemorrhage not significantly different (0.8% vs 0.0%). Additionally, the loss of muscularis mucosa was found in 27.8% of all lesions.

CONCLUSION

CSP is a safe procedure for polyps 2-14 mm. However, CSP has limitations in terms of the histopathological margin and loss of muscularis mucosa in specimens.

Endoscopic submucosal dissection for laterally spreading tumors involving the appendiceal orifice

BACKGROUND

Since the endoscopic resection of laterally spreading tumors (LSTs) involving the appendiceal orifice remains technically difficult, such lesions are usually treated by surgical resection. However, with recent advances in endoscopic devices, endoscopic submucosal dissection (ESD) has become feasible and may be safely performed even for lesions involving the appendiceal orifice. Therefore, in order to assess the validity of endoscopic treatment for such lesions, we retrospectively evaluated the safety and efficacy of ESD.

METHODS

A total of 30 patients with LSTs extending to within 10 mm of the appendiceal orifice (Group AO) and 122 patients with cecal LSTs located away from the appendiceal orifice (Group C) who were treated between December 2011 and September 2015 were retrospectively enrolled in the present study. The indications for ESD were determined by the preoperative endoscopic diagnosis made on the basis of Kudo's pit pattern classification. Based on these preoperative endoscopic diagnoses, 8 of the 30 enrolled patients underwent surgical resection as the initial treatment, because the tumor showed deep invasion beyond the orifice and/or a VN pit pattern was visible. The treatment outcomes (en bloc R0 resection rates, tumor size, procedure time, and complication rates) were compared between the two groups.

RESULTS

The sensitivity and specificity for the cancer diagnosis were 81.8 and 94.7%, respectively. There was no significant difference in the en bloc R0 resection rate between Group AO and Group C (90.9 vs. 95.9%, P = 0.23). Furthermore, there were also no differences in the mean tumor size (30.0 ± 20.8 vs. 34.9 ± 14.5 mm, P = 0.17) or mean OR time (55.0 ± 39.2 vs. 58.9 ± 48.2 min P = 0.72) between the two groups. One case from Group AO (4.5%) was complicated by a perforation, which was successfully managed endoscopically.

CONCLUSIONS

Although proficiency in endoscopic techniques is required, our results indicate that LSTs involving the appendiceal orifice can be successfully treated by ESD.

Tips for safety in endoscopic submucosal dissection for colorectal tumors

In Japan, endoscopic submucosal dissection (ESD) becomes one of standard therapies for large colorectal tumors. Recently, the efficacy of ESD has been reported all over the world. However, it is still difficult even for Japanese experts in some situations. Right-sided location, large tumor size, high degree of fibrosis, difficult manipulation is related with the difficulty. However, improvements on ESD devices, suitable strategies, and increase of operators' experiences enable us to solve these problems. In this chapter, we introduce recent topics about various difficult factors of colorectal ESD and the tips such as strategy, devices, injection, and traction method [Pocket-creation method (PCM) etc.].

Safety and Efficacy of a Same-Day Low-Volume 1 L PEG Bowel Preparation in Colonoscopy for the Elderly People and People with Renal Dysfunction

INTRODUCTION

A same-day low-volume 1 L polyethylene glycol (PEG) for bowel preparation before colonoscopy was developed to improve patients' compliance. We aimed to evaluate the efficacy and safety of this regimen especially for the elderly and patients with renal dysfunction.

METHODS

All consecutive patients who underwent colonoscopy in our center from November 2014 to September 2015 were included. Patients undertook a low-residue diet with 10 mL sodium picosulfate 1 day before colonoscopy. Subsequently, they had 1 L low-volume PEG (MoviPrep) and 0.5 L water 4 h before the examination. Clinical outcomes, including cleansing level using the Boston bowel preparation score (BBPS), in the elderly and special-elderly (65-79 and ≥80 years old) were analyzed and compared with the non-elderly (18-64 years old). Additionally, patients with renal dysfunction were analyzed with respect to both complications and changes in blood parameters.

RESULTS

A total of 5427 patients (mean age: 64.5 ± 13.8) were analyzed. The rate of BBPS ≥ 6 in the elderly (2761 patients), special-elderly (565 patients), and non-elderly (2101 patients) was 94.1, 91.8, and 94.6 %, respectively. In the special-elderly, the rate of renal dysfunction was 14.8 %, and no severe complications were detected after colonoscopy. Additionally, there were no severe complications in 86 patients with renal dysfunction, though elevation of hematocrit was shown after intake of 1 L PEG (before, 36.7 ± 6.1 vs. after, 39.0 ± 5.7, P = 0.006).

CONCLUSIONS

Our study shows the safety and efficacy of same-day low-volume 1 L PEG bowel preparation in colonoscopy for the elderly and patients with renal dysfunction.

Complications of endoscopic polypectomy, endoscopic mucosal resection and endoscopic submucosal dissection in the colon

Endoscopic resection (ER), including endoscopic polypectomy (EP), endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are used to remove superficial neoplasms from the colon. Snare resection is used for EP and EMR, whereas endoscopic knives are used to perform dissection in the submucosal space in ESD. 80-90% colonic polyps are <10 millimetres (mm) and are effectively managed by conventional EP. Increasingly cold snare polypectomy is preferred. Large laterally spreading lesions (LSLs) and sessile polyps ≥20 mm are primarily removed by EMR. ESD may be used when superficial invasive disease is suspected and for some LSLs, particularly non-granular subtypes. Resection of colonic lesions by ER is associated with a small but definite incidence of significant complications, most commonly bleeding and perforation. This review discusses complications of ER with a particular focus on their prevention, early recognition and management. In many cases, complications from all three procedures share similar mechanisms and management principles and these are described at the start of each section, followed by a description of specific aspects for individual procedures.

Prediction model and risk score for perforation in patients undergoing colorectal endoscopic submucosal dissection

BACKGROUND AND AIMS

Perforation is the adverse event of greatest concern during colorectal endoscopic submucosal dissection (ESD). Accurate risk prediction of perforation may enable prevention strategies and selection of the most efficient therapeutic option. This study aimed to develop and validate a risk prediction model for ESD-induced perforation.

METHODS

A multicenter cross-sectional study was performed on 2046 patients who underwent colorectal ESD at 9 Korean ESD Study Group-affiliated hospitals. The enrolled patients were randomly divided into either a derivation set or a validation set. In the derivation set, a prediction score was constructed to assess the risk of perforation using preoperative and procedural-related predictors selected via logistic regression. Discrimination and calibration of the prediction model was assessed using the validation set.

RESULTS

An ESD-induced perforation occurred in 135 patients (6.6%). In the derivation set, multivariate logistic regression identified endoscopist experience (≥50 ESDs: odds ratio [OR] = 0.59; 95% confidence interval [CI], 0.35-1.00), tumor size (+1-cm increments: OR = 1.39; 95% CI, 1.19-1.62), colonic location (OR = 2.20; 95% CI, 1.24-3.89), and submucosal fibrosis (OR = 2.00; 95% CI, 1.04-3.87) as predictive factors (C-statistic = 0.678; 95% CI, 0.617-0.739). In the validation set, the model showed good discrimination (C-statistic = 0.675; 95% CI, 0.615-0.735) and calibration (P = .635). When a simplified weighted scoring system based on the OR was used, risk of perforation ranged from 4.1% (95% CI, 2.8%-5.9%) in the low-risk group (score ≤4) to 11.6% (95% CI, 8.5%-15.6%) in the high-risk group (score >4).

CONCLUSIONS

This study developed and internally validated a score consisting of simple clinical factors to estimate the risk of colorectal ESD-induced perforation. This score can be used to identify patients at high risk before colorectal ESD.

Clinical usefulness of a single-use splinting tube for poor endoscope operability in deep colonic endoscopic submucosal dissection

BACKGROUND AND STUDY AIMS

Poor endoscope operability remains a significant challenge during colorectal endoscopic submucosal dissection (ESD). We retrospectively evaluated the experience and clinical usefulness of a new single-use splinting tube in deep colonic ESD in the setting of poor scope operability.

PATIENTS AND METHODS

Among 691 patients with colorectal tumors treated with ESD at Hiroshima University Hospital between November 2009 and July 2015, we analyzed 20 consecutive patients who underwent deep colonic ESD using a single-use splinting tube because of poor scope operability. Poor operability was defined as paradoxical movement of the endoscope, poor control with adhesions, and lesion motion with heartbeat or breathing. Technical and clinical success rates and adverse events were assessed.

RESULTS

Paradoxical movement and poor control with adhesions were improved in all cases using the single-use splinting tube. The en bloc resection rate was 95 % (19/20) and histological en bloc resection rate was 100 % (20/20). There were no complications related to use of the splinting tube.

CONCLUSIONS

Use of a single-use splinting tube helped to overcome poor scope operability in deep colonic ESD.

Meta-analysis comparing differing methods of endoscopic therapy for colorectal lesions

AIM: To compare the outcomes of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) of colorectal lesions.

METHODS: An electronic systematic literature search of four computerized databases was performed in July 2014 identifying studies reporting the outcomes of colorectal ESD and EMR. The primary outcome measures were en-bloc resection rate, endoscopic clearance rate and lesion recurrence rate of the patients followed up. The secondary outcome was the complication rate (including bleeding, perforation and surgery post EMR or ESD rate). Statistical pooling and random effects modelling of the studies calculating risk difference, heterogeneity and assessment of bias and quality were performed.

RESULTS: Six observational studies reporting the outcomes of 1324 procedures were included. The en-bloc resection rate was 50% higher in the ESD group than in the EMR group (95%CI: 0.17-0.83, P < 0.0001, I² = 99.7%). Endoscopic clearance rates were also significantly higher in the ESD group (95%CI: -0.06-0.02, P < 0.0001, I² = 92.5%). The perforation rate was 7% higher in the ESD group than the EMR group (95%CI: 0.05-0.09, P > 0.05, I² = 41.1%) and the rate of recurrence was 50% higher in the EMR group than in the ESD group (95%CI: 0.20-0.79, P < 0.001, I² = 99.5%). Heterogeneity remained consistent when subgroup analysis of high quality studies was performed (with the exception of piecemeal resection rate), and overall effect sizes remained unchanged for all outcomes.

CONCLUSION: ESD demonstrates higher en-bloc resection rates and lower recurrence rates compared to colorectal EMR. Differences in outcomes may benefit from increased assessment through well-designed comparative studies.

Endoscopic submucosal dissection and its potential role in the management of early colorectal neoplasia in UK

In Europe, colorectal cancer is the most common newly diagnosed cancer and the second most common cause of cancer deaths, accounting for approximately 436 000 incident cases and 212 000 deaths in 2008. National screening programmes will increase the number of early (pT1) cancers detected. pT1 cancers are those showing invasion through the muscularis mucosae into the submucosa but not into the muscularis propria. Microstaging of pT1 cancer is crucial in predicting those cases less likely to cause nodal disease and that will be cured with endoscopic resection alone. The submucosal extent and other histological features predict the risk of nodal disease, and for this reason, en bloc resection is highly desirable. Endoscopic submucosal dissection enables en bloc resection of mucosal and submucosal disease and could reduce the need for surgery in some cases by definitive initial resection.

High incidence of metachronous advanced adenoma and cancer after endoscopic resection of colon polyps ≥20 mm in size

BACKGROUND AND AIM

There are limited studies on incidence rates of metachronous neoplastic lesions after resecting large colorectal polyps. In the present study, we analyzed metachronous lesions after endoscopic resection of colorectal polyps ≥20 mm in size.

METHODS

We retrospectively analyzed consecutive patients who underwent endoscopic resection of polyps from 2006 to 2013 at two affiliated hospitals. All patients underwent at least two total colonoscopies before follow up to ensure minimal missed polyps. Only patients who had follow-up colonoscopy annually after resection were recruited. We separated patients according to size of polyp resected; there were 239 patients in the ≥20-mm group and 330 patients in the <20-mm group. Clinical characteristics and cumulative rates of metachronous advanced adenoma and cancer in both groups were analyzed. Advanced adenoma was defined as a neoplastic lesion ≥10 mm in size and adenoma with a villous component.

RESULTS

Cumulative rate of development of metachronous advanced adenoma and cancer in the ≥20-mm group was significantly higher than in the <20-mm group (22.9% vs. 9.5%, P < 0.001) at 36 months. There was also more development of small polyps 5-9 mm in the ≥20-mm group than in the <20-mm group (45.2% vs. 28.8%, P < 0.001). With respect to metachronous lesions, there were more right-sided colonic lesions in the ≥20-mm group than in the <20-mm group (78.8% vs. 50.0%, P = 0.015).

CONCLUSION

High incidence rates of development of metachronous neoplastic lesions were detected after resection of colorectal polyps ≥20 mm in size.

Colorectal endoscopic submucosal dissection (ESD) performed by experienced endoscopists with limited experience in gastric ESD

PURPOSE

Since colorectal endoscopic submucosal dissection (ESD) requires higher-level skills than endoscopic mucosal resection (EMR), it is recommended to acquire sufficient experience in gastric ESD prior to attempting colorectal ESD. We evaluated the ability of experienced endoscopists with limited experience in gastric ESD to perform colorectal ESD.

METHODS

We retrospectively reviewed 120 colorectal ESDs performed by two endoscopists who had expertise in colonoscopy and colorectal EMR but experience of fewer than five gastric ESDs. Main outcomes were the en bloc resection rate with tumor-free margins (R0 resection rate) and adverse events rate. Using only clinical characteristics prior to ESD, we also identified factors affecting outcomes.

RESULTS

A total of 113 patients (94.2 %) received en bloc resection, and the R0 resection rate was 80.0 % (96/120). Perforation and postoperative hemorrhage occurred in eight (6.7 %) and two (1.7 %) patients, respectively. Dividing the 120 cases into three learning phases, R0 resection and perforation rates improved from 77.5 % (31/40) and 12.5 % (5/40) in phase 1 to 85.0 % (34/40) and 2.5 % (1/40) in phase 3, respectively. Multivariate analysis revealed that lesions at junctions (dentate line, sigmoid-descending junction, splenic flexure, hepatic flexure, ileocecal valve) and lesions with factors reflecting fibrosis in the submucosal layer (based on endoscopic findings before ESD) were significantly correlated with R0 resection failure, with adjusted odds ratios of 10.5 (95 % CI 2.1-67.6) and 10.4 (2.7-48.6), respectively.

CONCLUSIONS

Colorectal ESD is feasible for experienced endoscopists with limited experience in gastric ESD. Novices should avoid lesions at junctions or those with factors reflecting fibrosis.

Clip closure of defect after endoscopic resection in patients with larger colorectal tumors decreased the adverse events

BACKGROUND

Clip closure of large colorectal mucosal defects may reduce the rate of adverse events in a cost-effective manner.

OBJECTIVE

To assess the adverse events and outcomes of clip closure of defects after endoscopic resection in patients with large colorectal tumors.

DESIGN

Prospective, randomized, controlled study.

SETTING

Single tertiary referral center.

PATIENTS AND INTERVENTIONS

Patients with lesions measuring 1 to 4 cm who were scheduled for endoscopic resection between March 2012 and December 2014 were randomly assigned to a clip-closure group and a no-closure group. In the clip-closure group, the defect of the resection site was completely closed with an endoclip. In the no-closure group, the defect was left open. The following primary outcome measures were assessed: delayed postoperative bleeding, postpolypectomy coagulation syndrome, perforation, and abdominal pain. Secondary outcome measures of length of hospital stay, time required for procedure, and patient's satisfaction were also assessed.

RESULTS

Patients and lesions had similar characteristics across both groups. For patients who underwent clip closure (n = 174), the rates of delayed postoperative bleeding (1.1% [2/174]) and postpolypectomy coagulation syndrome (0.6% [1/174]) were lower than those in the no-closure group (6.9% [12/174], P = .01 and 4.6% [8/174], P = .03). Two patients experienced perforation, 1 in each group. In the clip-closure group, 4 patients reported abdominal pain as opposed to 26 in the no-closure group (2.8% vs 16.7%, P < .01). The procedure took longer in the closure group (38.1 minutes vs 30.9 minutes, P = .04). The length of hospitalization was shorter in the closure group (3.1 days vs 4.7 days, P = .03). Total medical expense was similar between the 2 groups. Patients who underwent closure reported greater satisfaction.

LIMITATION

This was a single-center analysis.

CONCLUSIONS

Clip closure of endoscopic resection defects in patients with large colorectal tumors decreased the rate of procedure-related adverse events and did not increase the cost of hospitalization.

Endoscopic submucosal dissection versus local excision for early rectal cancer: a systematic review and meta-analysis

Endoscopic submucosal dissection (ESD) and local excision (LE) are minimally invasive procedures that can be used to treat early rectal cancer. There are no current guidelines or consensus on the optimal treatment strategy for these lesions. A systematic review was conducted to compare the efficacy and safety of ESD and LE. A meta-analysis was conducted following all aspects of the Cochrane Handbook for systematic reviews and preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement. To perform the statistical analysis, the odds ratio (OR) was used for categorical variables and the weighted mean difference (WMD) for continuous variables. Four studies, involving a total of 307 patients, were identified. The length of hospital stay was longer in the group of patients undergoing LE [weighted mean difference (WMD) -1.94; 95% CI -2.85 to -1.02; p < 0.0001]. The combined results of the individual studies showed no significant differences as regards en-bloc resection rate (OR 0.82; 95% CI 0.25-2.70; p = 0.74), R0 resection rate (OR 1.53; 95% CI 0.62-3.73; p = 0.35), overall complication rate (OR 0.67; 95% CI 0.26-1.69; p = 0.40), and tumor size (WMD 0.57; 95% CI -3.64 to 4.78; p = 0.79) between ESD and LE. When adopting the fixed effect model which takes into account the study size, ESD was associated with a lower recurrence rate than LE (OR 0.15; 95% CI 0.03-0.87; p = 0.03), while with the random-effect model the difference was not significant (OR 0.18; 95% CI 0.02-2.04; p = 0.17). Over the last decade improvements in technology have improved the technical feasibility of rectal ESD. In specialized centers with highly experienced endoscopists, ESD can provide high-quality en-bloc excision of rectal neoplasms equivalent to traditional local excision.

New endoscopic platform for endoluminal en bloc tissue resection in the gastrointestinal tract (with videos)

BACKGROUND

Endoscopic removal of gastrointestinal tract lesions is increasingly popular around the world. We evaluated feasibility, safety, effectiveness, and user learning curve of new endoscopic platform for complex intraluminal interventions.

METHODS

A novel system, consisting of expandable working chamber with two independent instrument guides (LIG), was inserted into colon. Simulated colonic lesions were removed with endoscopic submucosal (ESD) and submuscular (ESmD) dissection.

RESULTS

In all nine in vivo models, an intraluminal chamber and its dynamic tissue retractors (via LIG) provided a stable working space with excellent visualization and adequate access to target tissue. Endoscopic platform facilitated successful completion of 11 en bloc ESDs (mean size 43.0 ± 11.3 mm, mean time 46.3 ± 41.2 min) and eight ESmD (mean size 50.0 ± 14.1 mm, mean time 48.0 ± 21.2 min). The learning curve for ESD using this platform demonstrated three phases: rapid improvement in procedural skills took place during the first three procedures (mean ESD time 98.7 ± 40.0 min). A plateau phase then occurred (procedures 4-7) with mean procedure time 42.0 ± 13.4 min (p = 0.04), followed by another sharp improvement in procedural skills (procedures 8-11) requiring only 16.3 ± 11.4 min (p = 0.03) to complete ESD. Especially dramatic (p = 0.002) was the time difference between the first three procedures (mean time 98.7 ± 40.0 min) and subsequent eight procedures (mean time 29.1 ± 17.9 min).

CONCLUSIONS

A newly developed endoscopic platform provides stable intraluminal working space, dynamic tissue retraction, and instrument triangulation, improving visualization and access to the target tissue for safer and more effective en bloc endoscopic submucosal and submuscular dissection. The learning curve for ESD was markedly facilitated by this new endoscopic platform.

Clinical pathway to discharge 3 days after colorectal endoscopic submucosal dissection

BACKGROUND AND AIM

Colorectal endoscopic submucosal dissection (ESD) is a useful treatment method; however, no index has been established for time for patient to start food ingestion or be discharged after ESD. We investigated the potential of a clinical pathway in which patients started food ingestion on day 2 after ESD and were discharged on day 3.

METHODS

A total of 382 patients underwent colorectal ESD between 2006 and 2012. A flow chart of a clinical pathway was prepared based on the data obtained, with the aim of shortening hospital stay after ESD.

RESULTS

Mean duration of postoperative hospital stay in the 382 patients was 5.3 ± 1.8 days. The most common cause of extended hospital stay was abnormal blood test finding, as detected in 50 patients in group C (n = 131; 38.2%), followed by careful course observations, as noted in 48 patients in group C (n = 131; 36.6%). Regarding procedural accidents as a result of ESD, intraoperative perforation occurred in 15 patients (3.9%) and post-ESD bleeding in seven patients (1.8%), which extended the hospital stay. Food ingestion was started on day 2 when no abnormality was noted during ESD or in physical and imaging findings or blood tests on day 1. In the 86 patients who underwent the prepared clinical pathway as a validation study, 68 (79.0%) were discharged on day 3. Duration of postoperative hospital stay was 3.4 ± 1.2 days.

CONCLUSION

Discharge may be possible 3 days after ESD when no abnormalities are noted during ESD or on post-ESD day 1.

Risk of lens cloudiness during colorectal endoscopic submucosal dissection and ability of a novel lens cleaner to maintain and restore endoscopic view

BACKGROUND AND AIM

Generally, colorectal endoscopic submucosal dissection (ESD) cannot be carried out with severe lens cloudiness. We examined the occurrence of lens cloudiness during ESD as well as the efficacy of a novel cleaner for it.

METHODS

This study was a prospective study compared to historical control. First, we analyzed 103 ESD cases using standard cleaner at the Kyoto Prefectural University of Medicine in 2012. Relationship between lens cloudiness and clinical characteristics of lesions was analyzed. Lens cloudiness was recorded as grade 0 (clear) to grade 2 (very unclear). Then, we recruited 92 consecutive patients who underwent colorectal ESD using the novel cleaner from August 2013 to July 2014. The cleaner was applied on top of the lens before procedure and ability to prevent lens cloudiness was tested. Additionally, the novel cleaner was injected from endoscopic channel into a space created by endoscopic hood and colonic wall in seven cases with grade 1 or 2 of lens cloudiness and the ability to clean lens cloudiness inside the colon was tested.

RESULTS

Rate of severe lens cloudiness was 8.7%. Multivariate analysis showed that severe lens cloudiness was related with severe submucosal fatty tissue (P < 0.001). The novel cleaner had significantly less cloudiness cases compared to the standard cleaner (14.1% vs 33.0%, P = 0.002). Additionally, the novel cleaner enabled us to clean lens cloudiness in all seven cases.

CONCLUSION

Lens cloudiness during ESD was associated with submucosal fatty tissue. Effective lens cleaner should be used to prevent and clean lens cloudiness.

Assessment and management of the malignant colorectal polyp

Colorectal cancer is the second most common cancer affecting men and women in England. The introduction of National Bowel Cancer Screening in 2006 has led to a rise in the proportion of colorectal cancers detected at an early stage. Many screen-detected cancers are malignant colorectal polyps and may potentially be cured with endoscopic resection, without recourse to the risk of major surgery or prolonged adjuvant therapies. Endoscopic decision making is crucial to select those early lesions that may be suitable for local endoscopic excision as well as identifying lesions for surgical resection, thus avoiding unnecessary surgical intervention in some and ensuring potentially curative surgery in others. This paper uses the current evidence base to provide a structured approach to the assessment of potentially malignant polyps and their management. http://group.bmj.com/products/journals/instructions-for-authors/licence-forms.

Efficacy and adverse events of EMR and endoscopic submucosal dissection for the treatment of colon neoplasms: a meta-analysis of studies comparing EMR and endoscopic submucosal dissection

BACKGROUND

EMR and endoscopic submucosal dissection (ESD) are used frequently to remove colon neoplasms. However, the predominance of these procedures has not yet been thoroughly explored.

OBJECTIVE

To compare the efficacy and adverse events related to EMR with those related to ESD for colon neoplasms.

DESIGN

A meta-analysis of 8 studies published between 2005 and 2013.

SETTING

Multicenter review.

PATIENTS

Patients from 8 studies yielding 2299 lesions.

INTERVENTIONS

EMR or ESD.

MAIN OUTCOME MEASUREMENTS

En bloc resection, curative resection, recurrence, and adverse events.

RESULTS

The pooled odds ratios (OR) (OR [95% confidence interval]) for the tumor size, length of the procedure, en bloc resection, curative resection, recurrence, additional surgery, delayed bleeding, and perforation by ESD versus EMR were 7.38 (6.42-8.34), 58.07 (36.27-79.88), 6.84 (3.30-14.18), 4.26 (3.77-6.57), 0.08 (0.04-0.17), 2.16 (1.16-4.03), 0.85 (0.45-1.60), and 4.96 (2.79-8.85), respectively.

LIMITATIONS

This analysis included only nonrandomized studies.

CONCLUSION

The size of the tumor and rate of en bloc resection and curative resection were higher, and the rate of recurrence was lower in the ESD group versus the EMR group. However, in the ESD group, the procedure was longer, and the rate of additional surgery and perforation was higher, suggesting that the indications for ESD should therefore be rigorously determined in order to avoid such problems.

Untutored learning curve to establish endoscopic submucosal dissection on competence level

BACKGROUNDS/AIMS

Endoscopic submucosal dissection (ESD) of early cancer allows precise staging and avoids recurrence or surgery. Tutored by experts, ESD has rapidly spread in Japan, but still demands untutored learning in Western countries. A step-up approach starts with easiest gastric neoplasias, but fails on their low prevalence in Western countries. A prevalence-based approach includes challenging colonic neoplasias.

METHODS

We analyzed an untutored series of initial 50 ESD procedures by an experienced endoscopist on consecutive lesions referred according to prevalence.

RESULTS

Overall, 48 lesions (20% upper gastrointestinal, 80% colorectal; 2 hyperplastic (inflammatory) lesions, 46 neoplasms) were completely resected intention-to-treat with ESD, 2 required a second ESD. Neoplasias were resected 76% en-bloc (46% ESD, 30% ESD with snaring), 17% by ESD with snaring in 2-3 pieces, and 6.5% as ESD with snaring in multiple pieces. None of 15 neoplasias with high-grade intraepithelial neoplasia or an early esophageal cancer (R0) had recurred. Complications were 2 bleedings (4%) and 7 perforations (14%), 5 clipped and 2 (4%) operated. All patients were discharged within 9 days without long-term morbidity.

CONCLUSION

Untutored learning of ESD is feasible on colonic lesions. We propose to establish ESD in Europe with structured training and a prevalence-of-lesions-based approach.