Endoscopic submucosal dissection: a safe technique for colorectal tumors

A case of disseminated peritoneal metastases after 2-year conservative treatment for intramucosal colon carcinoma due to a perforation during endoscopic submucosal dissection

A 70-year-old man was admitted to our hospital for the treatment of a large granular-type laterally spreading tumor in the splenic flexure of the descending colon. The preoperative diagnosis was intramucosal colon carcinoma and endoscopic submucosal dissection was performed. During treatment, a small perforation occurred accidentally. After conservative treatment with endoscopic suturing, the patient was discharged without additional surgery. The pathological diagnosis was an intramucosal carcinoma. One year after treatment, no local recurrence was observed on endoscopy, and abdominal computed tomography showed no obvious metastasis. Two years later, fluorodeoxyglucose-positron emission tomography/computed tomography, laparoscopic findings, and histopathologic findings by experimental excision of omentum revealed several disseminated peritoneal metastases from previously treated colon carcinoma. To the best of our knowledge, this is the first report of peritoneal dissemination after a small perforation during endoscopic submucosal dissection and conservative therapy for early-stage colon carcinoma. This report suggests the possibility of tumor dissemination in patients with small perforations during endoscopic procedures. Endoscopists should be aware of these rare potential risks and perform later surveillance carefully.

A novel nomogram for the prediction of perforation during endoscopic submucosal dissection for colorectal neoplasms

BACKGROUND

High perforation risk hinders the widespread adoption of ESD for colorectal neoplasms. This study was performed to determine the risk factors of colorectal endoscopic submucosal dissection (ESD)-induced perforation and develop a predictive model.

METHODS

A total of 1046 colorectal neoplasms in 1011 patients were retrospectively enrolled from January 2011 to December 2021, in a single tertiary center as the derivation cohort. We identified independent risk factors for perforation using univariate analysis and multi-variate logistic regression. A nomogram was developed based on the logistic regression model and prospectively applied to 266 colorectal neoplasms as the validation cohort. The performance of the predictive model was evaluated with the receiver operating characteristic curve, calibration plot, and decision curve analysis.

RESULTS

Independent pre-operative factors for colorectal ESD-induced perforation were tumor located in the left colon [odds ratio (OR) 2.39, P = 0.040], size ≥ 40 mm (OR 3.36, P < 0.001), ≥2/3 circumference (OR 7.55, P = 0.004), located across folds (OR 6.26, P < 0.001), and laterally spreading tumor (non-granular type, OR 2.34, P = 0.029; granular type, OR 2.46, P = 0.021). The nomogram model incorporating the pre-operative factors performed well in both the derivation and validation cohorts (areas under the curve of 0.750 and 0.806, respectively). Decision curve analysis demonstrated that the clinical benefit of the nomogram was favorable.

CONCLUSIONS

The novel nomogram, developed and prospectively validated, incorporating tumor size, location, and morphology can successfully predict perforation during ESD for colorectal neoplasms.

Improved hydration property of tissue adhesive/hemostatic microparticle based on hydrophobically-modified Alaska pollock gelatin

The management of bleeding is an important aspect of endoscopic surgery to avoid excessive blood loss and minimize pain. In clinical settings, sprayable hemostatic particles are used for their easy delivery, adaptability to irregular shapes, and rapid hydration. However, conventional hemostatic particles present challenges associated with tissue adhesion. In a previous study, we reported tissue adhesive microparticles (C10-sa-MPs) derived from Alaska pollock gelatin modified with decyl groups (C10-sa-ApGltn) using secondary amines as linkages. The C10-sa-MPs adhere to soft tissues through a hydration mechanism. However, their application as a hemostatic agent was limited by their long hydration times, attributed to their high hydrophobicity. In this study, we present a new type microparticle, C10-am-MPs, synthesized by incorporating decanoyl group modifications into ApGltn (C10-am-ApGltn), using amide bonds as linkages. C10-am-MPs exhibited enhanced hydration characteristics compared to C10-sa-MPs, attributed to superior water absorption facilitated by amide bonds rather than secondary amines. Furthermore, C10-am-MPs demonstrated comparable tissue adhesion properties and underwater adhesion stability to C10-sa-MPs. Notably, C10-am-MPs exhibited accelerated blood coagulation in vitro compared to C10-sa-MPs. The application of C10-am-MPs in an in vivo rat liver hemorrhage model resulted in a hemostatic effect comparable to a commercially available hemostatic particle. These findings highlight the potential utility of C10-am-MPs as an effective hemostatic agent for endoscopic procedures and surgical interventions.

Risk Prediction of Post-Endoscopic Submucosal Dissection Coagulation Syndrome

INTRODUCTION

Endoscopic submucosal dissection (ESD) has been popular worldwide to treat laterally spreading tumors and large polyps. Post-ESD coagulation syndrome (PECS) is more common than the two major ESD-related complications, perforation, and bleeding. The aim of this study was to assess the prevalence of PECS, identify the risk factors for PECS, and create a risk prediction model for PECS.

METHODS

Retrospective cross-sectional study analyzed a total of 986 patients who underwent colorectal ESD. Logistic regression models were used to assess risk factors with PECS. Each risk factor was scored, and the 3-step risk stratification index of prediction model was assessed.

RESULTS

The prevalence of PECS was 21.4% (95% confidence interval [CI] = 18.9-24.1%). The risk factors of PECS in the multivariate logistic regression were tumor size (+1 cm: odds ratio [OR], 1.29; 95% CI, 1.16-7.09), cecal lesion (OR, 1.96; 95% CI, 1.09-1.53), procedure time (+30 min: OR, 1.19; 95% CI, 1.02-1.39), and ESD with snaring (OR, 0.64; 95% CI, 0.43-0.95). Applying a simplified weighted scoring system based on adjusted OR increments of 1, the risk of PECS was 12.3% (95% CI, 0.3-16.0%) for the low-risk group (score ≤4) and was 36.0% (95% CI = 29.4-43.2%) for the high-risk group (score ≥8). Overall discrimination (C-statistic = 0.629; 95% CI = 0.585-0.672) and calibration (p = 0.993) of the model were moderate to good.

CONCLUSION

PECS occurs frequently, and the prediction model can be helpful for effective treatment and prevention of PECS.

Endoscopic submucosal dissection for colorectal neoplasms: Risk factors for local recurrence and long-term surveillance

Objectives

Endoscopic submucosal dissection (ESD) is an effective procedure for the en bloc resection of colorectal neoplasms. However, risk factors for local recurrence after ESD have not been identified. This study aimed to evaluate such risk factors after ESD for colorectal neoplasms.

Methods

This retrospective study included 1344 patients with 1539 consecutive colorectal lesions who underwent ESD between September 2003 and December 2019. We investigated various factors associated with local recurrence in these patients. The main outcomes were the incidence of local recurrence and its relationship with clinicopathological factors during long-term surveillance.

Results

The en bloc resection rate was 98.6%, the R0 resection rate was 97.2%, and the histologically complete resection rate was 92.7%. Local recurrence was observed in 7/1344 (0.5%) patients and the median follow-up period was 72 months (range 4-195 months). The incidence of local recurrence was significantly higher in lesions ≥40 mm in diameter (hazard ratio [HR] 15.68 [1.88-130.5]; p = 0.011), piecemeal resection (HR 48.42 [10.7-218.7]; p < 0.001), non-R0 resection (HR 41.05 [9.025-186.7]; p < 0.001), histologically incomplete resection (HR 16.23 [3.627-72.63]; p<0.001), and severe fibrosis (F2; HR 9.523 [1.14-79.3]; p = 0.037).

Conclusions

Five risk factors for local recurrence after ESD were identified. Patients with such factors should undergo careful surveillance colonoscopy.

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

Objectives

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

Methods

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

Results

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

Conclusions

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

Impact of prophylactic wound closure in colorectal ESD on postoperative wound complications: A meta-analysis

Endoscopic submucosa dissection (ESD) has been applied extensively in the treatment of large intestine tumours due to its high total excision ratio. Nevertheless, there is a high incidence of adverse reactions in colon ESD, and the efficacy of prophylactic ESD following ESD in prevention of postoperative haemorrhage is still disputed. The purpose of this meta-analysis is to evaluate the effectiveness of prophylaxis of wound closure in large intestine ESD after operation. For eligibility, we looked through three databases: PubMed, Embase and Cochrane Library. Heterogenity was measured by means of a chi-square method of Q-statistic and an I2 test. Fixed or random effects models were used for data processing. Based on the retrieval policy, we found a total of 1286 papers, and then we collected nine papers to extract the data. Regarding postoperative haemorrhage, there was a significant reduction in the risk of wound haemorrhage in the wound closure group than in the control group (OR, 0.29; 95% CI, 0.19-0.44 p < 0.0001). No statistical significance was found in the incidence of perforation in the wound closure and the control group (OR, 0.45; 95% CI, 0.19-1.03 p = 0.06). There was a significant reduction in the incidence of postoperation fever among those in the wound closure group than in the control group (OR, 0.37; 95% CI, 0.15-0.93 p = 0.04). Preventive endoscopic closure decreased the rate of ESD in colon disease, but did not significantly decrease the rate of postoperation perforation and postoperative fever. Future research will be required to clarify the risk factors and classify high-risk individuals in order to formulate a cost-effective prevention strategy.

Hybrid endoscopic submucosal dissection as a salvage option for difficult colorectal conventional endoscopic submucosal dissection

BACKGROUND

When total submucosal dissection is difficult to achieve during conventional colorectal endoscopic submucosal dissection (C-ESD), the lesion can be resected by final snaring through salvage hybrid ESD (SH-ESD). This study aimed to examine the outcomes of SH-ESD and identify its indications that could achieve en bloc resection.

METHODS

We recruited 1039 consecutive patients with colorectal lesions that underwent ESD at Hiroshima University Hospital between January 2015 and December 2020. C-ESD was attempted thoroughly in 924 lesions (C-ESD group, including 9 lesions in which ESD was discontinued), and SH-ESD was performed owing to some difficulties in 115 lesions (SH-ESD group). Risk factors for incomplete resection by SH-ESD and ESD discontinuation were evaluated using multivariate analysis. The outcomes were compared between cases with remaining undissected submucosa of < 20 mm in diameter in the SH-ESD and C-ESD groups, using propensity score matching.

RESULTS

Multivariate analysis revealed that a procedure time > 80 min and remaining undissected submucosa ≥ 20 mm in diameter were significant risk factors for incomplete resection after SH-ESD and ESD discontinuation. By propensity score matching analysis, procedure time was significantly shorter in the SH-ESD group with remaining undissected submucosa < 20 mm in diameter than in the C-ESD group (71 min vs. 90 min, p = 0.0053), although no significant difference was found in the en bloc resection rate (94% vs. 87%, p = 0.0914).

CONCLUSION

SH-ESD can be an alternative surgical method when conventional ESD is difficult to continue in cases in which the remaining undissected submucosa is < 20 mm in diameter.

Colorectal Endoscopic Submucosal Dissection: Performance of a Novel Hybrid-Technology Knife in an Animal Trial

Endoscopic submucosal dissection (ESD) was developed for the removal of benign and early malignant lesions in the gastrointestinal tract. We aimed to evaluate the performance and safety of a novel high-pressure waterjet-assisted ESD knife in colorectal applications. Six female German Landrace pigs with an average weight of 62 kg (range 60-65 kg) were used in this prospective, randomized, and controlled study. Twenty-four ESDs were performed by three endoscopists: Twelve each with the new Erbe HYBRIDknife® flex T-Type (HK-T) and the Olympus DualKnife® J (DK-J), including six rectal and six colonic ESDs per instrument. The order of performance was randomized regarding anatomic position and instrument. As the primary endpoint, ESD knife performance characteristics were combined and rated on a 5-point Likert scale, with 5 Likert points (LP) representing the best response (5 = very good). The HK-T was rated significantly better than the DK-J (4.7 LP versus 4.4 LP, p = 0.0295), mainly because of HK-T injection ability (5 LP versus 3 LP, p < 0.0001) and hemostasis (5 LP versus 4 LP, p = 0.0452). There was no difference in procedure time (HK-T: 35 min versus DK-J: 34 min, p = 0.8005), resection diameter (3.1 cm versus 2.8 cm, p = 0.3492), injection volume (41 mL versus 46 mL, p = 0.5633), and complication rates. HK-T is as effective as DK-J in colorectal ESD in terms of dissection quality but has better injection and hemostatic properties. The impact of these technical advantages on the ESD treatment of patients with large superficial colorectal lesions remains to be clinically verified.

En bloc resection of bladder tumour: the rebirth of past through reminiscence

PURPOSE

To learn about the history and development of en bloc resection of bladder tumour (ERBT), and to discuss its future directions in managing bladder cancer.

METHODS

In this narrative review, we summarised the history and early development of ERBT, previous attempts in overcoming the tumour size limitation, consolidative effort in standardising the ERBT procedure, emerging evidence in ERBT, evolving concepts in treating large bladder tumours, and the future directions of ERBT.

RESULTS

Since the first report on ERBT in 1980, there has been tremendous advancement in terms of its technique, energy modalities and tumour retrieval methods. In 2020, the international consensus statement on ERBT has been developed and it serves as a standard reference for urologists to practise ERBT. Recently, high-quality evidence on ERBT has been emerging. Of note, the EB-StaR study showed that ERBT led to a reduction in 1-year recurrence rate from 38.1 to 28.5%. An individual patient data meta-analysis is currently underway, and it will be instrumental in defining the true value of ERBT in treating non-muscle-invasive bladder cancer. For large bladder tumours, modified approaches of ERBT should be accepted, as the quality of resection is more important than a mere removal of tumour in one piece. The global ERBT registry has been launched to study the value of ERBT in a real-world setting.

CONCLUSION

ERBT is a promising surgical technique in treating bladder cancer and it has gained increasing interest globally. It is about time for us to embrace this technique in our clinical practice.

Outcomes for Underwater Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection of 21-30-mm Colorectal Polyps: A Feasible Study

BACKGROUND AND AIMS

This randomized controlled trial (RCT) was designed to evaluate the short-term outcomes of underwater endoscopic mucosal resection (UEMR) and endoscopic submucosal dissection (ESD) of 21-30 mm colonic polyps.

METHOD

We conducted a single-center RCT. Patients diagnosed with suspected colorectal intramucosal carcinoma (21-30 mm and adaptable for both UEMR and ESD) were randomly assigned to the UEMR and ESD groups at a 1:1 ratio. The primary endpoint was the R0 resection rate. We independently performed one-sample tests against the set threshold for each treatment. The significance level was set at p = 0.224.

RESULT

Eleven polyps each in the UEMR and ESD groups, respectively, were analyzed. The R0 resection rate (%) was 36 (95% confidence interval 11-69) and 100 (72-100) for UEMR and ESD, respectively, with a significant difference between the two groups (p = 0.002). The p-value against the set threshold for UEMR was 0.743, whereas that for ESD was < 0.001 (one-sample binomial test). The en bloc resection rates (%) were 82 (48-97) and 100 (72-100) for UEMR and ESD, respectively; however, no significant difference was observed (p = 0.167). The mean treatment time (min) was significantly shorter in the UEMR group (8 ± 6) than in the ESD group (48 ± 29) (p = 0.001).

CONCLUSION

ESD could achieve a high R0 resection rate, while the en bloc resection rate was comparable between the two treatment techniques with less burden on patients undergoing UEMR for 21-30-mm colorectal polyps.

CLINICAL TRIAL REGISTRATION

The study was registered at the Japan Registry of Clinical Trial as jRCT1030210015 and jRCT1030210177.

Safety and efficacy of a novel suturing device for closure of large defects after endoscopic submucosal dissection (with video)

BACKGROUND AND AIMS

Endoscopic suturing enables full closure of large defects after endoscopic submucosal dissection (ESD). However, its use is limited by the need for a double-channel endoscope. A novel closure system, the OverStitch Sx (Apollo Endosurgery, Austin, Tex, USA), compatible with any single-channel endoscope, was introduced to address these shortcomings. The aim of this study was to assess the safety and feasibility of OverStitch Sx for the closure of large defects after ESD.

METHODS

This is a prospective single-center feasibility study of patients who underwent closure of large defects after ESD using the OverStitch Sx system. Main outcomes of the study are technical and clinical success, same-day discharge rate, and adverse event rate.

RESULTS

Thirty-three patients were enrolled. The mean diameter of included lesions was 5.38 ± 2.52 cm. The defect occupied ≥50% of the lumen circumference in 70% of the cases. En-bloc resection, R0 resection, and curative resection were achieved in 97%, 87.5%, and 78.8% of patients, respectively. Technical success and clinical success were seen in 93.9% and 90.9% of the cases, respectively. Same-day hospital discharge was achieved in 77.4% of patients. Total adverse event rate was 35.7%, including delayed bleeding in 1 patient after rectal ESD that was managed conservatively, self-resolving rectal pain in 7 patients, rectal stricture requiring dilation in 1 patient, and temporary dysphagia in 1 patient. No immediate or delayed perforation was reported.

CONCLUSIONS

OverStitch Sx enabled safe and effective closure of large defects after ESD. Future trials are needed to determine its superiority over OverStitch for the closure of defects in challenging locations. (Clinical trial registration number: NCT04361227.).

Effect of particle size on the tissue adhesion and particle floatation of a colloidal wound dressing for endoscopic treatments

Endoscopic submucosal dissection (ESD) is a minimally invasive technique that is widely used to remove gastrointestinal tumors. However, because the walls of the duodenum and large intestine are thin, perforation can easily occur after ESD. We have previously reported that alkyl group-modified Alaska pollock gelatin-based microparticles (C10Ps) formed a colloidal gel that could adhere to defects and close perforations, driven by hydrophobic interactions. The present study focused on the effect of particle size on the colloidal gel properties and the floatation of C10Ps in the air in the delivery of C10Ps. We prepared C10Ps with different particle sizes from 0.1 to 100 µm. The storage modulus and adhesion strength of the C10P colloidal gel increased with decreasing particle size. All the C10Ps formed a colloidal gel layer on duodenum tissue after being sprayed from an endoscopic device. The underwater stability and burst strength of C10Ps with a particle size of 0.1 and 1 µm were higher than for larger C10Ps. Floating of the small-sized C10Ps in the air was observed. The results indicated that C10Ps with a size of 1 µm had suitable properties for use in endoscopic treatments. STATEMENT OF SIGNIFICANCE: We previously reported tissue adhesive microparticles as a spray-deliverable wound dressing in gastrointestinal tissues. However, their functions depending on particle size have not yet been clarified. In the present study, we prepared decyl group-modified Alaska pollock gelatin nano and microparticles (C10Ps) with different particle sizes from 0.1 to 100 µm and evaluated the effect of particle size on the colloidal gel properties (rheological property, underwater stability and perforation-closing ability) and the floatation of C10Ps in the air in the delivery of C10Ps.

Studies on endoscopic submucosal dissection in the past 15 years: A bibliometric analysis

Background and aims

Endoscopic submucosal dissection (ESD) is an advanced minimally invasive technique for en bloc resection of superficial gastrointestinal lesions, which is drawn an increasing attention from its emergence. This bibliometric analysis is to evaluate the origin, current hotspots, and research trends on ESD.

Methods

A total of 2,131 publications on ESD from 2006 to 2020 were obtained from the Web of Science Core Collection (WoSCC) database. Bibliometric visualization analyses of countries/regions, institutes, authors, journals, references and keywords were performed by CiteSpace V.5.8.R3.

Results

The quantity of publications on ESD increased significantly during the past 15 years. Japan occupied the leading position in terms of research power. Professor Yutaka Saito, together with the institute he belongs, the Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan, were the most productive author and institute, respectively. Colorectal ESD led the main thematic concentrations in ESD research. The most prolific journal was Gastrointestinal Endoscopy. European ESD Guideline was the most frequently co-cited reference. Guideline, meta-analysis, endoscopic resection, poly-glycolic acid sheet, Barrett's esophagus, fibrin glue, risk and colorectal neoplasm will be the active research hotspots in the future.

Conclusions

These findings provide the trends and frontiers in the field of ESD, as well as valuable information for clinicians and scientists to discover the future perspectives with potential collaborators.

Potential Factors Predicting Histopathologically Upgrade Discrepancies between Endoscopic Forceps Biopsy of the Colorectal Low-Grade Intraepithelial Neoplasia and Endoscopic Resection Specimens

Background

It was gradually accepted that endoscopic fragment biopsy (EFB) diagnosis cannot accurately guarantee the absence of higher-grade neoplasms within the lesion of the digestive tract. There are no well-established predictors for histopathologically upgrade discrepancies between EFB diagnosing colorectal low-grade intraepithelial neoplasia (LGIN) and endoscopic resection (ER) specimens.

Methods

A total of 918 colorectal LGINs was histopathologically diagnosed by EFB, including 162 cases with upgrade discrepancy and 756 concordant cases. We compared clinicopathological data of EFB and ER specimens between these two groups. Multivariate analysis was performed to identify predictors for this upgrade histopathology.

Results

The predominant upgrade discrepancy of LGINs diagnosed by EFB was upgrades to high-grade dysplasia (114/918, 12.4%), followed by upgrades to intramucosal carcinoma (33/918, 3.6%), submucosal adenocarcinoma (10/918, 1.1%), and advanced adenocarcinoma (5/918, 0.5%). NSAID history (OR 4.83; 95% CI, 2.27-10.27; p < 0.001), insufficient EFB number (OR 2.99; 95% CI, 1.91-4.68; p < 0.001), maximum diameter ≥ 1.0 cm (OR 6.18; 95% CI, 1.32-28.99; p = 0.021), lobulated shape (OR 2.68; 95% CI, 1.65-4.36; p < 0.001), erythema (OR 2.42; 95% CI, 1.50-3.91; p < 0.001), erosion (OR 7.12; 95% CI, 3.91-12.94; p < 0.001), surface unevenness (OR 2.31; 95% CI, 1.33-4.01; p = 0.003), and distal location of the target adenoma (OR 3.29; 95% CI, 1.68-6.41; p < 0.001) were associated with the histologically upgrade discrepancies.

Conclusion

NSAID history, insufficient EFB number, adenoma size and location, and abnormal macroscopic patterns are potential predictors for upgrade histopathology of LGINs diagnosed by EFBs. The standardization of EFB number and advanced imaging techniques could minimize the risk of neglecting the potential of this upgrade histopathology.

Is underwater endoscopic mucosal resection of colon polyps superior to conventional techniques? A network analysis of endoscopic mucosal resection and submucosal dissection

Background and study aims  Evidence from recent trials comparing conventional endoscopic mucosal resection (EMR) to underwater EMR (UEMR) have matured. However, studies comparing UEMR to endoscopic submucosal dissection (ESD) are lacking. Hence, we sought to conduct a comprehensive network meta-analysis to compare the efficacy of UEMR, ESD, and EMR. Methods  Embase and Medline databases were searched from inception to December 2020 for articles comparing UEMR with EMR and ESD. Outcomes of interest included rates of en bloc and complete polyp resection, risk of perforation and bleeding, and local recurrence. A network meta-analysis comparing all three approaches was conducted. In addition, a conventional comparative meta-analysis comparing UEMR to EMR was performed. Analysis was stratified according to polyp sizes (< 10 mm, ≥ 10 mm, and ≥ 20 mm). Results  Twenty-two articles were included in this study. For polyps ≥ 10 mm, UEMR was inferior to ESD in achieving en bloc resection ( P  = 0.02). However, UEMR had shorter operating time for polyps ≥ 10 mm ( P  < 0.001), and ≥20 mm ( P  = 0.019) with reduced perforation risk for polyps ≥ 10 mm ( P  = 0.05) compared to ESD. In addition, en bloc resection rates were similar between UEMR and EMR, although UEMR had reduced recurrence for polyps ≥ 10 mm ( P  = 0.013) and ≥ 20 mm ( P  = 0.014). UEMR also had shorter mean operating than EMR for polyps ≥ 10 mm ( P  < 0.001) and ≥ 20 mm ( P  < 0.001). Risk of bleeding and perforation with UEMR and EMR were similar for polyp of all sizes. Conclusions  UEMR has demonstrated technical and oncological outcomes comparable to ESD and EMR, along with a desirable safety profile. UEMR appears to be a safe and effective alternative to conventional methods for resection of polyps ≥ 10 mm.

Efficacy and safety of a thermosensitive hydrogel for endoscopic submucosal dissection: An in vivo swine study

Injectable thermo-sensitive chitosan hydrogels have recently been developed for the use of submucosal fluids in endoscopic submucosal dissections (ESD). This study aimed to investigate the efficacy and safety of chitosan hydrogels during ESD. Submucosal fluids were administered as follows: 0.9% normal saline (NS), 0.4% hyaluronic acid (HA) and chitosan/β-glycerophosphate (CS/GP) hydrogel. Each solution was administered twice into the stomach and colon of a pig, with a total of 72 ESD procedures performed on 12 pigs. The injected volume and procedure-related parameters were recorded and analyzed. ESDs that created ulcers after 7 days were histologically compared. All ESD specimens were resected en bloc. The total injected volumes during ESD of the stomach (NS, 16.09±3.27 vs. HA, 11.17±2.32 vs. CS/GP, 9.44±2.33; p<0.001) and colon (NS, 9.17±1.80 vs. HA, 6.67±1.50 vs. CS/GP, 6.75±1.57; p = 0.001) were significantly different. Hydrogel showed significant differences from normal saline in terms of fluid power (mm²/vol; NS, 35.70±9.00 vs. CS/GP 57.48±20.77; p = 0.001) and consumption rate (vol/min; NS, 2.59±0.86 vs. CS/GP, 1.62±0.65; p = 0.013) in the stomach. Histological examination revealed preserved muscularis propria, although the chitosan hydrogel resulted in a partial inflammatory response, with a hypertrophied submucosal layer. Chitosan hydrogel was found to be superior to normal saline, with an efficacy similar to that of hyaluronic acid. Nonetheless, long-term histological changes should be evaluated before clinical implementation.

Underwater vs Conventional Endoscopic Mucosal Resection of Large Sessile or Flat Colorectal Polyps: A Prospective Randomized Controlled Trial

BACKGROUND & AIMS

Conventional endoscopic mucosal resection (CEMR) with submucosal injection is the current standard for the resection of large, nonmalignant colorectal polyps. We investigated whether underwater endoscopic mucosal resection (UEMR) is superior to CEMR for large (20-40mm) sessile or flat colorectal polyps.

METHODS

In this prospective randomized controlled study, patients with sessile or flat colorectal polyps between 20 and 40 mm in size were randomly assigned to UEMR or CEMR. The primary outcome was the recurrence rate after 6 months. Secondary outcomes included en bloc and R0 resection rates, number of resected pieces, procedure time, and adverse events.

RESULTS

En bloc resection rates were 33.3% in the UEMR group and 18.4% in the CEMR group (P = .045); R0 resection rates were 32.1% and 15.8% for UEMR vs CEMR, respectively (P = .025). UEMR was performed with significantly fewer pieces compared to CEMR (2 pieces: 45.5% UEMR vs 17.7% CEMR; P = .001). The overall recurrence rate did not differ between both groups (P = .253); however, subgroup analysis showed a significant difference in favor of UEMR for lesions of >30 mm to ≤40 mm in size (P = .031). The resection time was significantly shorter in the UEMR group (8 vs 14 minutes; P < .001). Adverse events did not differ between both groups (P = .611).

CONCLUSIONS

UEMR is superior to CEMR regarding en bloc resection, R0 resection, and procedure time for large colorectal lesions and shows significantly lower recurrence rates for lesions >30 mm to ≤40 mm in size. UEMR should be considered for the endoscopic resection of large colorectal polyps.

Long-term prognosis after endoscopic submucosal dissection for colorectal tumors in patients aged over 80 years

Background

In Japan, endoscopic submucosal dissection (ESD) is standardized for large colorectal tumors. However, its validity in the elderly population is unclear. We aimed to evaluate the safety and efficacy of ESD for colorectal tumors in elderly patients aged over 80 years.

Methods

ESD was performed on 178 tumors in 165 consecutive patients aged over 80 years between December 2008 and December 2018. We retrospectively evaluated the clinicopathological characteristics and clinical outcomes of ESD. We also assessed the prognosis of 160 patients followed up for more than 12 months.

Results

The mean patient age was 83.7 ± 3.1 years. The number of patients with comorbidities was 100 (62.5%). Among all patients, 106 (64.2%) were categorized as class 1 or 2 according to the American Society of Anesthesiologists classification of physical status (ASA-PS), and 59 (35.8%) were classified as class 3. The mean procedure time was 97.7 ± 79.3 min. The rate of histological en bloc resection was 93.8% (167/178). Delayed bleeding in 11 cases (6.2%) and perforation in 7 cases (3.9%) were treated conservatively. The 5-year survival rate was 89.9%. No deaths from primary disease (mean follow-up time: 35.3 ± 27.5 months) were observed. Overall survival rates were significantly lower in the non-curative resection group that did not undergo additional surgery than in the curative resection group (P = 0.0152) and non-curative group that underwent additional surgery (P = 0.0259). Overall survival rates were higher for ASA-PS class 1 or 2 patients than class 3 patients (P = 0.0105). Metachronous tumors (> 5 mm) developed in 9.4% of patients.

Conclusions

ESD for colorectal tumors in patients aged over 80 years is safe. Colorectal cancer-associated deaths were prevented although comorbidities pose a high risk of poor prognosis.

Endoscopic submucosal dissection vs endoscopic mucosal resection for colorectal polyps: A meta-analysis and meta-regression with single arm analysis

BACKGROUND

Endoscopic submucosal dissection (ESD) has shown to be effective in management of colorectal neoplasm in the Asian countries, while its implementation in Western countries where endoscopic mucosal resection (EMR) is preferred is still debatable.

AIM

To compare the surgical, histological, and oncological outcomes between ESD and EMR in the treatment of colorectal polyps, with subgroup analysis comparing the efficacy of ESD and EMR between Japan and the rest of the world.

METHODS

Embase and Medline databases were searched from inception to October 2020 in accordance with PRISMA guidelines for studies comparing en bloc, complete resection, margin involvement, resection time, need for additional surgery, complications, and recurrence rate of ESD with EMR.

RESULTS

Of 281344 colorectal polyps from 21 studies were included. When compared to EMR, the pooled analysis revealed ESD was associated with higher en bloc and complete resection rate, and lower lateral margin involvement and recurrence. ESD led to increased procedural time, need for additional surgery, and perforation risk. No significant difference in bleeding risk was found between the two groups. Meta-regression analysis suggested only right colonic polyps correlated with an increased perforation risk in ESD. Confounders including polyp size and invasion depth did not significantly influence the en bloc and complete resection rate, bleeding risk and recurrence. In subgroup analysis, Japan performed better than the rest of the world in both ESD and EMR with perforation risk of 4% and 0.0002%, respectively, as compared to perforation risk of 8% and 1%, respectively, in reports coming from rest of the world.

CONCLUSION

ESD resulted in better resection outcomes and lower recurrence compared to EMR. With appropriate training, ESD is preferred over EMR as the first-line therapy for resection of colorectal polyps, without restricting to lesions greater than 20 mm and those with high suspicion of submucosal invasion.

Indications and outcomes of colorectal hybrid endoscopic submucosal dissection: a large multicenter 10-year study

BACKGROUND AND AIMS

Hybrid endoscopic submucosal dissection (ESD) is a colorectal lesion resection procedure that includes both planned and salvage procedures. Previous colorectal hybrid ESD studies have involved single institutions or few operators over a short timeframe, and the size for indication has not been established. In this multicentre study, we investigated the clinical outcomes of hybrid ESD for colorectal tumors that met the 30 mm lesion size criterion.

METHODS

From January 2008 to December 2018, colorectal hybrid ESD was performed for 172 lesions (diameter range, ≥ 20- < 30 mm) at Hiroshima GI Endoscopy Research Group. We compared clinicopathological characteristics and outcomes between 56 and 116 lesions in planned and salvage groups, respectively. We also compared data between 2008 and 2013 (the first period) and 2014 and 2018 (the second period) to assess operator experience.

RESULTS

No significant difference was found in the complete en bloc resection rate between the planned and salvage groups (92.9% vs. 83.6%, respectively). Procedure time was shorter in the planned group (44.5 min) than in the salvage group (72.0 min, p < 0.01). The perforation rate was higher in the salvage group (21.6%) than in the planned group (0%, p < 0.01); however, the perforation rate during snaring in the salvage group was 1.8%. During the second period relative to the first period, we recorded a significantly higher complete en bloc resection rate (95.7% vs. 75.6%, respectively, p < 0.01) and experienced operator rate (75.5% vs. 53.9%, respectively, p < 0.01). Furthermore, no significant difference was found in the complete en bloc resection rate between the planned and salvage groups during the second period (100% vs. 94.4%, respectively).

CONCLUSION

Colorectal hybrid ESD, especially salvage hybrid ESD performed by experienced operators, is adoptable and safe for lesions with diameters ranging from ≥ 20 to < 30 mm.

Robust closure of post-endoscopic submucosal dissection perforation by microparticle-based wound dressing

Endoscopic submucosal dissection (ESD) has been used as a minimally invasive cancer treatment for early-stage gastrointestinal cancer. However, cancer dissection in thin tissues, such as the duodenum and large intestine, often cause post-ESD and delayed perforation, which elicit severe complications. In this study, we report a microparticle-based wound dressing with hydrophobically-modified gelatin that can close the perforation after ESD. Hydrophobized microparticles were prepared using a coacervation method in a water/ethanol mixed solvent. The optimized alkyl chain length and degree of substitution of hydrophobic groups improved the mechanical strength of the hydrogel formed by hydration and fusion of the microparticles. The hydrogels formed on tissue defects revealed higher burst strength in ex vitro perforation models using duodenum, large intestine, and stomach under wet conditions compared with hydrogels without hydrophobic modification. The particle fusion was determined to be a crucial step to yield a high burst strength. An in vivo degradability evaluation showed that microparticle hydrogels subcutaneously implanted in rats degraded within 14 days. The microparticle wound dressing is expected to be applicable to post-ESD perforation and prevent delayed perforation.

Endoscopic submucosal dissection versus endoscopic mucosal resection for colorectal tumors: a systematic review and meta-analysis

OBJECTIVE

To compare early (resection quality, complication rate, surgery time) and long-term (recurrence rate) outcomes of endoscopic submucosal dissection versus endoscopic mucosal resection.

MATERIAL AND METHODS

A systematic review and meta-analysis was performed in accordance with the PRISMA guidelines. Data were analyzed using the Rewiew Manager 5.3 software.

RESULTS

The study included 8 manuscripts including 6 retrospective trials, 1 case-control and only 1 prospective study. These studies comprised the results of endoscopic resection of 1989 colonic tumors (EMR - 748, ESD - 1241). ESD is associated with higher incidence of en-bloc resection (OR 0.13; 95% CI 0.03 0.49; p=0.003) and R0 resection (OR 0.23; 95% CI 0.05 1.02; p=0.05) compared to EMR. Local recurrence rate is 13 times higher after EMR compared to ESD (OR 13.94; 95% CI 6.3 30.8; p=0.00001). However, ESD is followed by 4 times higher risk of colon wall perforation (OR 0.25; 95% CI 0.08 0.81; p=0.02).

CONCLUSION

ESD is more advisable regarding resection quality compared to EMR. However, higher incidence of perforations, surgery time and technical features of ESD do not allow us to unambiguously interpret the results of our meta-analysis and determine the optimal surgical approach.

Endoscopic mucosal resection versus endoscopic submucosal dissection for colorectal laterally spreading tumors: a meta-analysis

OBJECTIVE

to assess the efficacy and safety of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) in the treatment of colorectal laterally spreading tumors (LSTs).

METHODS

a systematic literature search was performed in PubMed, Embase, the Cochrane Library, CNKI and WANFANG databases. The related references were selected according to certain inclusion and exclusion criteria. The Cochrane Collaboration's Revman 5.3 software was used for data analysis.

RESULTS

a total of 12 studies were included in the analysis. The total number of lesions was 3,062 (EMR: 1,906; ESD: 1,156). The en-bloc resection rate of ESD was 95 % (1,098/1,156), which was significantly higher than that of EMR (42.8 %, 815/1,906) (OR = 0.07, 95 % CI [0.02, 0.07], p < 0.00001). The complete resection rate of ESD was 93.2 % (109/117), which was significantly higher than that of EMR as well (71.9 %, 92/128) (OR = 0.12, 95 % CI [0.05, 0.29], p < 0.00001). The bleeding rate showed no significant difference between EMR and ESD (4.2 % vs 3.5 %) (OR = 1.04, 95 % CI [0.68, 1.60], p = 0.85). The perforation rates of EMR and ESD were 1.8 % and 2.4 %, respectively, which displayed a significant difference (OR = 0.56, 95 % CI [0.32, 0.97], p = 0.04). Nevertheless, the recurrence rate of EMR was significantly higher than that of ESD (15.9 % vs 0.5 %) (OR = 23.06, 95 % CI [11.11, 47.85], p < 0.00001).

CONCLUSIONS

endoscopic resection of LSTs is safe and effective. As compared with EMR, ESD has higher en-bloc and complete resection rates but a lower recurrence rate. Therefore, ESD is highly recommended for the treatment of LSTs.

Treatment policy for colonic laterally spreading tumors based on each clinicopathologic feature of 4 subtypes: actual status of pseudo-depressed type

BACKGROUND AND AIMS

Laterally spreading tumors (LSTs) are originally classified into 4 subtypes. Pseudo-depressed nongranular types (LSTs-NG-PD) are gaining attention because of their high malignancy potential. Previous studies discussed the classification of nongranular (LST-NG) and granular types (LST-G); however, the actual condition or indication for endoscopic treatment of LSTs-NG-PD remains unclear. We aimed to compare the submucosal invasion pattern of LSTs-NG-PD with the other 3 subtypes.

METHODS

A total of 22,987 colonic neoplasms including 2822 LSTs were resected endoscopically or surgically at Showa University Northern Yokohama Hospital. In these LSTs, 322 (11.4%) were submucosal invasive carcinomas. We retrospectively evaluated the clinicopathologic features of LSTs divided into 4 subtypes. In 267 LSTs resected en bloc, their submucosal invasion site was further evaluated.

RESULTS

The frequency of LSTs in all colonic neoplasms was significantly higher in women (14.9%) than in men (11.0%). Rates of submucosal invasive carcinoma were .8% in the granular homogenous type (LSTs-G-H), 15.2% in the granular nodular mixed type (LSTs-G-M), 8.0% in the nongranular flat elevated type (LSTs-NG-F), and 42.5% in LSTs-NG-PD. Tumor size was associated with submucosal invasion rate in LSTs-NG-F and LSTs-NG-PD (P < .001). The multifocal invasion rate of LSTs-NG-PD (46.9%) was significantly higher than that of LSTs-G-M (7.9%) or LSTs-NG-F (11.8%). In LSTs-NG-PD, the invasion was significantly deeper (≥1000 μm) if observed in 1 site.

CONCLUSIONS

For LSTs-G-M and LSTs-NG-F that may have invaded the submucosa, en bloc resection could be considered. Considering that LSTs-NG-PD had a higher submucosal invasion rate, more multifocal invasive nature, and deeper invasion tendency, regardless if invasion was only observed in 1 site, than LSTs-NG-F, we should endoscopically distinguish LSTs-NG-PD from LSTs-NG-F and strictly adopt en bloc resection by endoscopic submucosal dissection or surgery for LSTs-NG-PD. (Clinical trial registration number: UMIN 000020261.).

Predicting and managing complications following colonoscopy: risk factors and management of advanced interventional endoscopy with a focus on colorectal ESD

INTRODUCTION

Colorectal endoscopic submucosal dissection (ESD) has been introduced widely in Western and Asian countries. The management of the perforation during ESD is crucial.

AREAS COVERED

The rate of intraprocedural perforation, risk factors, prevention, and management of perforation during ESD and EMR were discussed in this review. The perforation rate in ESD and EMR depending on the lesion size is also discussed.

EXPERT OPINION

The knowledge regarding the risk factor and techniques to manage perforation is important during colorectal ESD and EMR. The development of novel suturing techniques devices is key for colorectal ESD in the future.

Delayed perforation after endoscopic resection of a colonic laterally spreading tumor: A case report and literature review

BACKGROUND

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been widely used for the treatment of early gastrointestinal cancer. Endoscopic piecemeal mucosal resection (EPMR) is derived from the combination of EMR and ESD. Delayed perforation with peritonitis after colonic EPMR is a rare but severe complication, sometimes requiring surgery. There are some associated risk factors, including patient- (location, diameter, and presence of fibrosis) and procedure-related factors. Early recognition and timely treatment are crucial for its management.

CASE SUMMARY

We report a case in which delayed perforation with peritonitis was treated using endoscopic closure. A 54-year-old man was diagnosed with a 30-mm-diameter laterally spreading tumor in the colonic hepatic curvature. Fifteen hours after endoscopic resection, peritonitis caused by delayed perforation occurred and gradually aggravated. Conservative treatment was ineffective and no obvious perforation was observed. After timely endoscopic closure, the patient was discharged on postoperative day 4.

CONCLUSION

In occasion of localized peritonitis aggravating without macroscopic perforation, endoscopic closure is an effective treatment for delayed perforation with stable vital signs in the early stage.

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.

Endoscopic submucosal dissection involving the anal canal presents a risk factor for postoperative stricture

BACKGROUND

Although postoperative strictures after endoscopic submucosal dissection (ESD) in the rectum are relatively rare, some rectal lesions require resection involving the anal canal, which is a narrow tract comprising squamous epithelium. To the best of our knowledge, no studies have investigated narrow anal canals when evaluating post-ESD strictures. This study aimed to evaluate the impact of resections involving the anal canal on postoperative stricture development.

METHODS

Between April 2005 and October 2017, 707 rectal lesions were treated with ESD. We retrospectively investigated 102 lesions that required ≥ 75% circumferential resection. Risk factors for post-ESD stricture and, among patients with strictures, obstructive symptoms, and number of dilation therapies required were investigated.

RESULTS

Post-ESD stricture occurred in 18 of 102 patients (17.6%). In the multivariate analysis, circumferential resection ≥ 90% and ESD involving the anal canal (ESD-IAC) were risk factors for postoperative strictures (P ≤ 0.0001 and 0.0115, respectively). Among the patients with strictures, obstructive symptoms were significantly related to anal strictures compared to rectal strictures (100% vs. 27.2%, P = 0.0041). Furthermore, the number of dilation therapies required was significantly greater among patients with anal strictures compared to those with rectal strictures (6.5 times vs. 2.7 times, P = 0.0263).

CONCLUSION

Not only circumferential resection ≥ 90% but also ESD-IAC was a significant risk factor for the stricture after rectal ESD. Furthermore, anal strictures were associated with a significantly higher frequency of obstructive symptoms and larger number of required dilation therapies than were rectal strictures.

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

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

Endoscopic mucosal resection with an additional working channel (EMR+) in a porcine ex vivo model: a novel technique to improve en bloc resection rate of snare polypectomy

Background and study aims  Recently, a new external additional working channel (AWC) was introduced by which conventional endoscopic mucosal resection (EMR) can be improved to a technique termed "EMR+". We first evaluated this novel technique in comparison to classical EMR in flat lesions. Methods  The trial was prospectively conducted in an ex vivo animal model with porcine stomachs placed into the EASIE-R simulator. Prior to intervention, standardized lesions were set by coagulation dots, measuring 1, 2, 3 or 4 cm. Results  Overall, 152 procedures were performed. EMR and EMR+ were both very reliable in 1-cm lesions, each showing en bloc resection rates of 100 %. EMR+ en bloc resection rate was significantly higher in 2-cm lesions (95.44 % vs. 54.55 %, P  = 0.02), in 3-cm lesions (86.36 % vs. 18.18 %, P  < 0.01) and also in 4-cm lesions (60.00 % vs. 0 %, P  < 0.01). Perforations occurred only in EMR+ procedures in 4-cm lesions (3 of 20; 15 %). Conclusions  With its grasp-and-snare technique, EMR+ facilitates en bloc resection of larger lesions compared to conventional EMR. In lesions 2 cm and larger, EMR+ has demonstrated advantages, especially concerning en bloc resection rate. At 3 cm, EMR+ reaches its best discriminatory power whereas EMR+ has inherent limits at 4 cm and in lesions of that size, other techniques such as ESD or surgery should be considered.

EMR + with the AWC improves endoscopic resection speed compared to ESD: a porcine ex-vivo pilot study

INTRODUCTION

To improve resection speed and to reach higher en bloc resection rates in lesions ≥ 2 cm, a novel grasp and snare EMR technique termed "EMR+", accomplished by an additional working channel (AWC), was developed. Its use compared to endoscopic submucosal dissection (ESD) is evaluated for the first time.

MATERIAL AND METHODS

We prospectively conducted a randomized pre-clinical ex-vivo pilot study in explanted porcine stomachs for the comparison of EMR + with classical ESD of mucosal-based lesions. Prior to intervention, we set flat lesions with a standardized size of 3 × 3 cm.

RESULTS

The median time of procedure was significantly shorter in the EMR + group (median 10.5 min, range 4.4-24 min) than in the ESD group (median 32 min, range 14-61.6 min, p < .0001). The rate of en bloc resection was significantly lower in the EMR + group (38 % vs. 95 %) (p < .0001). Nevertheless, an improvement in the learning curve for EMR + was achieved after the first 12 procedures, with a subsequent en bloc resection rate of 100 %.

CONCLUSIONS

EMR + could improve the efficiency of mucosal resection procedures. Initial experience demonstrates a higher and satisfactory en bloc resection rate after going through the learning curve of EMR+.

Effect of Preceding Biopsy on the Results of Endoscopic Submucosal Dissection for Colorectal Laterally Spreading Tumor

BACKGROUND

Forceps biopsies are usually performed before endoscopic submucosal dissection (ESD) for colonic laterally spreading tumors (LSTs). However, preceding biopsy is commonly believed to possibly inhibit complete tumor resection by causing blurring of tumor borders and tissue fibrosis.

AIMS

The aims were to investigate whether the preceding biopsy of colorectal LST affects the complete endoscopic tumor resection and increases the risk of complications.

METHODS

We retrospectively reviewed the medical records of patients with colorectal LSTs who underwent ESD at our center during an 8-year period. Patients were divided into two groups according to whether they underwent biopsy of the tumor before ESD. In addition, the characteristics of patients and tumors, including the completeness of tumor resection, were investigated.

RESULTS

Of 288 patients (174 men) enrolled in this study, 194 (67.4%, preceding biopsy group) underwent biopsies before ESD, whereas 94 (32.6%, no biopsy group) did not. There were no significant differences in age, sex, comorbidity, medication history, tumor location, and final pathologic result between both groups. Tumor size was larger (p = 0.002) and LST-G tumor was more common (p = 0.003) in the preceding biopsy group than in the no biopsy group. No significant difference was seen in ESD outcomes, including procedure time, hospitalization period, incidence of complications, en bloc resection rate, resection margin status, and incidence of surgical operation, between both groups.

CONCLUSIONS

Biopsy of LST is commonly performed before endoscopic resection. Contrary to popular belief, it does not increase the incomplete tumor resection rate and incidence of complications.

TRIAL REGISTRATION

KCT0002321.

Effect of prophylactic endoscopic closure for an artificial ulceration after colorectal endoscopic submucosal dissection: a randomized controlled trial

Objective: Endoscopic submucosal dissection (ESD) is now commonly performed as a treatment for not only gastric tumor but also colorectal tumor. However, colorectal ESD has a substantial risk of complications, including post-ESD electrocoagulation syndrome, bowel perforation and bleeding. This study aimed to investigate whether prophylactic endoscopic closure can reduce the occurrence of complications after colorectal ESD.Materials and methods: Patients who underwent colorectal ESD in our unit were randomly assigned to either of two groups. Prophylactic endoscopic closure for an artificial ulceration after ESD was performed in group I but not in group II. After the procedure, the incidence of complications, visual analog scale (VAS) score for abdominal pain, and laboratory findings were investigated.Results: Of the 220 patients (110 per group) enrolled in this study, 137 were men. No significant differences were found in age, sex, comorbidity, medication history, tumor location, size of resected specimen, and pathologic result between the two groups. No significant difference was found in ESD outcomes, including hospitalization period, laboratory findings, VAS score for abdominal pain, incidence of surgical operation, and incidence of post-ESD complications, between the two groups.Conclusions: Contrary to popular belief, prophylactic endoscopic closure after colorectal ESD does not decrease the incidence of complications, and it does not ameliorate inflammatory response and abdominal pain.Clinical trial registration number: KCT0001666.

Construction of a preoperative scoring system to predict the difficulty level of colorectal endoscopic submucosal dissection

Background

We attempted to examine the factors contributing to the difficulty in performance of colorectal ESD, with the aim of constructing a scoring system that could help in prediction of the difficulty level of the procedure.

Methods and materials

The data were analyzed from two viewpoints: to determine the factors contributing to 1) non-en bloc resection and the factors contributing to 2) a slow resection speed. Factors falling under these two categories contributing to difficulty in performance of ESD were extracted and used to construct a scoring system. The validity of this scoring system was evaluated by calculating the correlation between the score and the resection speed in a different dataset.

Results

Based on the results of our analysis, we assigned scores for various factors as follows: 4 points for EMR of a scarred lesion, 1 point for tumors with a diameter of ≥ 30 mm, 2 points for lesions located in the liver/splenic flexure, 1 point for lesions located in the transverse colon, 3 points for LST-NG-PD/depressed lesions, 1 point for protruded lesions and LST-NG-F lesions (range 0–10). In the validation study, the rank correlation coefficient between the score according to the scoring system and the resection speed was -0.130, representing a weak and negative correlation (P = 0.03). We defined the difficulty level depending on the sum of the scores: 0–2, low difficulty level; 3–5, intermediate difficulty level; ≥ 6, high difficulty level. The average resection speed was 12.6 mm²/min in the group with scores of 0–2, 8.1 mm²/min in the group with scores of 3–5, and 5.5 mm²/min in the group with scores of ≥ 6 (11.2 mm²/min in all lesions).

Conclusion

Our colorectal ESD scoring system would be useful for selection of operators with the appropriate skill level in the procedure for colorectal ESD cases.

Endoscopic submucosal dissection with a novel high viscosity injection solution (LiftUp) in an ex vivo model: a prospective randomized study

Introduction  Endoscopic submucosal dissection (ESD) is increasingly being used in the western world. Submucosal injectates are an essential tool for the ESD procedure. In this study, we evaluated a novel copolymer injectate (LiftUp, Ovesco, Tübingen Germany) in an established ESD model (EASIE-R) in comparison to existing submucosal injectables. Materials and methods  We conducted a prospective, randomized ex vivo study performing ESD with three injectates: LiftUp, hydroxyethyl starch (HAES 6 %) and normal saline solution (NaCl 0.9 %). A total of 60 artificial lesions, each 3 × 3 cm in size, were resected in an ex vivo porcine model, utilizing one of the three studied injectates (n = 20 ESDs per injectate). Study parameters were: en bloc resection rate, perforation rate, lifting property, time of injection, injectate volume, general ESD procedure time, and overall procedure time. Results  All 60 lesions were successfully resected using the standard ESD technique. LiftUp had no procedure related perforations, one perforation occurred in the HAES group, and two perforations in the NaCl group ( P  > 0.05). Furthermore, adequate lifting was achieved in 16/20 (80 %) using LiftUp, 6/20 (30 %) in the HAES group and 6/20 (30 %) in the NaCl group ( P  < 0.0002). En bloc resection was achieved in 19 (95 %) with LiftUp, in 20 (100 %) with HAES, and in 16 (80 %) with NaCl. General ESD procedure time and overall procedure time were not different among the three groups. Conclusion  LiftUp appears to be a safe alternative to established fluids for ESD. It had a significantly improved lifting effect and required significantly less injected volume compared to well-established lifting solutions.

Optimal processing of ESD specimens to avoid pathological artifacts

BACKGROUND

En bloc endoscopic submucosal dissection (ESD) has been recently introduced as a treatment for precancerous/neoplastic gastrointestinal conditions. The aim of the present study was histological assessment of en bloc ESD specimens.

METHODS

Fifty-three ESD specimens were positioned over a cellulose acetate support (40 specimens; 12 from the upper gastrointestinal tract and 28 from the lower gastrointestinal tract) or pinned with nails on polystyrene or cork (13 specimens; 7 from the upper gastrointestinal tract and 6 from the lower gastrointestinal tract). We cut consecutive 2 mm-thick sections stained with hematoxylin and eosin. From the first and the last sections, we obtained a second slide, after a 180° rotation and re-embedding. The quality of ESD samples was scored as inadequate, suboptimal and adequate, based on the amount of crushing, shearing and stretching artifacts that were scored from 0 (absent) to 2 (diffuse or maximum). From the sum of these we obtained a global artifact score (GAS).

RESULTS

Removed lesions were: adenocarcinoma (5 cases), neuroendocrine tumor (NET) G1 (1 case), premalignant conditions, including adenomatous polyps (41 cases) and hyperplastic lesions (6 cases). A positive deep surgical margin was found in 8/53 cases (15%): high- and low-grade dysplastic glands were detected in 5 cases, low-grade adenocarcinoma in 2, and NET cells in 1. Dysplastic glands were detected in the lateral surgical margins of 12 ESD specimens (23%). Among the ESD specimens positioned on the cellulose acetate support, apart from the modifications due to electrocoagulation, 2 (5%) showed shearing modifications. In the group of ESD specimens fixed with nails, 5 (38%) showed shearing, 10 (77%) crushing artifacts, 11 (85%) stretching and 11 (85%) multiple holes caused by the nails. On the basis of these data all histological specimens from ESD on cellulose acetate were adequate (GAS 0-1).However, in the group of ESD fixed with nails, 1 was adequate (GAS 0), 11 suboptimal (GAS 2-5) and 1 inadequate (GAS 6).

CONCLUSIONS

Specific devices including cellulose support and adequate sampling blocks can be helpful to perform accurate histological assessment of ESD specimens after en bloc ESD for precancerous/neoplastic gastrointestinal lesions, with complete analysis of the status of the margins and the entirely en bloc evaluation of the lesion.

Laparoscopic and endoscopic cooperative surgery (LECS) to overcome the limitations of endoscopic resection for colorectal tumors

Background and study aims  We developed a laparoscopy endoscopy cooperative surgery (LECS) to overcome the limitations of endoscopic resection for colorectal tumors. The aim of this study was to evaluate the feasibility of LECS, which combines endoscopic submucosal dissection (ESD) and laparoscopic partial colectomy. Patients and methods  We performed LECS for 17 colorectal tumors in 17 patients (male:female 10:7; mean age, 66.5 years). The clinicopathological outcomes of these 17 cases and the feasibility of LECS were evaluated retrospectively. Indications for LECS were as follows: 1) intramucosal cancer and adenoma accompanied by wide and severe fibrosis; 2) intramucosal cancer and adenoma involving the diverticulum or appendix; and 3) submucosal tumors. Results  We successfully performed LECS procedures in 17 cases (intramucosal cancer [n = 6], adenoma [n = 9], schwannoma [n = 1], and gastro-intestinal stromal tumour [GIST] [n = 1]. Mean tumor diameter was 22.4 mm (range, 8 - 41 mm). LECS was successfully performed in all 17 cases without conversion to open surgery; the R0 rate was 100 %. LECS was applied to the following situations: involving the appendix (n = 6), tumor accompanied by severe fibrosis (n = 5), involving the diverticulum (n = 3), submucosal tumor (n = 2), and poor endoscopic operability (n = 1). We experienced no adverse events (e. g., leakage or anastomotic stricture) and the median hospital stay was 6.4 dayus (range, 4 to 12). All 17 patients who were followed for ≥ 3 months (median, 30.8 months; range, 3 - 72 months) showed no residual/local recurrence. Conclusion  LECS was a safe, feasible, minimally invasive procedure that achieved full-thickness resection of colorectal tumors and showed excellent clinical outcomes.

The relationship between local recurrence and positive lateral margin after en bloc resection of colorectal neoplasm

BACKGROUND

The factors associated with recurrence of colonic neoplasm after endoscopic resection with a positive lateral margin are not well known. Thus, we evaluate the relationship between recurrence and positive lateral margin after endoscopic en bloc resection of colorectal neoplasm.

METHODS

A retrospective review of 9302 patients who underwent colonic endoscopic resection from January 2008 to January 2015. Of these, a total of 76 patients with positive lateral margins with clear evidence of the its location on endoscopic picture after endoscopic en bloc resection of colorectal neoplasm (>10 mm) were included.

RESULTS

Ten of 76 (13.2%) patients experienced recurrence during the follow-up period (mean f/u month, 21.7 ± 15.6). In cases with positive lateral margins, the 3- and 5-year local recurrence rate of colorectal neoplasm was 28.1% and 40.1%, respectively. The histological features of the recurrence group were as follows: one case of adenocarcinoma [from low-grade adenoma (LGA)]; two cases of high-grade adenoma (HGA) (one from HGA and one from LGA); and seven cases of LGA (four from adenocarcinoma, two from LGA, and one from HGA). The mean age of patients, locations of the lesions, and histologic type were not significantly associated with local recurrence. In multivariate Poisson regression analyses, total length of lateral margin involvement ≥8 mm (relative risk 12.51; 95% CI 1.11-140.34, p = .040) was a significant predictor of local recurrence.

CONCLUSIONS

Positive lateral margins ≥8 mm may be a reliable predictor of local recurrence after endoscopic en bloc resection of colorectal neoplasm.

Why attempt en bloc resection of non-pedunculated colorectal adenomas? A systematic review of the prevalence of superficial submucosal invasive cancer after endoscopic submucosal dissection

OBJECTIVE

Endoscopic submucosal dissection (ESD) aims to achieve en bloc resection of non-pedunculated colorectal adenomas which might be indicated in cases with superficial submucosal invasive cancers (SMIC), but the procedure is time consuming and complex. The prevalence of such cancers is not known but may determine the clinical necessity for ESD as opposed to the commonly used piecemeal mucosal resection (endoscopic mucosal resection) of colorectal adenomas. The main aim was to assess the prevalence of SMIC SM1 (ie, invasion ≤1000 µm or less than one-third of the submucosa) on colorectal lesions removed by ESD.

DESIGN

A literature review was conducted using electronic databases (up to March 2017) for colorectal ESD series reporting the histology of the dissected lesions.

RESULTS

51 studies with data on 11 260 colorectal dissected lesions were included. Most resected lesions (82.2%; 95% CI 78.8% to 85.3%) were adenomas (low- and high-grade dysplasia, 26.8% and 55.4%, respectively). Overall, 15.7% were submucosal cancers, but only slightly more than half (8.0%; 95% CI 6.1% to 10.3%) had an infiltration depth of ≤1000 µm, providing a number needed to treat (NNT) to avoid one surgery of 12.5. Estimating an oncologically curative (R0; G1/2; L0/V0) resection rate of 75.3% (95% CI 52.2% to 89.4%) for malignant lesions, the prevalence of curative resection lowered to 6% (95% CI 4.2% to 7.2%) with an NNT of 16.7.

CONCLUSION

The low prevalence of SMIC SM1 in lesions selected for ESD as well as the even lower rate of curative resection limits the clinical applicability of endoscopic en bloc resection. This calls for caution over an indiscriminate use of this technique in the resection of colorectal neoplasia.

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.

Carbon dioxide insufflation during endoscopic resection of large colorectal polyps can reduce post-procedure abdominal pain: A prospective, double-blind, randomized controlled trial

Background

Studies of the use of CO₂ insufflation during endoscopic resection of large colorectal polyps (LCPs) are lacking.

Objective

We evaluated the effect of CO₂ insufflation on pain after endoscopic resection of LCPs.

Methods

In a prospective randomized controlled trial (RCT), 132 patients were randomly assigned to groups who underwent endoscopic resection with CO₂ insufflation (CO₂ group, n = 66) or air insufflation (air group, n = 66). The primary outcome was abdominal pain post-procedure (PP). The secondary outcomes were abdominal distension, rates of technical success, amounts of sedatives prescribed, use of analgesics, and adverse events.

Results

Baseline patient characteristics were similar between the groups. The mean abdominal pain score was 12.3 in the CO₂ group vs. 17.5 in the air group at 1 h PP (p  =  0.047). Also, the proportion of patients without pain was significantly higher in the CO₂ group at 1 h PP (p = 0.008). The pain score differed more in the endoscopic submucosal dissection group and long-time group. The secondary outcomes were not significantly different between the two groups.

Conclusions

The results of this RCT demonstrate the superiority of CO₂ insufflation for endoscopic resection of LCPs in terms of decreasing PP abdominal pain (KCT0001636).

Short-term outcomes of endoscopic submucosal dissection for superficial cecal tumors: a comparison between extension and nonextension into the appendiceal orifice

BACKGROUND

Few studies have investigated the use of endoscopic submucosal dissection (ESD) for cecal tumors extending into the appendiceal orifice. Herein, we assessed the feasibility and safety of ESD for cecal tumors extending into the appendiceal orifice.

METHODS

We retrospectively examined the outcomes of ESD for 78 patients with 78 cecal tumors (male/female ratio, 40/38; mean [standard deviation, SD] age, 67 [9] years; mean [SD] tumor size, 32 [15] mm), who underwent ESD at the Hiroshima University Hospital between October 2008 and March 2016. The indication for ESD in cecal tumors extending into the appendiceal orifice was recognition of the distal edge of the lesion in the appendix. They were classified into two groups: patients with cecal tumors extending (Group A: 29 patients, 29 tumors) and not extending (Group B: 49 patients, 49 tumors) into the appendiceal orifice. We compared the outcomes of ESD between both groups.

RESULTS

No significant differences in clinicopathological characteristics were observed between both groups. The rate of severe submucosal fibrosis in Group A (48%) was significantly higher than that in Group B (24%) (p < 0.05). The mean (SD) procedure speed in Group A (14 [10] mm²/min) was significantly slower than that in Group B (23 [16] mm²/min) (p < 0.01). The en bloc resection rates in Groups A and B were 90% and 96%, respectively. There were no significant differences in adverse events reported between both groups.

CONCLUSIONS

ESD for cecal tumors with extension into the appendiceal orifice is effective and safe.

Clinical outcomes of endoscopic submucosal dissection for colorectal tumors: a large multicenter retrospective study from the Hiroshima GI Endoscopy Research Group

BACKGROUND AND AIMS

Although advanced high-volume centers have reported good outcomes of colorectal endoscopic submucosal dissection (ESD), a limited number of highly skilled experts in specialized institutions performed these procedures. We undertook a retrospective multicenter survey, which included nonspecialized hospitals, to investigate the clinical outcomes of colorectal ESD.

METHODS

We recruited 1233 consecutive patients with 1259 colorectal tumors resected by ESD at 12 institutions. We evaluated the en bloc resection rate, histologic complete resection rate, curative (R0) resection rate, adverse events, and the long-term prognoses, including local recurrence, metachronous tumor development, and survival rate.

RESULTS

The en bloc, histologic complete, and R0 resection rates were 92.6%, 87.4%, and 83.7%, respectively. The delayed bleeding, intraoperative perforation, and delayed perforation rates were 3.7%, 3.4%, and .4%, respectively. The long-term outcomes analysis included 1091 patients (88.4%). Local recurrences occurred in 1.7%, and metachronous tumors (>5 mm) developed in 11.0% of the patients. The 3- and 5-year overall survival rates were 95.1% and 92.3%, respectively. The number of colonic tumors, severe submucosal fibrosis, and en bloc resection rates were significantly higher in the high-volume centers (Group H) than those in the low-volume centers (Group L). The average tumor size in Group H was significantly larger than that in Group L.

CONCLUSIONS

Colorectal ESDs are feasible, have acceptable adverse event risks, and favorable long-term prognoses. (Clinical trial registration number: UMIN000016197.).

Clinical outcomes of endoscopic submucosal dissection for large colorectal laterally spreading tumors in older adults

BACKGROUND AND AIMS

The colorectal endoscopic submucosal dissection (ESD) remains technically challenging, especially for older patients who frequently encounter complex chronic diseases and have a loose colon. However, only limited number of studies are available for the safety of ESD in older patients with especially large laterally spreading tumors. Therefore, in this retrospective study, we compared the outcomes of ESD for laterally spreading tumors (LST) ≥3cm(cm) in older patients to that in younger patients.

METHODS

Consecutive patients with LSTs 3cm or larger were enrolled for from May 2010-2016. These patients were divided into two groups: the younger group (<65years) and the older group (≥65years). The clinicopathologic findings and the outcomes of ESD procedures were compared between the two groups.

RESULTS

A total of 70 patients in the younger group and 73 patients in the older group were treated by ESD for colorectal LSTs larger than 3cm. No significant differences were observed in the gender ratio, tumor morphological type, tumor location, and tumor size between the two groups. The en bloc resection rates were 85.7 and 89.0%, respectively, without a significant difference. The procedural time was similar between the younger and older patients (71.8±34.7min vs. 70.6±29.5min). The duration of hospital stay was not significantly different between the two groups (4.1±2.2days vs. 4.4±2.5days). No significant differences were observed between the two groups with respect to ESD-related complications including delayed bleeding, perforation, and stricture.

CONCLUSIONS

ESD appears to be an effective and safe method for LSTs larger than 3cm in older patients.