Preoperative indicators of failure of en bloc resection or perforation in colorectal endoscopic submucosal dissection: implications for lesion stratification by technical difficulties during stepwise training

Outcomes in colorectal endoscopic submucosal dissection for large protruded lesions: A retrospective multicenter study

Background and study aims Colorectal endoscopic submucosal dissection (ESD) is increasingly used for treating early-stage colorectal cancer, including large, protruded lesions (LPL). However, the challenges posed by LPLs, especially those accompanied by severe fibrosis or muscle-retracting sign (MRS), remain unclear. This study aims to investigate ESD outcomes for LPL, focusing on factors such as tumor size and, submucosal fibrosis. Patients and methods In a multicenter retrospective study (June 2012 to May 2023), data from 526 patients with 542 LPL lesions (≥ 2 cm) were analyzed. Parameters included lesion size, procedure time, dissection speed, physician experience, submucosal fibrosis, and adverse events. The tunnel method, including the double tunnel method, was used for cases with severe fibrosis or MRS. Multivariate analysis assessed factors affecting procedure difficulty, particularly LPLs ≥ 4 cm. Results The study revealed an impressive en bloc resection rate of 97.8% and a curative resection rate of 78.6% for LPLs. Notably, fibrosis and MRS were present in 25% and 18% of 4-cm LPLs, respectively, and their frequency tended to increase as the tumor diameter increased. One treatment strategy for LPLs was the tunneling method, which was used most frequently (41 cases, 7.6%). Factors affecting dissection speed included larger tumor size, submucosal fibrosis, MRS, and physician experience. Conclusions Treating LPLs through colorectal ESD presents significant challenges, especially in patients with fibrosis and MRS. This study highlights the importance of recognizing these complexities, and that more reliable resection strategy must be established for accurate pathological evaluation.

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.

Predictive factors associated with technical difficulty in colorectal endoscopic submucosal dissection: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study

Colorectal endoscopic submucosal dissection (ESD) is a promising but challenging procedure. It is not widely performed due to its technical difficulty. We aimed to find the predictive factors associated with technical difficulty in colorectal ESD before the procedure. Clinical data from patients who underwent ESD for colorectal tumors in 5 hospitals in Honam province of South Korea between 2015 and 2020 were reviewed retrospectively. Technically difficult colorectal ESD procedure was defined in 3 points. Long procedure time (longer than 60 minutes), occurrence of perforation, and failure of en bloc resection. Factors associated with technically difficult ESD were included as main outcome measure. 1446 patients were identified and their data were analyzed. Median procedure time was 30.0 minutes and median long axis of the tumor was 20.1 mm. Technically difficult procedures including long procedure time were 231 cases (16.0%), perforation occurred in 34 cases (2.3%), and en bloc resection was done in 1292 cases (89.3%). Tumor size larger than 35 mm (odd ratio [OR]: 1.474, P = .047), central depression or ulceration in the lesion (OR: 1.474, P = .013), previous endoscopic mucosal resection (EMR) or polypectomy procedure (OR: 2.428, P = .020) were associated with technically difficult ESD. Descending colon-located tumor (OR: 5.355, P < .001), and use of IT knife (OR: 4.157, P = .003) were associated with perforation. Recognizing factors associated with technically difficult ESD can help in planning the ESD procedure beforehand.

Clinical outcomes and learning curve of Tip-in endoscopic mucosal resection for 15-25 mm colorectal neoplasms among non-experts

BACKGROUND AND AIM

Tip-in endoscopic mucosal resection (EMR) has a high en bloc resection rate for large colorectal neoplasms. However, non-experts' performance in Tip-in EMR has not been investigated. We investigated whether Tip-in EMR can be achieved effectively and safely even by non-experts.

METHODS

This retrospective study included consecutive patients who underwent Tip-in EMR for 15-25 mm colorectal nonpedunculated neoplasms at a Japanese tertiary cancer center between January 2014 and December 2020. Baseline characteristics, treatment outcomes, learning curve of non-experts, and risk factors of failing self-achieved en bloc resection were analyzed.

RESULTS

A total of 597 lesions were analyzed (438 by experts and 159 by non-experts). The self-achieved en bloc resection (69.8% vs 88.6%, P < 0.001) and self-achieved R0 resection (58.3% vs 76.5%, P < 0.001) rates were significantly lower in non-experts with <10 cases of experience than in experts, but not in non-experts with >10 cases. Adverse event (P = 0.165) and local recurrence (P = 0.892) rates were not significantly different between experts and non-experts. Risk factors of failing self-achieved en bloc resection were non-polypoid morphology (OR 3.4, 95% CI 1.6-7.3, P = 0.001), lesions with an underlying semilunar fold (OR 3.6, 95% CI 1.6-7.3, P < 0.001), positive non-lifting sign (OR 3.1, 95% CI 1.2-8.0, P = 0.023), and non-experts with an experience of ≤10 cases (OR 3.6, 95% CI 2.1-6.3, P < 0.001).

CONCLUSION

The clinical outcomes of Tip-in EMR for 15-25 mm lesions performed by non-experts were favorable.

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.

Validation and update of a clinical score model to predict technical difficulty of colorectal endoscopic submucosal dissection: a multicenter prospective cohort study

BACKGROUND AND AIMS

The Zhongshan colorectal endoscopic submucosal dissection (CR-ESD) score model was proposed to grade the technical difficulty of CR-ESD. The objective of this study was to prospectively validate and update the score model.

METHODS

A multicenter prospective cohort analysis of CR-ESD was conducted. Individual data on patients, lesions, and outcomes of CR-ESD were used to validate the original model and further refine the difficulty of the prediction model. Data were randomly divided into discovery and internal validation cohorts. A multivariate Cox regression analysis was conducted on the discovery cohort to develop an updated risk-scoring system, which was then validated.

RESULTS

Five hundred forty-eight patients with 565 colorectal lesions treated by ESD from 4 hospitals were included. In the prospective validation cohort, the area under the receiver-operating characteristic (ROC) curve for the original model was .707. Six risk factors were identified and assigned point values: tumor size (2 points for 30-50 mm, 3 points for ≥50 mm), at least two-thirds circumference of the lesion (3 points), tumor location in the cecum (2 points) or flexure (2 points), laterally spreading tumor-nongranular lesions (1 point), preceding biopsy sampling (1 point), and NBI International Colorectal Endoscopic type 3 (3 points). The updated model had an area under the ROC curve of .738 in the discovery cohort and of .782 in the validation cohort. Cases were categorized into easy (score = 0-1), intermediate (score = 2-3), difficult (score = 4-6), and very difficult (score ≥7) groups. Satisfactory discrimination and calibration were observed.

CONCLUSIONS

The original model achieved an acceptable level of prediction in the prospective cohort. The updated model exhibited superior performance and can be used in place of the previous version. (Clinical trial registration number: ChiCTR2100047087.).

Efficacy of endoscopic submucosal resection with a ligation device for small rectal neuroendocrine tumor: study protocol of a multicenter open-label randomized control trial (BANDIT trial)

BACKGROUND

Endoscopic resection is widely accepted as a local treatment for rectal neuroendocrine tumors sized ≤ 10 mm. However, there is no consensus on the best method for the endoscopic resection of rectal neuroendocrine tumors. As a simplified endoscopic procedure, endoscopic submucosal resection with a ligation device (ESMR-L) indicates a histologically complete resection rate comparable to that of endoscopic submucosal dissection (ESD). We hypothesized that ESMR-L than ESD would be preferred for rectal neuroendocrine tumors. Hence, this trial aimed to verify whether ESMR-L is non-inferior to ESD in terms of histologically complete resection rate.

METHODS

This is a prospective, open-label, multicenter, non-inferiority, randomized controlled trial of two parallel groups, conducted at the Shizuoka Cancer Center and 31 other institutions in Japan. Patients with a lesion endoscopically diagnosed as a rectal neuroendocrine tumor ≤ 10 mm are eligible for inclusion. A total of 266 patients will be recruited and randomized to undergo either ESD or ESMR-L. The primary endpoint is the rate of en bloc resection with histologically tumor-free margins (R0 resection). Secondary endpoints include en bloc resection rate, procedure time, adverse events, hospitalization days, total devices and agents cost, adverse event rate between groups with and without resection site closure, outcomes between expert and non-expert endoscopists, and factors associated with R0 resection failure. The sample size is determined based on the assumption that the R0 resection rate will be 95.2% in the ESD group and 95.3% in the ESMR-L group, with a non-inferiority margin of 8%. With a one-sided significance level of 0.05 and a power of 80%, 226 participants are required. Assuming a dropout rate of 15%, 266 patients will be included in this study.

DISCUSSION

This is the first multicenter randomized controlled trial comparing ESD and ESMR-L for the R0 resection of rectal neuroendocrine tumors ≤ 10 mm. This will provide valuable information for standardizing endoscopic resection methods for rectal neuroendocrine tumors.

TRIAL REGISTRATION

Japan Registry of Clinical Trials, jRCTs042210124. Registered on Jan 6, 2022.

A nomogram for predicting the risk of postoperative fever in elderly patients undergoing endoscopic submucosal dissection of the upper gastrointestinal tract

To explore the risk factors of postoperative fever in elderly patients undergoing endoscopic submucosal dissection (ESD). A total of 439 patients who met the inclusion criteria were enrolled in this study and randomly divided into training (n = 311) and validation (n = 128) cohorts at a ratio of 7:3. Independent risk factors were screened by single-factor and multiple-factor logistic regression analyses, and a nomogram was established using them. The nomogram was evaluated using receiver operating characteristic curve analysis, decision curve analysis, and calibration plot using the "rms" package in R software (R4.2.1). The study included 439 patients. Female (OR = 2.55, 95% CI: 1.5-4.33), diabetes (OR = 2.38, 95% CI: 1.17-4.85), operation time (OR = 1.01, 95% CI: 1-1.02) were lesion located in the esophagus (OR = 2.37, 95% CI: 1.44-3.88), maximum tumor diameter (OR = 1.3, 95% CI: 1.07-1.57), and placement of a urinary catheter (OR = 7.09, 95%CI: 1.43-35.17) were independent risk factors for postoperative fever in elderly ESD patients (P < .05). Female sex, diabetes, lesions located in the esophagus, lesion size, operation time, and placement of a urinary catheter are risk factors for postoperative fever in ESD patients, and patients with these risk factors should be vigilant for postoperative fever and receive appropriate treatment.

Predictive Factors for the Outcome of Unsupervised Endoscopic Submucosal Dissection During the Initial Learning Curve with Prevalence-Based Indication

BACKGROUND

For an adequate educational strategy of ESD in non-Asian settings with prevalence-based indication it is essential to define adequate lesions, suitable for the beginner without on-site expert-supervision.

AIMS

We analyzed possible predictors for outcome parameters of effectiveness and safety during the initial learning curve.

METHODS

The first 120 ESDs of four operators (n = 480), performed between 2007 and 2020 in four tertiary hospitals, were enrolled. Uni-/multivariable regression analysis was done with sex, age, pretreated lesion, lesion size, organ, and organ-based localization as possible independent predictors for en bloc resection (EBR), complication, and resection speed.

RESULTS

Rates of EBR, complication, and resection speed were 84.5%, 14.2%, and 6.20 (± 4.45) cm2/h. Independent predictors for EBR were pretreated lesion (OR 0.27 [0.13-0.57], p < 0.001) and non-colonic ESD (OR 2.29 [1.26-4.17] (rectum)/5.72 [2.36-13.89] (stomach)/7.80 [2.60-23.42] (esophagus), p < 0.001), for complication pretreated lesion (OR 3.04 [1.46-6.34], p < 0.001) and lesion size (OR 1.02 [1.004-1.04], p = 0.012) and for resection speed pretreated lesion (RC - 3.10 [- 4.39 to - 1.81], p < 0.001), lesion size (RC 0.13 [0.11-0.16], p < 0.001) and male patient (RC - 1.11 [- 1.85 to - 0.37], p < 0.001). We found no significant difference in the incidence of technically unsuccessful resections in esophageal (1/84), gastric (3/113), rectal (7/181), and colonic (3/101) ESDs (p = 0.76). Technical failure was mainly caused by complication and fibrosis/pretreatment.

CONCLUSION

During the initial learning curve of an unsupervised ESD program with prevalence-based indication, pretreated lesions and colonic ESDs should be avoided. In contrast, lesion size and organ-based localizations have less predictive value for the outcome.

Factors associated with increased duration of endoscopic submucosal dissection for rectal tumors: a 22-year retrospective analysis

BACKGROUND AND AIMS

Colorectal endoscopic submucosal dissection (ESD) is widely used in several countries. However, it is associated with technical difficulties. Rectal ESD is considered an intermediate step in colorectal ESD training. Nevertheless, some rectal lesions require a longer procedure time than usual, and the reason for the prolonged time taken for these specific lesions remains unclear. Therefore, this study aimed to clarify the factors associated with prolonged rectal ESD.

METHODS

In total, 483 rectal lesions resected using ESD from February 1998 to June 2021 were investigated. Prolonged ESD procedure time was defined as the time from the first submucosal injection to lesion removal exceeding 120 minutes, whereas other procedures were defined as average ESD procedure time. Clinicopathologic and endoscopic findings were compared between the 2 groups using univariate and multivariate analyses.

RESULTS

One hundred forty-four lesions were resected using a prolonged ESD procedure time of 202.9 ± 92.3 minutes, whereas 339 lesions were resected using an average ESD procedure time of 77.8 ± 29.4 minutes. Multivariate analysis revealed that tumors involving the dentate line (P = .026), resection size ≥50 mm (P < .001), invasion depth ≥T1b (P = .006), and circumferential range ≥2/3 (P = .001) were independent risk factors for prolonged-duration ESDs, regardless of whether the procedure was performed by an expert or not.

CONCLUSIONS

The results of the present study suggest that the location of a lesion involving the dentate line, resection size ≥50 mm, circumferential range ≥2/3, and invasion depth ≥T1b are the independent risk factors for prolonged ESD procedure time.

Effectiveness of water pressure method in colorectal endoscopic submucosal dissection by novice endoscopists

Background and study aims Colorectal endoscopic submucosal dissection (ESD) remains challenging for novice endoscopists. Not only the underwater conditions but also active use of water pressure with the water pressure method (WPM) can help widen the submucosal layer. This study aimed to clarify the usefulness of WPM in colorectal ESD, especially for novice endoscopists. Methods This study was ex vivo and enrolled three novices. Each endoscopist performed conventional ESD (C-ESD) and ESD with WPM (WPM-ESD) 10 times on an excised bovine rectum. The treatment outcomes were compared between the two groups. Results Median procedure time was significantly shorter in the WPM-ESD group than in the C-ESD group (54 minutes, interquartile range [IQR] 42-67 vs. 45 minutes, IQR 34-55, P  = 0.035). Although no significant difference in the activation time of electrical surgical unit (ESU) during the procedure was noted, the interval time during the procedure at which the ESU was not activated was significantly shorter in the WPM-ESD group (52 minutes, IQR 40-65 vs. 42 minutes, IQR 32-52, P  = 0.030) than in the C-ESD group. Moreover, the time required for the endoscope to enter the submucosa was significantly shorter in the WPM-ESD group than in the C-ESD group (8.0 minutes, IQR 6.0-10 vs. 5.0 minutes, IQR 3.0-6.0, P  < 0.001). Conclusions The present study reveals that the WPM method significantly shortens the procedure times for novices in colorectal ESD, especially the interval time, which refers to the time spent creating the field of view, and the time required for the endoscope to enter the submucosa.

Endoscopic submucosal dissection techniques and technology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Review

ESGE suggests conventional endoscopic submucosal dissection (ESD; marking and mucosal incision followed by circumferential incision and stepwise submucosal dissection) for most esophageal and gastric lesions. ESGE suggests tunneling ESD for esophageal lesions involving more than two-thirds of the esophageal circumference. ESGE recommends the pocket-creation method for colorectal ESD, at least if traction devices are not used. The use of dedicated ESD knives with size adequate to the location/thickness of the gastrointestinal wall is recommended. It is suggested that isotonic saline or viscous solutions can be used for submucosal injection. ESGE recommends traction methods in esophageal and colorectal ESD and in selected gastric lesions. After gastric ESD, coagulation of visible vessels is recommended, and post-procedural high dose proton pump inhibitor (PPI) (or vonoprazan). ESGE recommends against routine closure of the ESD defect, except in duodenal ESD. ESGE recommends corticosteroids after resection of  > 50 % of the esophageal circumference. The use of carbon dioxide when performing ESD is recommended. ESGE recommends against the performance of second-look endoscopy after ESD. ESGE recommends endoscopy/colonoscopy in the case of significant bleeding (hemodynamic instability, drop in hemoglobin > 2 g/dL, severe ongoing bleeding) to perform endoscopic hemostasis with thermal methods or clipping; hemostatic powders represent rescue therapies. ESGE recommends closure of immediate perforations with clips (through-the-scope or cap-mounted, depending on the size and shape of the perforation), as soon as possible but ideally after securing a good plane for further dissection.

Endoscopic submucosal dissection for tumors involving the ileocecal valve with extension into the terminal ileum: a multicenter study from the Hiroshima GI Endoscopy Research Group

BACKGROUND

The efficacy and safety of endoscopic submucosal dissection (ESD) for tumors extending into the terminal ileum remain obscure. We aimed to evaluate the outcomes of ESD for tumors involving the ileocecal valve (ICV) with extension into the terminal ileum.

METHODS

Sixty-eight patients (40 men; mean age, 67 years) with 68 tumors involving the ICV that were resected by ESD between December 2013 and December 2018 were included and classified into Group A (21 tumors with extension into the terminal ileum) and Group B (47 tumors without extension). ESD outcomes were compared between groups.

RESULTS

The clinical features of the patients and tumors were not significantly different between the groups. There were no significant differences in en bloc resection rate (95% and 94%, respectively; p = 0.79), R0 resection rate (90% and 89%, respectively; p = 0.89), procedure time (95 ± 54 min and 94 ± 69 min, respectively; p = 0.64), postoperative bleeding rate (5% and 3%, respectively; p = 0.79), intraoperative perforation rate (0% and 4%, respectively; p = 0.34), delayed perforation rate (0% and 0%, respectively), or postoperative symptomatic stenosis rate (0% and 0%, respectively) between Groups A and B. No specific factors related to the outcomes of ESD were found by subgroup analysis according to the dominance and degree of circumference of the ICV. Local recurrence was observed in 1 patient in Group A who was retreated using ESD.

CONCLUSIONS

ESD for tumors involving the ICV with extension into the terminal ileum is safe and effective.

Conventional versus hybrid knife endoscopic submucosal dissection in large colorectal laterally spreading tumors: A propensity score analysis

BACKGROUND

Colorectal endoscopic submucosal dissection (CR-ESD) has become a promising treatment for laterally spreading tumors (LSTs), but is accompanied by great challenges.

.

This study aimed to evaluate the efficacy and safety of CR-ESD with a hybrid knife, versus the conventional technique for LSTs ≥30 mm in diameter, and analyze the risk factors for piecemeal resection and perforation.

METHODS

Patients eligible for CR-ESD were divided into two groups according to the use of the hybrid knife (HK group) or the use of the conventional technique, with an interchange of injection and hook knife (C-group). We performed propensity score matching (PSM) to compare the HK group and the C-group. Risk predictors for perforation and piecemeal resection were identified.

RESULTS

PSM identified 61 (132 patients) and 61 (129 patients) patients in the C-group and the HK group, respectively. Resection speed was significantly faster in the HK group than in the C-group (18.86 vs. 13.33 mm²/min, P < 0.001). The rate of knife exchange was significantly lower in the HK group than in the C-group (1.6% vs. 49.2%, P < 0.001). Multivariate analysis revealed that unfavorable locations, including the splenic flexure, hepatic flexure, or cecum, were predictive of piecemeal resection. The presence of severe fibrosis and a semilunar fold were independent risk factors for perforation.

CONCLUSIONS

: The use of a hybrid knife appears to increase CR-ESD resection speed. The indicators for piecemeal resection or perforation in CR-ESD identified herein might help to assess the technical difficulties of CR-ESD.

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.

Tip-in EMR as an alternative to endoscopic submucosal dissection for 20- to 30-mm nonpedunculated colorectal neoplasms

BACKGROUND AND AIMS

Tip-in EMR, which includes anchoring the snare tip, has recently shown a favorable en-bloc and R0 resection rate for colorectal neoplasms. Thus, Tip-in EMR may be an alternative to endoscopic submucosal dissection (ESD). We aimed to compare clinical outcomes between Tip-in EMR and ESD for large colorectal neoplasms.

METHODS

This retrospective study evaluated consecutive patients who underwent Tip-in EMR or ESD for 20- to 30-mm nonpedunculated colorectal neoplasms at a Japanese tertiary cancer center between January 2014 and December 2019. Baseline characteristics, treatment results, and long-term outcomes were analyzed using 1:1 propensity score matching.

RESULTS

Seven hundred nine lesions were evaluated. The Tip-in EMR group included 1 lesion with a nonlifting sign but no lesions with fold convergence. After propensity score matching, each group included 140 lesions. The ESD group showed significantly higher en-bloc resection rates (99.3% vs 85.0%) and R0 resection rates (90.7% vs 62.9%). Procedure time was significantly shorter in the Tip-in EMR group (8 minutes vs 60 minutes). The Tip-in EMR and ESD groups did not differ significantly with respect to local recurrence rate (2.1% vs 0%).

CONCLUSIONS

Tip-in EMR is comparable with ESD with respect to the local recurrence rate but has a shorter procedure time, despite the lower en-bloc and R0 resection rates for 20- to 30-mm nonpedunculated colorectal neoplasms without fold convergence or nonlifting sign. Thus, Tip-in EMR could be a feasible alternative to ESD in these lesions.

Simulation training of laparoscopic pancreaticojejunostomy and stepwise training program on a 3D-printed model

AIM

Laparoscopic pancreaticojejunostomy is among the most difficult and high-risk operations. Surgeons with low or moderate seniority rarely are allowed to perform this surgery in clinics. Therefore, there is an urgent need to develop a reliable simulation training model focused on laparoscopic pancreaticojejunostomy and an effective stepwise training program.

METHODS

Surgeons with different working experiences or exposure to different training programs at Sir Run Run Shaw Hospital were divided into four groups. Each was required to perform laparoscopic pancreaticojejunostomy using a designed three-dimensional dry lab model. All surgeons' baseline characteristics and surgical performance, including operation time and score, were recorded and analysed. The authenticity of the model was evaluated by four senior surgeons.

RESULTS

The surgeon group with higher seniority had an older average age, longer working time, and had completed more laparoscopic cholecystectomy and laparoscopic common bile duct exploration procedures. Meanwhile, the surgeon group with higher seniority presented better operation performance, including shorter operation time and higher operation score in their initial simulation training. Resident surgeons who underwent stepwise training with the laparoscopic biliary-enteric anastomosis training program showed better initial performance than resident surgeons who underwent stepwise training with the laparoscopic basic suture training program. After repeated training, the surgeons showed improved surgical performance.

CONCLUSION

Our pancreaticojejunostomy model showed a good degree of discernibility, as surgeons with more experience performed better with the model for their initial simulation training in laparoscopic pancreaticojejunostomy. Stepwise training of the laparoscopic biliary-enteric anastomosis training program helped surgeons obtain a better initial performance, and repeated simulation training on this model improved the surgeon's operative performance.

Feasibility of endoscopic submucosal dissection for cecal tumors involving the ileocecal valve or appendiceal orifice

BACKGROUND AND AIM

Endoscopic resection of the ileocecal valve lesions (ICVL) and peri-appendiceal orifice lesions (PAOL), is challenging. This study aimed to evaluate the feasibility of endoscopic submucosal dissection (ESD) for ICVLs and PAOLs compared with other cecal lesions (OCEL).

METHODS

This was a multicenter, retrospective cohort study conducted at a cancer center hospital and two community hospitals. Non-pedunculated cecal lesions that were intended to be treated by ESD followed by at least one surveillance colonoscopy were included. The main outcome was curative resection defined as en-bloc resection and R0 resection without risk factors of metastases. The secondary outcome was co lon preservation.

RESULTS

A total of 206 patients with 206 cecal lesions, including 37 ICVL, 27 PAOL, and 142 OCEL, who were to be treated with ESD were included in this study. Curative resection rates were 75.7% for ICVL, 70.4% for PAOL, and 77.5% for OCEL (P = 0.67). In the multivariate analysis of predictors of curative resection, tumor size (<40 mm) (odds ratio [OR] 2.40; 95% confidence intervals [CI], 1.14-5.04; P = 0.02) and a negative non-lifting sign (OR 6.12; 95% CI, 2.55-14.60; P < 0.01) were significant. Colon preservation was achieved for 91.9% of the ICVL, 92.6% of the PAOL, and 90.8% of the OCEL (P = 0.947).

CONCLUSIONS

Based on curative resection and colon preservation rates, ESD was found to be feasible for ICVL and PAOL. Large tumor size (≥ 40 mm) and positive non-lifting signs were significant factors for non-curative resection.

The usefulness of a double-balloon endolumenal interventional platform for colorectal endoscopic submucosal dissection by non-expert endoscopists in a porcine model (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is an optimal treatment for colorectal tumors; however, it is technically difficult, especially for non-experts. Therefore, a device that helps non-experts perform colorectal ESD would be beneficial. A double-balloon endolumenal interventional platform (DEIP) was recently developed to assist colorectal ESD through endoscope stabilization and traction. This study assessed the usefulness of colorectal ESD using the DEIP (DEIP-ESD) by endoscopists, including non-experts, in a living porcine model.

METHODS

Two pigs were used to perform eight DEIP-ESD and eight conventional cap-assisted ESD (C-ESD) procedures. Three experts and five non-experts each resected one lesion using DEIP-ESD and one using C-ESD. We evaluated the treatment outcomes and performed stratified analyses between the experts and non-experts.

RESULTS

Dissection speed was significantly faster in DEIP-ESD than in C-ESD (13.3 mm²/min vs 28.5 mm²/min, P = 0.002). However, the total procedure time did not differ significantly between DEIP-ESD and C-ESD. In the stratified analyses, the dissection speed of non-experts was significantly faster in DEIP-ESD than in C-ESD (10.9 mm²/min vs 25.1 mm²/min, P = 0.016), while that of experts increased in DEIP-ESD but to a lesser extent (19.1 mm²/min vs 28.8 mm²/min, P = 0.1). The total procedure time did not differ between DEIP-ESD and C-ESD for both experts and non-experts. The self-completion rate of non-experts also increased in DEIP-ESD. Moreover, the number of muscularis propria injuries induced by non-experts was fewer in DEIP-ESD than in C-ESD.

CONCLUSIONS

DEIP could facilitate colorectal ESD by improving dissection efficiency without increasing adverse events, especially when performed by non-experts.

Diving, lifting, and horizontal dissection followed by loop-clip traction (DLH+T) can facilitate mucosal flap creation during colorectal ESD

BACKGROUND

Colorectal ESD is difficult because of the poor maneuverability and difficulty of mucosal flap creation. Diving, Lifting and Horizontal (DLH) dissection technique and loop-clip traction are two different methods to facilitate mucosal trimming and adequate mucosal flap creation. We combined the advantages of these two techniques (DLH+T) in our daily practice colorectal ESD since July 2020.

OBJECTIVE

The purpose of this study was to examine the outcomes of DLH+T dissection compared with the conventional dissection.

METHODS

We retrospectively reviewed the clinical using DLH+T dissection compared with the conventional dissection since January 2018 at a single tertiary care institution. Postoperative short-term outcomes were investigated after the procedure including mucosal flap creation time, dissection time, dissection speed, en bloc resection rate, and perioperative complications.

RESULTS

28 lesions were in DLH+T dissection group and 39 lesions in the conventional dissection group. The outcomes including en bloc resection rate, dissection speed, and complication between the two groups were similar. The mean mucosal flap creation time (p = 0.035) and the mean dissection speed (p = 0.041) of the DLH+T dissection group was significantly shorter and faster.

CONCLUSION

DLH dissection followed by loop-clip traction (DLH+T) technique is a useful technique for safe, efficient, and adequate mucosal flap creation, which can increase the dissection speed and may prevent complication, especially in biopsy-related submucosal fibrosis.

Efficacy of the pocket-creation method with a traction device in endoscopic submucosal dissection for residual or recurrent colorectal lesions

Background/Aims

Endoscopic submucosal dissection (ESD) for residual or recurrent colorectal lesions after incomplete resection is challenging because of severe fibrosis. This study aimed to compare the efficacy of the pocket-creation method (PCM) with a traction device (TD) with that of conventional ESD for residual or recurrent colorectal lesions.

Methods

We retrospectively studied 72 patients with residual or recurrent colorectal lesions resected using ESD. Overall, 31 and 41 lesions were resected using PCM with TD and conventional ESD methods, respectively. We compared patient background and treatment outcomes between the PCM with TD and conventional ESD groups, respectively. The primary endpoints were en bloc resection and R0 resection rates. The secondary endpoints were the dissection speed and incidence of adverse events.

Results

En bloc resection was feasible in all cases with PCM with TD, but failed in 22% of cases of conventional ESD. The R0 resection rates for PCM with TD and conventional ESD were 97% and 66%, respectively. Dissection was significantly faster in the PCM with TD group (13.0 vs. 7.9 mm²/min). Perforation and postoperative bleeding were observed in one patient in each group.

Conclusions

PCM with TD is an effective method for treating residual or recurrent colorectal lesions after incomplete resection.

Factors for conversion risk of colorectal endoscopic submucosal dissection: a multicenter study

BACKGROUND

Endoscopic submucosal dissection (ESD) has become a widely accepted treatment method for colorectal tumors; however, there are some persistent problems. This multi-center study aimed to characterize the risk factors for incomplete resection and perforation in standardized colorectal ESD procedures.

METHODS

This study included 2423 consecutive patients who underwent ESD for 2592 colorectal tumors between August 2013 and December 2018 at 11 institutions (1 academic hospital and 10 affiliated hospitals) from the Hiroshima GI Endoscopy Research Group. We evaluated the risk factors for interruption, piecemeal resection, and perforation of standardized colorectal ESD in relation to clinicopathologic and endoscopic characteristics.

RESULTS

The incidences of interruption, piecemeal resection, and perforation were 0.7%, 2.9%, and 3.0%, respectively. Multivariate analysis identified the following risk factors for interruption: perforation during the procedure, deep submucosal invasion (> 1000 μm), poor scope operability, and severe submucosal fibrosis. The risk factors for piecemeal resection included poor scope operability, severe submucosal fibrosis, and procedure time (≥ 85 min). The risk factors for perforation during the procedure were severe submucosal fibrosis, poor scope operability, procedure time (≥ 85 min), and tumor size (≥ 40 mm). Independent risk factors for severe submucosal fibrosis included a history of biopsy and lesions located on the fold or flexure.

CONCLUSIONS

Severe submucosal fibrosis and poor scope operability are the common risk factors for interruption, piecemeal resection, and perforation in standardized colorectal ESD.

Self-completion method of endoscopic submucosal dissection using the Endosaber for treating colorectal neoplasms (with video)

Endoscopic submucosal dissection (ESD) is effective for the treatment of colorectal neoplasms. We have developed a self-completion ESD (S-ESD) using Endosaber without requiring additional instruments or assistance. This prospective cohort study was conducted to investigate the feasibility of S-ESD for colorectal neoplasms. Patients with colorectal neoplasms measuring 20–40 mm in size were enrolled. A single operator, without assistance, performed ESD using only the Endosaber. The primary outcome was the success rate of S-ESD. Secondary outcomes included procedure time, the rates of en bloc, complete, and curative resection, and complication rates, including the incidence of perforation and delayed bleeding. In total, 15 patients with 15 lesions were enrolled. The median size of the resected lesions was 28 mm (interquartile range 25–29 mm). S-ESD success rate of 100% was achieved. The median procedure time was 44 min (29.5–53.5 min). We observed en bloc, complete, and curative resection rates of 100%, 93.3%, and 86.7%, respectively, and a complication rate of 6.7% (perforation: 0%, delayed bleeding: 6.7%). S-ESD for colorectal neoplasms was successfully performed with favorable treatment outcomes and low complication rates. S-ESD reduces the number of devices and extent of assistance, making S-ESD a simple and cost-effective procedure.

Efficacy of single-balloon overtube for endoscopic submucosal dissection in the proximal colon: A propensity score-matched analysis

OBJECTIVES

A single-balloon overtube (SBO) can improve poor scope operability during colonic endoscopic submucosal dissection (ESD). We aimed to evaluate the clinical usefulness of SBO for ESD in the proximal colon and the predictive factors for cases in which SBO is useful.

METHODS

A total of 88 tumors located in the proximal colon resected by balloon-assisted ESD (BA-ESD) using SBO and 461 tumors resected by conventional ESD (C-ESD) between June 2015 and November 2020 were considered. Seventy-eight tumors each in the BA-ESD and C-ESD groups were matched by propensity score matching. ESD outcomes were compared between the groups, and a decision tree analysis was performed to explore the predictive factors for cases in which SBO is useful.

RESULTS

There were no significant differences between the groups in the major outcomes such as en bloc resection rate (95% vs. 99%, p = 0.17), R0 resection rate (92% vs. 96%, p = 0.30), mean dissection speed (16 mm²/min vs. 16 mm²/min, p = 0.53), and intraoperative perforation rate (5% vs. 6%, p = 0.73). Even when considering cases with poor preoperative scope operability, there were no significant differences between the groups. Comparison of tumors ≥40 mm in diameter between the groups confirmed that the intraoperative perforation rate was significantly lower in the BA-ESD group than in the C-ESD group (0% vs. 24%, p = 0.0188).

CONCLUSION

SBO is useful for ESD of tumors ≥40 mm in diameter in the proximal colon to prevent intraoperative perforation, which usually has a long procedure time.

Endoscopic submucosal dissection for colorectal laterally spreading tumors: Clinical outcomes and predictors of technical difficulty

OBJECTIVE

We aimed to investigate the clinical outcomes of endoscopic submucosal dissection (ESD) for the treatment of colorectal laterally spreading tumors (LSTs) and the factors related to technical difficulty.

METHODS

Consecutive patients who underwent ESD for colorectal LSTs between June 2013 and January 2019 were retrospectively included. Factors associated with difficult ESD procedures (defined as conversion to piecemeal resection or discontinuation of endoscopic procedure), and dissection with a slow speed (<8 mm² /min), were determined using the logistic regression analysis.

RESULTS

A total of 325 patients with 342 colorectal LSTs (median size 20.0 mm) were enrolled. The proportions of granular (LST-G) and non-granular LST (LST-NG) were 62.9% and 37.1%, respectively. The overall en bloc and complete resection rates were 89.8% and 81.9%, respectively. The endoscopic procedure was discontinued in four lesions (1.2%), and 31 (9.1%) converted to piecemeal resection because of technical difficulty. Using multivariate analysis, positive non-lifting sign (odds ratio [OR] 19.9, P < 0.001), tumor size ≥20 mm (OR 10.0, P < 0.001), and less experienced endoscopists (OR 3.7, P = 0.005) were independent factors for technically difficult procedure. Positive non-lifting sign (OR 3.7, P = 0.004), lesion size <20 mm (OR 3.7, P < 0.001), LST-NG type (OR 1.8, P = 0.034), and less colorectal ESD experience (OR 1.9, P = 0.016) were independent factors of slow-speed dissection.

CONCLUSIONS

ESD was feasible and safe for treating colorectal LSTs. Positive non-lifting sign and tumor ≥20 mm indicated difficult ESD procedures. Technical failure was more likely to occur in lesions resected by less-experienced endoscopists. Dissection speed might be improved with more experienced operators.

Endoscopic submucosal dissection in tumors extending to the dentate line compared to proximal rectal tumors: a systematic review with meta-analysis

Endoscopic submucosal dissection (ESD) is a validated treatment for early rectal tumors, but whether this therapy is efficient or not for rectal tumors extending to the dentate line (RTDL) remains unclear. We performed a systematic review and meta-analysis to assess the effectiveness and safety of ESD in RTDL compared to non-RTDL. A search in PubMed, Scopus and the Cochrane library up to April 2020 was conducted to identify studies that compared ESD in both localizations (RTDL and non-RTDL), reporting at least one main outcome (en bloc, complete resection, recurrence). Secondary outcomes were adverse event occurrence. Five observational studies including 739 patients with a total of 201 RTDL and 538 non-RTDL were considered. The proportion of female sex (66% vs. 36.9%, P < 0.001) and tumor size [mean difference = 7.75, 95% confidence interval (CI): 3.01-12.49, P = 0.001] were higher in the RTDL group. There were no differences in en bloc resection rates between RTDL and non-RTDL groups [odds ratio (OR): 0.95, 95% CI: 0.50-1.79, P = 0.087]. The complete resection rate was significantly higher in the non-RTDL group (OR: 1.72, 95% CI: 1.18-2.53, P = 0.005, I2 = 0%). However, recurrence rates were comparable (RD: -0.04, 95% CI: -0.07 to 0.00, P = 0.06, I2 = 0%). Concerning adverse events, there were no differences in terms of perforation (OR: 0.9, 95% CI: 0.26-3.08, P = 0.86, I2 = 0%) or delayed bleeding (OR: 0.64, 95% CI: 0.17-2.42, P = 0.51, I2 = 35%). Anal pain rate was 28% (95% CI: 21.4-35.8%). ESD is an effective and safe therapeutic approach for RTDL with comparable recurrence rate to non-RTDL. The lower complete resection rate in RTDL needs to be clarified in studies.

The feasibility of endoscopic submucosal dissection for colorectal lesions larger than 10 cm

BACKGROUND

Although endoscopic submucosal dissection (ESD) enables en bloc removal of colorectal neoplasms, its effectiveness for larger lesions (≥ 10 cm in diameter) is undetermined. We aimed to investigate the feasibility and safety of ESD for colorectal lesions ≥ 10 cm wide.

METHODS

This retrospective study included 3591 consecutive colorectal lesions managed with ESD from June 2012 through December 2020. Clinicopathological characteristics and treatment outcomes were compared between lesions ≥ 10 cm wide and lesions 5-10 cm wide.

RESULTS

There were 50 patients in the ≥ 10 cm group and 270 patients in the 5-10 cm group. Among patients in the ≥ 10 cm group, lesions were most often in the rectum (50.0%), and the laterally spreading tumor-granular nodular mixed type (LST-G-M) was most prevalent (41/50, 82%). Although patients in the ≥ 10 cm group a longer mean ESD procedure time (186.0 vs. 94.4 min, p < 0.001), the dissection speed was significantly higher in this group (0.50 vs. 0.41 cm²/min, p = 0.003). The en bloc and curative resection rates were comparable between the ≥ 10 cm and 5-10 cm groups (100% vs. 99.6% and 86.0% vs. 88.5%, respectively). Although the stenosis rate was higher in the ≥ 10 cm group (4% vs. 0%), the delayed bleeding and perforation rates were similar between the two groups.

CONCLUSIONS

ESD for colorectal lesions ≥ 10 cm wide is feasible and curative, even though it is associated with higher technical difficulty and longer procedure times compared with ESD for smaller lesions (Number: UMIN 000044313).

Construction of a novel predictive nomogram for difficult procedure of endoscopic submucosal dissection for colorectal neoplasms

OBJECTIVES

To determine the predictors of difficult colorectal endoscopic submucosal dissection (ESD) and to develop a preoperative predictive model for difficult colorectal ESD procedures.

METHODS

Colorectal neoplasms intended to be resected by ESD in our center between August 2013 and February 2019 were retrospectively enrolled. An ESD procedure which took more than 30 min, failed to remove the lesions en bloc or converted to surgery was defined as difficulty. Logistic regression analysis was conducted to find out the predictors of difficult ESD. A nomogram integrating independent predictors was developed and validated with respect to its discrimination, calibration and clinical application, using the receiver operating characteristic (ROC) curve, calibration plot and decision curve analysis (DCA), respectively.

RESULTS

A total of 368 colorectal neoplasms in 355 patients were included. The independent predictors for difficult colorectal ESD were size ≥2 cm (odds ratio [OR] = 6.102, p < .001), positive non-lifting sign (OR = 6.569, p = .005), lesions located in left colon (OR = 2.475, p = .036) or rectum (OR = 2.183, p = .048), laterally spreading tumors (LSTs) (OR = 2.501, p = .008) and less colorectal ESD experience (≤20 cases) (OR = 2.3091, p = .028). The nomogram model incorporating the above predictors performed well in both of the training and validation sets (area under the cure [AUC] = 0.786 and 0.784, respectively). DCA demonstrated the clinical benefit of the nomogram was superior to that of each independent predictor alone.

CONCLUSIONS

The nomogram incorporating tumor size, location, morphology, non-lifting sign and ESD experience of operator can be conveniently used to facilitate the preoperative prediction of difficult colorectal ESD.

Hybrid endoscopic mucosal resection and full-thickness resection for large colonic polyps harboring a small focus of invasive cancer: a case series

Endoscopic treatment of large laterally spreading tumors (LSTs) with a focus of submucosally invasive colorectal cancer (T1 CRC) can be challenging. We evaluated outcomes of a hybrid resection technique using piecemeal endoscopic mucosal resection (pEMR) and endoscopic full-thickness resection (eFTR) in patients with large colonic LSTs containing suspected T1 CRC. Six hybrid pEMR-eFTR procedures for T1 CRCs were registered in a nationwide eFTR registry between July 2015 and December 2019. In all cases, the invasive part of the lesion was successfully isolated with eFTR; with eFTR, histologically complete resection of the invasive part was achieved in 5 /6 patients (83.3 %). No adverse events occurred during or after the procedure. The median follow-up time was 10 months (range 6-27), with all patients having undergone ≥ 1 surveillance colonoscopy. One patient had a small adenomatous recurrence, which was removed endoscopically. In conclusion, hybrid pEMR-eFTR is a promising noninvasive treatment modality that seems feasible for a selected group of patients with large LSTs containing a small focus of T1 CRC.

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.

The impact of submucosal fatty tissue during colon endoscopic submucosal dissection in a western center

OBJECTIVES

Obesity is associated with submucosal fatty tissue. The main aim of this study was to assess the impact of submucosal fatty tissue on the success of colonic endoscopic submucosal dissection (C-ESD) in a western population.

METHODS

This was a retrospective analysis of 125 consecutive C-ESDs performed between October 2015 and July 2017. Fatty tissue sign was defined as positive when the submucosal layer was covered with fatty tissue. The complexity of performing an ESD was assessed by the performing endoscopist, defined by the occurrence of intraprocedural perforation, inability to complete an en-bloc resection or a procedure time exceeding 180 min.

RESULTS

Fatty tissue sign positive was present in 44.8% of the procedures. There were 28 (22.4%) c-ESD defined as complex. Factors associated with complex ESD included; fatty tissue sign [odds ratio (OR) 12.5; 95% confidence interval (CI), 1.9-81.9; P = 0.008], severe fibrosis (OR 148.6; 95% CI, 6.6-3358.0; P = 0.002), poor maneuverability (OR 267.4; 95% CI, 11.5-6212.5; P < 0.001) and polyp size ≥35 mm (OR 17.2; 95% CI, 2.6-113.8; P = 0.003). In patients demonstrating the fatty tissue sign, BMI and waist-to-height ratio (WHtR) were higher (27.8 vs. 24.7; P < 0.001 and 0.56 vs. 0.49; P < 0.001, respectively) and en-bloc resection was achieved less frequently (76.8 vs. 97.1%, P = 0.001). Multivariate analysis revealed higher risk of fatty tissue sign positive associated with WHtR ≥0.52 (OR 26.10, 95% CI, 7.63-89.35, P < 0.001).

CONCLUSION

This study demonstrates that the fatty tissue sign contributes to procedural complexity during C-ESD. Central obesity correlates with the likelihood of submucosal fatty tissue and as such should be taken into account when planning procedures.

Prediction of technically difficult endoscopic submucosal dissection for large superficial colorectal tumors: a novel clinical score model

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is a promising technique for removing superficial GI tumors, but ESD is technically difficult. The aim of this study was to establish a clinical score model for grading technically difficult colorectal ESD.

METHODS

Data on patients, lesions, and outcomes of colorectal ESD at 2 centers were analyzed. The objective parameter of successful ESD within 60 minutes was set as an endpoint to evaluate the difficulty. Independent predictors of difficulty in the derivation cohort were identified by multiple logistic regression analysis and used to develop a clinical score. We validated the score model in the validation cohort.

RESULTS

The clinical score comprised tumor size of 30 to 50 mm (1 point) or ≥50 mm (2 points), at least two-thirds circumference of the lesion (2 points), location in the cecum (1 point), flexure (2 points) or dentate line (1 point), and laterally spreading tumor nongranular lesions (1 point). Areas under the receiver operator characteristic curves for the score model were comparable (derivation [.70] vs internal validation [.69] vs external validation [.69]). The probability of successful ESD within 60 minutes in easy (score = 0), intermediate (score = 1), difficult (score = 2-3), and very difficult (score ≥4) categories were 75.0%, 51.3%, 35.6%, and 3.4% in the derivation cohort; 73.3%, 47.9%, 31.8%, and 16.7% in the internal validation cohort; and 79.5%, 66.7%, 43.3%, and 20.0% in the external validation cohort, respectively.

CONCLUSIONS

This clinical score model accurately predicts the probability of successful ESD within 60 minutes and can be applied to grade the technical difficulty before the procedure.

Tip-in Endoscopic Mucosal Resection for 15- to 25-mm Colorectal Adenomas: A Single-Center, Randomized Controlled Trial (STAR Trial)

INTRODUCTION

One-piece endoscopic mucosal resection (EMR) for lesions >15 mm is still unsatisfactory, and attempted 1-piece EMR for lesions >25 mm can increase perforation risk. Therefore, modifications to ensure 1-piece EMR of 15- to 25-mm lesions would be beneficial. The aim of this study was to investigate whether Tip-in EMR, which anchors the snare tip within the submucosal layer, increases en bloc resection for 15- to 25-mm colorectal lesions compared with EMR.

METHODS

In this prospective randomized controlled trial, patients with nonpolypoid colorectal neoplasms of 15-25 mm in size were recruited and randomly assigned in a 1:1 ratio to undergo Tip-in EMR or standard EMR, stratified by age, sex, tumor size category, and tumor location. The primary endpoint was the odds ratio of en bloc resection adjusted by location and size category. Adverse events and procedure time were also evaluated.

RESULTS

We analyzed 41 lesions in the Tip-in EMR group and 41 lesions in the EMR group. En bloc resection was achieved in 37 (90.2%) patients undergoing Tip-in EMR and 30 (73.1%) who had EMR. The adjusted odds ratio of en bloc resection in Tip-in EMR vs EMR was 3.46 (95% confidence interval: 1.06-13.6, P = 0.040). The Tip-in EMR and EMR groups did not differ significantly in adverse event rates (0% vs 4.8%) or median procedure times (7 vs 5 minutes).

DISCUSSION

In this single-center randomized controlled trial, we found that Tip-in EMR significantly improved the en bloc resection rate for nonpolypoid lesions 15-25 mm in size, with no increase in adverse events or procedure time.

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.

Current Status and Prospects of Endoscopic Resection Technique for Colorectal Tumors

Currently, endoscopic submucosal dissection (ESD) is a well-established and common treatment for intramucosal colorectal cancer in Japan. However, colorectal ESD is technically more difficult to perform than esophageal and gastric ESD, and some lesions, such as fibrotic lesions, are difficult to dissect by endoscopy. Several techniques, such as the pocket-creation method and laparoscopically assisted endoscopic polypectomy, have been utilized for challenging targets. In recent years, endoscopic full-thickness resection (EFTR) using full-thickness resection devices have mainly been performed in Western countries. We have used laparoscopy and endoscopy cooperative surgery for colorectal tumors (LECS-CR) since 2011 for the challenging treatment of colorectal ESD. Improvements in ESD techniques have resulted in an increase in the literature on EFTR, and LECS-CR may be considered an effective endoscopic technique for colorectal ESD in the future.

Snare Tip Is an Alternative Tool for Colorectal Endoscopic Submucosal Dissection

BACKGROUND

Colorectal endoscopic submucosal dissection is typically performed by specialized knife, such as a dual knife. However, it is not covered by Taiwan's National Health Insurance. In the literature review, using a traditional snare tip for endoscopic submucosal dissection has been reported for stomach lesions only.

OBJECTIVE

The purpose of this study was to evaluate the outcomes of colorectal endoscopic submucosal dissection using a snare tip.

DESIGN

We retrospectively reviewed the clinical using of a snare tip compared with a dual knife for colorectal endoscopic submucosal dissection. Postoperative short- and long-term outcomes were investigated after the procedure.

SETTINGS

This study was conducted at a single tertiary care institution.

PATIENTS

Patients who could not afford the expense of a specialized knife were included.

MAIN OUTCOME MEASURES

Dissection time, dissection speed, and perioperative complications were used for short-term outcome measurement. Recurrence-free rate was used for long-term outcome measurement.

RESULTS

Twenty-one lesions were in the snare tip group and 57 lesions in the dual knife group. The outcomes, including rate of en bloc resection, complication, local recurrence, and recurrence-free interval, between the 2 groups were similar. The mean resected specimen diameter in the dual knife group is larger than the snare tip group (p = 0.041). The dissection time of the snare tip group was shorter than the dual knife group (p = 0.025). However, the dissection speed was significantly slower in the snare tip group than in the dual knife group (p = 0.008).

LIMITATIONS

This study was a retrospective and single doctor chart review in nature with a limited patient number.

CONCLUSIONS

The snare tip is an alternative tool for colorectal endoscopic submucosal dissection in a selected population without the support of specialized knives, such as the dual knife. Although the dissection speed is slower using a snare tip, it is still a recommended technique for developing country or low-income patients.

Factors influencing interruption of colorectal endoscopic submucosal dissection

BACKGROUND AND AIMS

Although colorectal endoscopic submucosal dissection (ESD) has become a standardized procedure worldwide, the difficulty of the procedure is well known. However, there have been no studies assessing the causes of treatment interruption. The present study aimed to evaluate the factors involved in the interruption of colorectal ESD.

METHODS

We retrospectively analyzed 1116 consecutive superficial colorectal neoplasms of 1012 patients who were treated with ESD between August 2008 and September 2018. The clinicopathological characteristics and treatment outcomes were analyzed.

RESULTS

Interrupted ESD was reported in 14 lesions (1.3%) of the total study population. Univariate analysis of clinical characteristics indicated that age, 0-I macroscopic-type tumor, and tumor location on the left side colon were risk factors for interruption. Multivariate analysis revealed that 0-I macroscopic-type tumor was the sole preoperative independent risk factor for interruption. Univariate analysis revealed that the presence of muscle-retracting sign (MRS), deep submucosal tumor invasion, and intermediate invasive growth pattern represented the etiology of interruption. Multivariate analysis indicated that MRS can be a sole key sign for the interruption. Additionally, the resectability and curability of 0-I type tumors were significantly inferior to those of predominantly lateral spreading tumors. Observations of 0-I macroscopic-type tumors, MRS, and submucosal deep invasion were significantly more frequent in interrupted cases. Conventional endoscopic images without magnification endoscopy were more associated with interruption than irregular surfaces or Vi pit patterns in cases with 0-I type tumors.

CONCLUSION

ESD of 0-I type tumors is highly disruptive, and undiagnosable submucosal infiltration can reduce the curability.

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.

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.

Efficacy of preemptive endoscopic submucosal dissection and surgery for synchronous colorectal neoplasms

BACKGROUND AND AIM

If patients with surgically resectable colorectal cancershave synchronous colorectal neoplasms that are difficult to remove by endoscopic mucosal resection, preemptive endoscopic submucosal dissection (ESD) can avoid excessive colorectal resection. The aim of this study was to evaluate the efficacy of the strategy of preemptive ESD and surgery for synchronous colorectal neoplasms.

METHODS

Patients who underwent preemptive ESD and surgery for synchronous colorectal neoplasms between September 2002 and December 2017 were enrolled in this retrospective cohort study. The proportion of cases in which extended surgery could be avoided following curative ESD was calculated. Clinicopathological characteristics were evaluated for all patients and long-term outcomes were analyzed for patients who underwent curative ESD and surgery.

RESULTS

A total of 45 consecutive patients with 47 endoscopically-resected lesions and 46 surgically-resected lesions were retrospectively evaluated. Curative ESD was achieved in 44 lesions (93.6%) and an extended surgical procedure could be avoided in 42 patients (93.3%). Intraoperative perforation occurred in two lesions (4.3%), delayed perforation in one lesion (2.1%), and delayed bleeding in two lesions (4.3%). Final stages were as follows: stage 0, 3 patients (7.1%); stage I, 23 patients (54.8%); stage II, 3 patients (7.1%); stage III, 12 patients (28.6%); and stage IV, 1 patient (2.4%). The 5-year overall survival rates of patients with all pathological stages, stage 0-II, and stage III-IV were 93.7%, 100%, and 79.1%, respectively.

CONCLUSION

The strategy of preemptive ESD and surgery for synchronous colorectal neoplasms is minimally invasive and has a favorable prognosis.

The pocket-creation method may facilitate endoscopic submucosal dissection of large colorectal sessile tumors

Background and study aims  Resecting large colorectal sessile tumors using endoscopic submucosal dissection (ESD) is challenging because of severe submucosal fibrosis. Previously, we reported that ESD strategy using the pocket-creation method (PCM) is useful for large colorectal sessile tumors, but there are no large studies reporting the effectiveness and safety of the PCM for resection of large colorectal sessile tumors. Patients and methods  This was a retrospective review of 90 large colorectal sessile tumors in 89 patients who underwent ESD in our institution. Large colorectal sessile tumors were defined as polypoid lesions 20 mm or more in diameter. We divided them into PCM (n = 40) and conventional method (CM) groups (n = 50). The primary outcome measure was en bloc resection. The inverse-probability-treatment weighting (IPTW) approach was used to adjust for selection bias. Results  Both PCM and CM achieved high en bloc resection (100 % vs. 94 %, non-adjusted P  = 0.25, IPTW-adjusted P  = 0.19) and R0 resection rates (88 % vs. 78 %, non-adjusted P  = 0.28, IPTW-adjusted P  = 0.27). When PCM was used, the rate of pathologically negative vertical margins was significantly greater than with the CM (IPTW-adjusted P  = 0.045). The dissection time was significantly shorter (IPTW-adjusted P  = 0.025) and dissection speed faster (IPTW-adjusted P  = 0.013) using the PCM than when the CM was used. There was no significant difference in the incidence of adverse events (intraprocedural perforation and delayed bleeding, IPTW-adjusted P  = 0.68). Conclusion  Although en bloc resection and R0 resection rates were similar, PCM significantly increased the rate of negative vertical margins with rapid dissection for treatment of large colorectal sessile tumors.

Predictive factors for difficult endoscopic submucosal dissection for esophageal neoplasia including failure of en bloc resection or perforation

BACKGROUND

Endoscopic submucosal dissection (ESD) is accepted as the standard treatment for early-stage esophageal neoplasia. However, esophageal perforation may occur, leading to mediastinitis and pneumothorax, which occasionally require emergency surgery. Moreover, failure of en bloc resection causes local recurrence. However, studies on the predictors of such difficulties during ESD are limited. Hence, we evaluated the predictors associated with the difficulty of ESD for esophageal neoplasia including failure of en bloc resection or perforation.

METHODS

Data of 549 consecutive patients who were treated with ESD between May 2004 and March 2016 at a single institution were retrospectively studied. Exclusion criteria were the presence of metachronous esophageal neoplasia or missing data. The primary outcome was determining the predictors associated with the difficulty of ESD for esophageal neoplasia including failure of en bloc resection or perforation.

RESULTS

Altogether, 543 patients with 736 lesions were evaluated. Failure of en bloc resection occurred in 6 patients (1.1%) with 6 lesions, and perforation occurred in 11 patients (2.0%) with 11 lesions (1.5%). Multivariate logistic regression analysis showed that large lesion diameter (odds ratio [OR] 1.49; 95% confidence interval [CI] 1.21-1.84; p < 0.001) and previous chemoradiotherapy (OR 5.24; 95% CI 1.52-18.06; p = 0.009) were independent predictive factors.

CONCLUSIONS

Larger lesions and previous chemoradiotherapy for esophageal cancer increased the risk for failure of en bloc resection or perforation in patients who underwent esophageal ESD.

Clinical utility of the pocket-creation method with a traction device for colorectal endoscopic submucosal dissection

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) is technically demanding while ensuring safety, especially in cases with fibrosis and/or poor maneuverability. To overcome such difficulties, we developed a novel method called the pocket-creation method with a traction device (PCM with TD). We then evaluated the effectiveness and safety of PCM with TD in colorectal ESD compared to other conventional methods.

METHODS

In total, 324 colorectal lesions treated with ESD from July 2018 to June 2019 were included. The following three treatment strategies were used: conventional ESD (CE), CE with TD, and PCM with TD. Patient backgrounds and treatment outcomes were retrospectively compared and analyzed.

RESULTS

As ESD methods, CE, CE with TD, and PCM with TD account for 58% (187/324), 24% (78/324), and 18% (59/324), respectively. No significant difference was observed among the three groups in en bloc and R0 resection rates or adverse events. The rate of lesions with fibrosis and poor maneuverability was significantly higher in the PCM with TD group (CE group vs CE with TD group vs PCM with TD group: fibrosis, 24% vs 47% vs 64%, p < 0.001; poor maneuverability, 5.3% vs 13% vs 20%, p = 0.002). Dissection speed was significantly higher in the PCM with TD than in the CE with TD group (p = 0.003).

CONCLUSIONS

PCM with TD can achieve a stable en bloc resection rate and R0 dissection rate without adverse events even in the hands of trainees, irrespective of the size and location of the lesion, presence of fibrosis, and under poor maneuverability conditions.

Efficacy and suitable indication of colorectal endoscopic submucosal dissection using a balloon-assisted endoscope

Background and Aim

Cases of colorectal endoscopic submucosal dissection (ESD) with poor maneuverability are often encountered. We aimed to evaluate the efficacy of balloon‐assisted endoscopy (BAE) for such cases.

Methods

We confirmed maneuverability preoperatively in 400 consecutive cases of colorectal ESD performed at a single center from April 2011 to April 2018. A total of 83 deep colon cases judged as having poor maneuverability were retrospectively reviewed; 54 cases underwent BAE with a single balloon endoscope (group B), and 29 cases underwent conventional procedures without BAE (group C). Tumor size, procedure duration, dissection speed, en bloc resection rate, histology, and associated complications were compared between groups.

Results

The mean tumor size, tumor invasiveness, fibrosis, and complications did not differ between groups. Although the en bloc resection rate did not differ (both 98%), the groups significantly differed with regard to the R0 resection rate (B: 96%; C: 83%; P = 0.048). Overall, the procedure duration (B: 51 min; C: 70 min; P = 0.17) and dissection speed (B: 19.4 mm²/min; C: 17.4 mm²/min; P = 0.13) were not significantly different between groups. However, the dissection speed for lesions in the cecum/ascending colon was significantly faster in group B than in group C (B: 22.3 mm²/min; C: 11.3 mm²/min; P = 0.037).

Conclusions

In cases of colorectal ESD with poor maneuverability, the use of BAE contributed to an improvement in the R0 resection rate. In addition, BAE contributed to a quicker dissection speed for lesions located in the cecum/ascending colon.

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.

Predictive Factors of Mild and Severe Fibrosis in Colorectal Endoscopic Submucosal Dissection

BACKGROUND AND STUDY AIMS

Varying degrees of fibrosis in colorectal endoscopic submucosal dissection (ESD) make the procedure difficult. Consensus on the predictive factors of fibrosis degree (mild or severe) has not been established. We conducted a study to identify the predictive factors and to examine the feasibility of ESD for fibrotic lesions.

PATIENTS AND METHODS

We included 518 patients who had undergone ESD for 558 lesions from April 2012-September 2018. Patients were classified into fibrosis or no-fibrosis groups, and logistic regression analysis was performed to identify predictive factors of fibrosis. Subgroup analyses were performed for fibrosis degree.

RESULTS

The total incidence of fibrosis was 21.1% (mild: 14.1%; severe: 7.1%). Although the curative resection rate (free margin: invasion depth less than 1000 μm: no lymphatic invasion, vascular involvement) was lower in the fibrosis group compared with the control (80.7% vs. 97.6%), neither the en bloc resection rate (99.1% vs. 100%) nor incidence of perforation (0.9% vs. 0.2%) differed between the two groups. Multivariate analysis revealed that a cecal location, preoperative biopsy, straddling fold, laterally spreading tumor-non-granular-pseudo-depressed (LST-NG-PD) type were predictive of mild fibrosis. The presence of a straddling fold and a protruded lesion were independent predictive factors of severe fibrosis.

CONCLUSIONS

We identified the predictive factors of mild and severe fibrosis. It is preferable that a more experienced physician performs ESD for the lesions with F2 fibrosis.