Factors affecting the technical difficulty and clinical outcome of endoscopic submucosal dissection for colorectal tumors

Predictive Factors for Procedure Time for Closure of Mucosal Defect Following Colorectal Endoscopic Submucosal Dissection

Goals

The present study was conducted to clarify predictive factors related to procedure time for closure of a mucosal defect following colorectal endoscopic submucosal dissection.

Background

To prevent complications following a colorectal endoscopic submucosal dissection (ESD) procedure, closure of the resultant mucosal defect is considered to be most effective. However, closure after colorectal ESD is challenging, and technical difficulties can lead to a longer procedure time. Although it is important to clarify predictive factors related to the time needed for effective treatment planning, no such validated data obtained prior to the present study have been reported.

Study

Overall, 61 consecutive patients who underwent colorectal ESD for a colorectal neoplasm sized greater than 20 mm were enrolled. Immediately after performing colorectal ESD, closure of the mucosal defect was implemented using a loop clip closure method. Factors with influence on closure procedure time were evaluated using multiple linear regression analyses.

Results

Results obtained with a multiple linear regression model demonstrated that resected specimen size (β = 0.690, p < 0.01) and colon site (β = -0.209, p = 0.027) were factors with influence on the closure procedure. Those results were considered relevant to explain the 50.5% variance in time until completion of closure; thus, goodness of fit was considered to be high.

Conclusions

Findings obtained in this study were helpful to clarify predictive factors with influence on procedure time. The fit of the model was good, thus allowing for closure performance based on outcome prediction.

Comparison of traction vs. snare as rescue methods for challenging colorectal endoscopic submucosal dissection: Propensity score-matched study

Background and study aims

To address the challenges of difficult colorectal endoscopic submucosal dissection (ESD), conversion to snare resection (rescue-snare ESD: rSnare), a variant of hybrid ESD, is commonly proposed. However, rSnare is associated with a lower en bloc resection rate compared with conventional ESD. Traction-assisted ESD has emerged as a technique to facilitate dissection, but its effectiveness as a rescue method remains unclear. This study was the first to compare the effectiveness of rSnare and rescue-traction-assisted ESD (rTraction).

Patients and methods

This retrospective study involved 1464 consecutive lesions from 1372 patients with superficial colorectal neoplasms across eight institutions. Among these, 162 lesions required rescue methods of rSnare or rTraction. After propensity score matching, 88 lesions treated with either rSnare or rTraction were analyzed.

Results

The rTraction group exhibited significantly higher en bloc resection and R0 resection rates (93.2% and 77.3%, respectively) compared with the rSnare group (45.5% and 38.6%, respectively). However, average procedure time was significantly longer in the rTraction group (122.3 ± 72.5 min) compared with the rSnare group (92.2 ± 54.2 min). In the rTraction group, univariable and multivariable analyses identified traction initiation time > 75 minutes as the only independent predictor of procedure durations exceeding 120 minutes.

Conclusions

Utilizing a traction device as a rescue technique in difficult colorectal ESD resulted in higher en bloc and R0 resection rates compared with conversion to snare resection. Initiating traction within 75 minutes may contribute to reducing overall procedure time for challenging colorectal ESD cases.

Prevalence of Endoscopically Curable Low-Risk Cancer Among Large (≥20 mm) Nonpedunculated Polyps in the Right Colon

BACKGROUND AND AIMS

Endoscopic submucosal dissection is increasingly promoted for the treatment of all large nonpedunculated colorectal polyps (LNPCPs) to cure potential low-risk cancers (superficial submucosal invasion without additional high-risk histopathologic features). The effect of a universal en bloc strategy on oncologic outcomes for the treatment of LNPCPs in the right colon is unknown. We evaluated this in a large Western population.

METHODS

A prospective cohort of patients referred for endoscopic resection (ER) of LNPCPs was analyzed. Patients found to have cancer after ER and those referred directly to surgery were included. The primary outcome was to determine the proportion of right colon LNPCPs with low-risk cancer.

RESULTS

Over 180 months until June 2023, 3294 sporadic right colon LNPCPs in 2956 patients were referred for ER at 7 sites (median size 30 [interquartile range 22.5-37.5] mm). A total of 63 (2.1%) patients were referred directly to surgery, and cancer was proven in 56 (88.9%). A total of 2851 (96.4%) of 2956 LNPCPs underwent ER (median size 35 [interquartile range 25-45] mm), of which 75 (2.6%) were cancers. The overall prevalence of cancer in the right colon was 4.4% (n = 131 of 2956). Detailed histopathologic analysis was possible in 115 (88%) of 131 cancers (71 after ER, 44 direct to surgery). After excluding missing histopathologic data, 23 (0.78%) of 2940 sporadic right colon LNPCPs were low-risk cancers.

CONCLUSIONS

The proportion of right colon LNPCPs referred for ER containing low-risk cancer amenable to endoscopic cure was <1%, in a large, multicenter Western cohort. A universal endoscopic submucosal dissection strategy for the management of right colon LNPCPs is unlikely to yield improved patient outcomes given the minimal impact on oncologic outcomes.

CLINICALTRIALS

gov, Numbers: NCT01368289, NCT02000141.

Endoscopic submucosal dissection for proximal colonic lesions: An effective therapeutic option

Background and study aims

Due to the greater risks of adverse events (AEs) and the lower rate of submucosal invasive cancer (SMIC), large proximal colonic polyps are frequently treated by piecemeal endoscopic mucosal resection (EMR) in the West. However, this implies the risk of surgery to radicalize non-curative endoscopic resection in case of early colorectal cancer (CRC). We evaluated procedure outcomes in patients undergoing ESD for proximal colonic lesions at risk of SMIC.

Patients and methods

All consecutive patients with lesions at risk of SMIC proximal to splenic flexure referred for ESD at a tertiary center were prospectively included from 2019 to 2021. En bloc, R0, and curative resection rates were primary outcomes, while length of hospitalization, AEs, need for surgery due to AEs, and recurrence rates were secondary outcomes.

Results

A total of 116 patients (mean age: 68.4±10.91 years; men: 69.8%) were included. En bloc, R0, and curative resection rates were 84.5%, 78.4%, and 72.4%, respectively. T1 adenocarcinoma was reported in 25% of lesions (29/116). Eleven patients (9.5%) underwent secondary surgery due to non-curative resections; residual disease was found in one patient. Most frequent AE was intra-procedural perforation (9.9%); no AE required surgery. Median follow-up was 36 months; three of 97 recurrences (3.1%) at 6 months and one of 85 recurrence (1.2%) at 36 months were reported, which were all endoscopically treated.

Conclusions

In expert hands, ESD is effective and safe for proximal colonic lesions at risk of SMIC for the favorable balance between risk of AEs and benefit of avoiding unnecessary surgery, even for early CRC.

Endoscopic submucosal dissection for superficial ultra-low rectal tumors: outcomes and predictive factors for procedure difficulty

BACKGROUND

Ultra-low rectal endoscopic submucosal dissection (ESD) presents technical challenges due to anatomical features. The objective of this research was to determine the risk factors linked to unsuccessful curative resections and to create a nomogram predictive model to assess the likelihood of encountering technical challenges.

METHODS

Patients with ultra-low rectal tumors received ESD form June 2017 to December 2022 were retrospectively enrolled. An ESD procedure exceeding 30 min was deemed difficult. A logistic regression analysis was performed to pinpoint important factors and predictors. The effectiveness of the nomogram, which incorporated the identified predictors, was evaluated by employing receiver operating characteristic (ROC) curves, calibration plots, and decision curve analysis (DCA).

RESULTS

A total of 300 patients with ultra-low rectal tumors were enrolled, with a curative resection rate of 82.0%. Multivariate logistic regression revealed that poor lifting sign (OR = 3.282, P = 0.026), non-granular type laterally spreading tumors (LST-NG, OR = 2.230, P = 0.042) and procedure time ≥ 60 min (OR = 6.976, P = 0.010) contributed to non-curative resection. Predictors for ESD difficulty included tumor diameter ≥ 30 mm (compared with < 30 mm, 30-50 mm, OR = 2.450, P = 0.044; ≥ 50 mm, OR = 5.047, P = 0.009), ≥ 1/2 circumference involvement (OR = 3.183, P = 0.038); dentate line invasion (OR = 3.881, P = 0.026) and less colorectal ESD experience (OR = 3.415, P = 0.032). The nomogram performed well in both train and validation sets (area under the curve (AUC) = 0.873 and 0.810, respectively). Calibration plots exhibited satisfactory agreement between predicted and observed outcomes, and DCA showed superior clinical benefit of the model than individual predictors.

CONCLUSIONS

Poor lifting sign, LST-NG and procedure time ≥ 60 min were associated with non-curative resection for ultra-low rectal ESD. By including factors such as tumor size, location, and the operator's experience with ESD, the nomogram can predict the complexity of the procedure before surgery.

Comparing underwater endoscopic submucosal dissection and conventional endoscopic submucosal dissection for large laterally spreading tumor: a randomized controlled trial (with video)

BACKGROUND AND AIMS

Colorectal endoscopic submucosal dissection (ESD) is challenging despite its usefulness. Underwater ESD (UESD) provides better traction and a clearer view of the submucosal layer than conventional ESD (CESD). This study compared the efficiency of UESD and CESD for large (20-50 mm) laterally spreading tumors (LSTs).

METHODS

Preplanned sample size was calculated from our previous experience. As a result, 28 patients were required for the UESD group and CESD group each. The primary outcome was total procedure time; the secondary outcome was dissection speed.

RESULTS

Fifty-six patients were enrolled, and a total of 28 patients were assigned to each group. The mean LST size was 31.6 mm and 31.3 mm in the UESD and CESD groups, respectively. Fibrosis was observed in 67.9% and 60.7% of patients in the UESD and CESD groups. Total procedure time (mean ± standard deviation) for the UESD group was significantly shorter than that for the CESD group (49.5 ± 20.3 minutes vs 75.7 ± 36.1 minutes; mean difference, -26.2 minutes; 95% confidence interval, -42.0 to -10.5 minutes). Dissection speed of the UESD group was significantly faster than that of the CESD group (21.9 ± 6.9 mm2/min vs 15.2 ± 7.3 mm2/min; mean difference, 6.7 mm2/min; 95% confidence interval, 2.8 to 10.4 mm2/min). There was no difference between groups in the R0 resection rate or en bloc resection rate. No perforations were observed in either group.

CONCLUSIONS

UESD was superior to CESD in total procedure time and dissection speed. UESD can be recommended as the preferred method for the resection of large LSTs.

Comparative Study on the Effectiveness, Safety, and Economic Costs of Endoscopic Submucosal Dissection for Colorectal Tumors Under Conscious Sedation and General Anesthesia

BACKGROUND

Endoscopic submucosal dissection (ESD) is a minimally invasive surgical procedure used for en bloc removal of colorectal tumors. Although colorectal ESD is ideally conducted under conscious sedation, it is often performed under general anesthesia because of its complexity and lengthy duration. Currently, there is limited research on colorectal ESD performed under conscious sedation. The purpose of this study was to evaluate the effectiveness, safety, and economic cost of colorectal ESD under conscious sedation compared to general anesthesia.

MATERIALS AND METHODS

Retrospective analysis of 301 patients who underwent ESD treatment for colorectal tumors at the Endoscopy Center of Peking University Cancer Hospital from January 2018 to November 2020. Patients were divided into the sedation group (group S, n=88) and the general anesthesia group (group A, n=213) based on the anesthetic method. To balance the confounding factors between the 2 groups, 75 matched pairs were obtained after using propensity score matching (PSM). Intraoperative and postoperative parameters were then compared between the matched groups.

RESULTS

After PSM, there was no statistically significant difference between group S and group A in terms of the surgical time, en bloc resection rate, and complete resection rate. There was also no statistically significant difference in the occurrence rates of bleeding, perforation, and post-ESD electrocoagulation syndrome (PEECS) between the 2 groups. However, the length of hospital stay was significantly shorter in group S (1.23±0.89d) than in group A (5.92±3.05d) ( P <0.05). The hospitalization costs were also significantly lower in group S (16482.34±13154.32 yuan) compared with group A (34743.74±13779.40 yuan) (P < 0.05 ).

CONCLUSIONS

Compared to general anesthesia, performing ESD for colorectal tumors under conscious sedation has equivalent effectiveness and safety while shortening the hospital stay and reducing the economic costs.

The Derivation and External Validation of a Fibrosis Risk Model for Colorectal Tumours Undergoing Endoscopic Submucosal Dissection

Background: Endoscopic submucosal dissection (ESD) is an advanced technique that can become more challenging in the presence of submucosal fibrosis. Predicting the grade of fibrosis is important in order to identify technically difficult ESD. Aims and Methods: Our study aimed to derive and validate a prediction model to determine the preoperative degree of submucosal fibrosis in colorectal tumours undergoing ESD. A predictive model was developed to derive the probability of an increasing submucosal fibrosis in the derivation cohort and then externally validated. Results: 309 patients (age: 68 ± 10.9 years) underwent colorectal ESD between January 2016 and June 2020. F0, F1, and F2 fibroses were reported in 196 (63.4%), 70 (22.6%), and 43 (13.9%) cases, respectively. R0 resection was found in 266 (87%) lesions. At multivariable analysis in the derivation cohort, lesion morphology (OR = 0.37 and CI = 0.14-0.97 for LST-NG vs. 0-Is; OR = 0.29 and CI = 0.1-0.87 for the LST mixed type vs. 0-Is; and OR = 0.32 and CI = 0.1-1.03 for LST-G vs. 0-Is) and increasing size (OR = 1.02 and CI = 1.01-1.04 for a 1 mm increase) were significantly associated with an increasing degree of fibrosis. The model had fair discriminating ability in the derivation group (AUROC = 0.61 and CI = 0.52-0.69 for F1-F2 vs. F0 fibroses; AUROC = 0.61 and CI = 0.45-0.77 for F2 vs. F0-F1 fibroses) and in the validation group (AUROC = 0.71 and CI = 0.59-0.83 for F1-F2 vs. F0 fibroses; AUROC = 0.65 and CI = 0.52-0.77 for F2 vs. F0-F1 fibroses). Conclusions: Our findings introduce a new tool for the stratification of ESD technical difficulty based on lesion size and morphological characteristics which could become crucial during the procedure's planning process.

Risk factors for unsuccessful colorectal endoscopic submucosal dissection: A systematic review and meta-analysis

BACKGROUND AND AIMS

Despite its growing popularity, endoscopic submucosal dissection (ESD) for colorectal neoplasms is still technically challenging. The factors contributing to the failure of ESD are not yet comprehensively elucidated. Therefore, this systematic review was conducted to explore the potential risk factors associated with unsuccessful colorectal ESD.

METHODS

A comprehensive search of Medline and Embase databases was conducted to identify relevant publications from inception until March 14, 2023. Unsuccessful ESD was defined as cases involving incomplete resection or the occurrence of adverse events, such as perforation and delayed bleeding.

RESULTS

Among the 2067 citations initially identified, a total of 23 cohort studies and 16 case-control studies met the inclusion criteria. Following meta-analyses, several significant risk factors for incomplete resection were identified, including lesion diameter ≥40 or 50 mm, right-side colonic location, deeper submucosal invasion, and severe fibrosis. Similarly, lesion diameter ≥40 or 50 mm and severe fibrosis emerged as risk factors for perforation. However, no individual factor was found to be statistically associated with delayed bleeding.

CONCLUSIONS

This meta-analysis identified risk factors correlated with incomplete resection and adverse events following ESD. The findings provide valuable insights that can guide clinical decision-making, aiding gastroenterologists in accurately identifying high-risk individuals.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

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.

Diagnostic and therapeutic strategies for colorectal tumor with positive muscle-retracting sign

Objectives

Endoscopic submucosal dissection (ESD) for colorectal tumors with positive muscle-retracting (MR) sign often results in incomplete resection or discontinuation owing to the difficulty of submucosal dissection. The present study aimed to evaluate the usefulness of endoscopic ultrasonography (EUS) in diagnosing the MR sign and performing ESD using the pocket-creation method (PCM).

Methods

Thirty-six cases of colorectal tumors with positive MR sign during ESD between January 2015 and December 2021 were retrospectively reviewed. Cases were divided into two groups: 1) the conventional method (CM) group, comprising 29 cases, and 2) the PCM group with seven cases, in which preoperative EUS and ESD using PCM were performed. Treatment outcomes were compared between the groups. The diagnostic yield of EUS for the MR sign was evaluated among large sessile tumors >20 mm in which preoperative EUS was performed.

Results

Histologic diagnosis was adenoma or Tis carcinoma in 12 cases (33%), T1 carcinoma in 18 cases (50%), T2 carcinoma in four cases (11%), and unevaluable in two cases (6%). The sensitivity and specificity of the EUS-MR sign for large sessile tumors were 87.5% and 83.3%, respectively. ESD was achieved in all cases in the PCM group, although it was discontinued in eight cases (28%) in the CM group. There were significant differences between the PCM and CM groups in en bloc resection (100% vs. 48%, p = 0.013) and R0 resection rates (71% vs. 31%, p = 0.049).

Conclusion

The MR sign can be predicted by preoperative EUS, and ESD using PCM allows en bloc resection.

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.

Tumor size discrepancy between endoscopic and pathological evaluations in colorectal endoscopic submucosal dissection

BACKGROUND

Tumor size impacts the technical difficulty and histological curability of colorectal endoscopic submucosal dissection (ESD); however, the preoperative evaluation of tumor size is often different from histological assessment. Analyzing influential factors on failure to obtain an accurate tumor size evaluation could help prepare optimal conditions for safer and more reliable ESD.

AIM

To investigate the tumor size discrepancy between endoscopic and pathological evaluations and the influencing factors.

METHODS

This was a retrospective study conducted at a single institution. A total of 377 lesions removed by colorectal ESD at our hospital between April 2018 and March 2022 were collected. We first assessed the difference in size with an absolute percentage of the scaling discrepancy. Subsequently, we compared the clinicopathological characteristics of the correct scaling group (> -33% and < 33%) with that of the incorrect scaling group (< -33% or > 33%), which was further subdivided into the underscaling group (-33% or less of the discrepancy) and overscaling group (33% or more of the discrepancy), respectively. As secondary outcome measures, parameters on size estimation were compared between the underscaling and correct scaling groups, as well as between the overscaling and correct scaling groups. Finally, multivariate analysis was performed in terms of the following relevant parameters on size estimation: Pathological size, location, and possible influential factors (P < 0.1) in the univariate analysis.

RESULTS

The mean of absolute percentage in the scaling discordance was 21%, and 91 lesions were considered to be incorrectly estimated in size. The incorrect scaling was significantly remarkable in larger lesions (40 mm vs 28 mm; P < 0.001) and less experience (P < 0.001), and these two factors were influential on the underscaling (75 lesions; P < 0.001). Conversely, compared with the correct scaling group, 16 lesions in the overscaling group were significantly small (20 mm vs 28 mm; P < 0.001), and the small lesion size was influential on the overscaling (P = 0.002).

CONCLUSION

Lesions indicated for colorectal ESD tended to be underestimated in large tumors, but overestimated in small ones. This discrepancy appears worth understanding for optimal procedural preparation.

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.).

Endoscopic ultrasound-based application system for predicting endoscopic resection-related outcomes and diagnosing subepithelial lesions: Multicenter prospective study

OBJECTIVES

Subepithelial lesions (SELs) are associated with various endoscopic resection (ER) outcomes and diagnostic challenges. We aimed to establish a tool for predicting ER-related outcomes and diagnosing SELs and to investigate the predictive value of endoscopic ultrasound (EUS).

METHODS

Phase 1 (system development) was performed in a retrospective cohort (n = 837) who underwent EUS before ER for SELs at eight hospitals. Prediction models for five key outcomes were developed using logistic regression. Models with satisfactory internal validation performance were included in a mobile application system, SEL endoscopic resection predictor (SELERP). In Phase 2, the models were externally validated in a prospective cohort of 200 patients.

RESULTS

An SELERP was developed using EUS characteristics, which included 10 models for five key outcomes: post-ER ulcer management, short procedure time, long hospital stay, high medication costs, and diagnosis of SELs. In Phase 1, 10 models were derived and validated (C-statistics, 0.67-0.99; calibration-in-the-large, -0.14-0.10; calibration slopes, 0.92-1.08). In Phase 2, the derived risk prediction models showed convincing discrimination (C-statistics, 0.64-0.73) and calibration (calibration-in-the-large, -0.02-0.05; calibration slopes, 1.01-1.09) in the prospective cohort. The sensitivities and specificities of the five diagnostic models were 68.3-95.7% and 64.1-83.3%, respectively.

CONCLUSION

We developed and prospectively validated an application system for the prediction of ER outcomes and diagnosis of SELs, which could aid clinical decision-making and facilitate patient-physician consultation. EUS features significantly contributed to the prediction.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, http://www.chictr.org.cn (ChiCTR2000040118).

Predictors of severe submucosal fibrosis during endoscopic submucosal dissection in patients with ulcerative colitis: Retrospective cohort study

OBJECTIVES

Severe submucosal fibrosis is a crucial technical difficulty encountered during endoscopic submucosal dissection (ESD) in patients with ulcerative colitis (UC). We aimed to identify predictors of severe submucosal fibrosis in patients with UC.

METHODS

We retrospectively included 55 tumors resected using ESD from 48 consecutive patients with UC. We analyzed the clinicopathological characteristics and treatment outcomes between the F0/1 (none to mild submucosal fibrosis) group (n = 28) and F2 (severe submucosal fibrosis) group (n = 27).

RESULTS

No significant difference was found between the F0/1 and F2 groups in en bloc resection rate (100% vs. 96%, P = 0.49), the R0 resection rate (100% vs. 93%, P = 0.24), and the dissection speed (0.18 vs. 0.13 cm2 /min, P = 0.07). Intraoperative perforation was more common in the F2 group (30%) than in the F0/1 group (8%; P = 0.01). Multivariable analysis showed that a longer duration of UC (≥10 years; odds ratio [OR] 6.11; 95% confidence interval [CI] 1.20-31.03; P = 0.03) and scarring of background mucosa of the tumor (OR 39.61; 95% CI 3.91-400.78; P < 0.01) were independent predictors of severe submucosal fibrosis.

CONCLUSION

Long UC duration and scarring background mucosa were predictors of severe submucosal fibrosis associated with perforation during ESD.

Endoscopic full-thickness resection vs. endoscopic submucosal dissection of residual/recurrent colonic lesions on scars: a retrospective Italian and Japanese comparative study

BACKGROUND AND AIMS

Endoscopic treatment of recurrent/residual colonic lesions on scars is a challenging procedure. In this setting, endoscopic submucosal dissection (ESD) is considered the first choice, despite a significant rate of complications. Endoscopic full-thickness resection (eFTR) has been shown to be well-tolerated and effective for these lesions. The aim of this study is to conduct a comparison of outcomes for resection of such lesions between ESD and eFTR in an Italian and a Japanese referral center.

METHODS

From January 2018 to July 2020, we retrospectively enrolled patients with residual/recurrent colonic lesions, 20 treated by eFTR in Italy and 43 treated by ESD in Japan. The primary outcome was to compare the two techniques in terms of en-bloc and R0-resection rates, whereas complications, time of procedure, and outcomes at 3-month follow-up were evaluated as secondary outcomes.

RESULTS

R0 resection rate was not significantly different between the two groups [18/20 (90%) and 41/43 (95%); P= 0.66]. En-bloc resection was 100% in both groups. No significant difference was found in the procedure time (54 min vs. 61 min; P= 0.9). There was a higher perforation rate in the ESD group [11/43 (26%) vs. 0/20 (0%); P= 0.01]. At the 3-month follow-up, two lesions relapsed in the eFTR cohort and none in the ESD cohort (P= 0.1).

CONCLUSION

eFTR is a safer, as effective and equally time-consuming technique compared with ESD for the treatment of residual/recurrent colonic lesions on scars and could become an alternative therapeutic option for such lesions.

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.

Clinical outcomes of endoscopic submucosal dissection for giant rectal tumors larger than 8 cm: A European referral center experience

BACKGROUND AND AIMS

To date, western data on colorectal ESD are limited. This study aimed to assess the efficacy and safety of rectal ESD for superficial lesions ≥ 8 cm.

METHODS

A total of 138 superficial rectal neoplasms treated by ESD were allocated in two groups: 25 in the "giant" ESD group and 113 in the control group.

RESULTS

En bloc resection was achieved in 96% of cases in both groups. En bloc R0 resection rate was similar between the "giant" ESD group and the control group (84% vs 86%; p: 0.5) and curative resection was higher in the control group (81%) than in "giant" ESD group (68%) without reaching statistical significance (p: 0.2). Dissection time was significantly longer in the "giant" ESD group (251 vs 108 min; p <0.001), however, dissection speed was significantly higher (0.35 vs 0.17 cm2/min; p: 0.02).). Post-ESD stenosis was observed in 2 patients from the "giant" ESD group (8% vs 0% of control group, p: 0.03). No significant differences were found in delayed bleeding, perforation, local recurrences, and need for additional surgery.

CONCLUSIONS

ESD for superficial rectal tumors ≥ 8 cm is a feasible, safe, and effective therapeutic option.

Difficult colorectal polypectomy: Technical tips and recent advances

Colonoscopy has been shown to be an effective modality to prevent colorectal cancer (CRC) development. CRC reduction is achieved by detecting and removing adenomas, which are precursors of CRC. Most colorectal polyps are small and do not pose a significant challenge for trained and skilled endoscopists. However, up to 15% of polyps are considered "difficult", potentially causing life-threatening complications. A difficult polyp is defined as any polyp that is challenging for the endoscopist to remove owing to its size, shape, or location. Advanced polypectomy techniques and skills are required to resect difficult colorectal polyps. There were various polypectomy techniques for difficult polyps such as endoscopic mucosal resection (EMR), underwater EMR, Tip-in EMR, endoscopic submucosal dissection (ESD), or endoscopic full-thickness resection. The selection of the appropriate modality depends on the morphology and endoscopic diagnosis. Several technologies have been developed to aid endoscopists in performing safe and effective polypectomies, especially complex procedures such as ESD. These advances include video endoscopy system, equipment assisting in advanced polypectomy, and closure devices/techniques for complication management. Endoscopists should know how to use these devices and their availability in practice to enhance polypectomy performance. This review describes several useful strategies and tips for managing difficult colorectal polyps. We also propose the stepwise approach for difficult colorectal polyps.

Endoscopic submucosal tunnel dissection vs conventional endoscopic submucosal dissection for large colorectal neoplasms: a single-centre retrospective study

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) is still not widely used due to its technical difficulty and the risk of complications. Several techniques, such as traction techniques, pocket techniques and others, have been proposed to facilitate it. One modified pocket technique especially suitable for large lesions is endoscopic submucosal tunnel dissection (ESTD). The aim of this study was to evaluate the safety and efficacy of ESTD and compare ESTD to the conventional ESD (CESD) for treating large colorectal lesions.

METHODS

The charts of consecutive patients referred to the Arcispedale Santa Maria Nuova (Reggio Emilia, Italy) for colorectal ESD between January 2014 and February 2021 for colorectal neoplasms > 40 mm were retrospectively analysed. The primary outcome of the study was the en bloc resection rate. Secondary outcomes were complete and curative resection rates, procedure speed, the adverse events rate and the recurrence rate.

RESULTS

There were 59 patients (M:F ratio 29:30, median age 70 years [range 50-93 years]). Of 59 colorectal lesions > 40 mm, 25 were removed by ESTD and 34 by CESD. The en bloc resection rate was 100% in both groups and the complete resection rate was similar (ESTD 92% vs CESD 97.1%, p = 0.569), while the curative resection rate was higher in the CESD group, but not significantly (94.1% vs 76%, p = 0.061). Procedure speed was significantly faster with ESTD (22 vs 17 mm²/min, p = 0.045), and the overall incidence of adverse events was low (6.8%). Eight patients were referred to surgery due to non-curative resection. During follow-up, no recurrence was observed in either treatment group.

CONCLUSION

ESTD achieves a very high en bloc resection rate and is faster than CESD.

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.

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.

Current status of endoscopic full-thickness resection with the full-thickness resection device

Endoscopic full-thickness resection (EFTR) using the full-thickness resection device (FTRD) is an integral part of diagnostic and therapeutic endoscopy. Since its market launch in Europe in 2014, its safety and effectiveness have been proven in numerous studies. Adaptations in design as well as new techniques, such as hybrid EFTR, expand the spectrum of the FTRD system. The following review is intended to provide an overview of the clinical application and current evidence of EFTR with the FTRD system.

Endoscopic submucosal dissection for colorectal polyps: outcome determining factors

BACKGROUND

Endoscopic submucosal dissection (ESD) has gained increasing popularity in the management of complicated colorectal polyps. However, clinical outcomes for ESD have remained highly inconsistent worldwide. This study investigated and analysed factors that significantly affect ESD outcomes.

METHODS

We conducted a single-centred retrospective study on 220 colorectal polyps removed by ESD from 1st January 2016 to 31st December 2020. Data were collected and retrieved from clinical records. Variables studied included patient demographics, ESD technicalities and polyp characteristics. The primary outcome was completeness of resection based on en bloc and R0 resection rates. The secondary outcomes were recurrence, complications and hospital stay. Further analysis was performed for significant outcome determining factors.

RESULTS

The en bloc resection and R0 resection rates were 97.3% and 65% respectively. Intraprocedural and delayed perforation rates were 3.2% and 0.5% respectively. Intraprocedural and delayed bleeding rates were both 1.8%. Post-polypectomy syndrome rate was 2.7%. The median hospital stay was 4 days. Submucosal fibrosis was a significant determining factor for lower en bloc resection (p = 0.004), lower R0 resection (p = 0.002), intraprocedural perforation (p = 0.001), intraprocedural bleeding (p = 0.025) and post-polypectomy syndrome (p = 0.039). Hybrid snaring was associated with lower en bloc resection (p < 0.001), while longer ESD time was associated with lower R0 resection (p = 0.003) and post-polypectomy syndrome (p = 0.025). Other significant factors for post-polypectomy syndrome included young age (p = 0.021) and large polyp size (p = 0.018). Secondary analysis showed that submucosal fibrosis was significantly associated with non-granular lesions (p < 0.001) and prior biopsy (p = 0.003).

CONCLUSION

Submucosal fibrosis, hybrid snaring, ESD time, age and polyp size were significant outcome determining factors for ESD. By identifying these factors, strategies may be formulated to improve ESD outcomes.

Outcomes of endoscopic submucosal dissection in patients who develop metachronous superficial esophageal squamous cell carcinoma close to a post-endoscopic submucosal dissection scar

BACKGROUND

The presence of post-endoscopic submucosal dissection (ESD) scars renders complete metachronous superficial esophageal squamous cell carcinoma resection difficult. We aimed to identify the risk factors for incomplete resection of metachronous esophageal squamous cell carcinoma close to the post-ESD scar by ESD.

METHODS

We enrolled patients who developed post-ESD superficial esophageal squamous cell carcinoma at Hiroshima University Hospital between January 2006 and March 2020. We analyzed the outcomes and risk factors of incomplete resection between patients whose lesions were close to (close-to group) and away from (away-from group) the post-ESD scar.

RESULTS

We included 111 patients with 212 lesions. The close-to group had a significantly lower complete resection rate (88.6% [62/70] vs. 98.6% [69/70], p = 0.033), longer procedure time (80.2 ± 47.2 min vs. 60.4 ± 29.3 min, p < 0.01), higher proportion of lesions with severe fibrosis (72.9% [51/70] vs. 5.7% [4/70], p < 0.01), and higher intraoperative bleeding rate (78.6% [55/70] vs. 60.0% [42/70], p = 0.027) than the away-from group. There was no significant difference in the rate of local recurrence, muscle injury, perforation, and stenosis as well as the pathological tumor depth between the groups. Of the 92 lesions in the close-to group, the proportion of lesions located on the oral side of the post-ESD scar significantly affected the incidence of incomplete resection (91.7% [11/12] vs. 53.8% [43/80], p = 0.013).

CONCLUSIONS

Complete resection was more difficult for lesions located on the oral side of the post-ESD scar.

Novel image enhancement technology that helps find bleeding points during endoscopic submucosal dissection of gastric neoplasms

BACKGROUND AND AIM

The management of bleeding during endoscopic submucosal dissection (ESD) is critical and related to the procedure time. We collaborated on a new image enhancement algorithm with parameter optimization for clinical use being developed by FUJIFILM Co. and processed white light image data offline to evaluate the effectiveness of this technology. This study aims to evaluate the clinical usefulness of this technology.

METHODS

Eighteen video scenes of bleeding points from five gastric ESDs were selected and processed by the new image enhancement algorithm. The time until a bleeding point was found, visibility of a bleeding point, and color abnormality of the submucosal layer were evaluated by ESD experts, ESD trainees, and endoscopy trainees. The color differences between the bleeding point and the surroundings in CIE-L*a*b* color space were calculated in the original and enhanced images.

RESULTS

The time until a bleeding point was found in the enhanced videos was significantly shorter than that in the original videos (11.10 s vs 13.85 s) (P = 0.017). On a 5-point (-2 to +2) Likert scale of visibility, the enhanced image was slightly superior to the original (+0.45), and the appearance of the submucosa was comparable between images (+0.14). The color difference among the bleeding areas on the enhanced images was significantly larger than that on the original images (10.93 vs 8.36).

CONCLUSION

This novel image enhancement algorithm emphasizes the color difference between a bleeding point and the surrounding area, which would help find bleeding points faster during ESD for the less experienced endoscopists.

Underwater endoscopic submucosal dissection and hybrid endoscopic submucosal dissection as rescue therapy in difficult colorectal cases

Background and study aims  Colorectal endoscopic submucosal dissection (ESD) is still not widely used due to its technical difficulty and the risk of complications. Rescue therapies such as hybrid ESD (H-ESD) have been proposed for very difficult cases, as has underwater ESD (U-ESD). This study evaluated the safety and efficacy of H-ESD and U-ESD in difficult cases. Patients and methods  The hospital charts of consecutive patients referred for colorectal ESD between January 2014 and February 2021 because they were considered difficult cases were retrospectively analyzed. The primary outcome of the study was en bloc resection rate; secondary outcomes were the rate of complete resection, procedure speed, and incidence of adverse events (AEs). Results  Fifty-nine colorectal neoplasms were considered, 22 of which were removed by U-ESD and 37 by H-ESD. The en bloc resection rate in the U-ESD group was 100 %, while it was 59.5 % in the H-ESD group. Dissection speed was 17.7mm ² /min in the U-ESD group and 8.3 mm ² /min in the H-ESD group. The AE rate was low in the U-ESD group and moderately high during H-ESD (5 % and 21.6 %, respectively; and perforation rate 0 % and 10.8 %, respectively). Larger lesions were treated with U-ESD, while more fibrotic ones were treated with H-ESD. Conclusions  U-ESD and H-ESD are both effective and safe techniques in difficult colorectal situations. U-ESD is particularly effective and fast for large lesions when it is not possible to obtain comfortable knife position, while H-ESD is more suitable for very fibrotic lesions.

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.

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 Management of Complex Colorectal Polyps: Current Insights and Future Trends

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

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.

Safety and efficacy of water pressure endoscopic submucosal dissection for colorectal tumors with submucosal fibrosis (with video)

BACKGROUND AND AIMS

Colorectal neoplasms with submucosal fibrosis are the most challenging targets of endoscopic resection. Water pressure endoscopic submucosal dissection (WP-ESD) is a recently introduced procedure that has several advantages over conventional endoscopic submucosal dissection (C-ESD). This study aimed to assess the efficacy and safety of WP-ESD for fibrotic colorectal neoplasms.

METHODS

This retrospective observational study investigated 133 colorectal neoplasms expected to have submucosal fibrosis that were resected by WP-ESD or C-ESD between April 2012 and April 2020. Eighty-seven lesions after endoscopic or surgical treatment, 18 with biopsy scar with fold convergence and 28 in patients with ulcerative colitis, were included. The differences in treatment outcomes, including procedure time and adverse event proportions, between the WP-ESD and C-ESD groups were analyzed. The clinical course after perforation using WP-ESD was also evaluated, including postprocedural multidetector CT findings obtained immediately after WP-ESD.

RESULTS

Severe submucosal fibrosis was observed in 96 lesions (72.2%). The median procedure time was significantly shorter in the WP-ESD group than in the C-ESD group (43.5 minutes [interquartile range {IQR}, 32.8-73] vs 72 minutes [IQR, 45-105]; P = .0041). The multivariate analysis revealed WP-ESD as an independent factor for a short procedure time (odds ratio, 2.90; 95% confidence interval, 1.28-6.55). The proportions of post-ESD electrocoagulation syndrome (11.6% vs 13.1%) and perforation (20.4% vs 22.8%) were similar between the groups. Four of 11 patients with perforation who underwent WP-ESD showed fluid collection on postprocedural multidetector CT images.

CONCLUSIONS

WP-ESD can shorten procedure time for treating fibrotic colorectal neoplasms.

Double-clip traction for colonic endoscopic submucosal dissection: a multicenter study of 599 consecutive cases (with video)

BACKGROUND AND AIMS

Colonic endoscopic submucosal dissection (ESD) is particularly challenging and limited to a few expert centers. We recently conducted a pilot study on improvement of colonic ESD with systematic use of a countertraction device (double-clip traction with rubber band [DCT-ESD]).

METHODS

A French prospective multicenter study was conducted between March 2017 and September 2019, including all consecutive cases of naive colonic ESD. Since the first case of DCT-ESD in March 2017, all cases of colonic ESD have been performed using the DCT-ESD strategy in the 3 centers involved in the study.

RESULTS

Five hundred ninety-nine lesions with a mean size of 53 mm were included in this study, resected by 5 operators in 3 centers. The en bloc, R0, and curative resection rates were 95.7%, 83.5%, and 81.1%, respectively. The adverse event rates were 4.9% for perforation and 4.2% for postprocedure bleeding. Between 2017 and 2019, the rates of R0 and curative resections increased significantly from 74.7% in 2017 to 88.4% in 2019 (P = .003) and from 72.6% in 2017 to 86.3% in 2019 (P = .004), respectively. Procedure duration and speed of resection were 62.4 minutes and 39.4 mm²/minute, respectively. No differences were noted between operators.

CONCLUSION

DCT-ESD is a safe and reproducible technique, with results comparable with those of the large Japanese teams with speed of resection twice as high as previously reported studies. The DCT strategy is promising, cheap, and seems to be reproducible. Physicians performing colonic ESD should be aware of this promising tool to improve their results in ESD.

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.

Predictors for Submucosal Fibrosis in Patients With Superficial Squamous Esophageal Neoplasia Undergoing Endoscopic Submucosal Dissection

INTRODUCTION

Submucosal fibrosis greatly hinders the success of endoscopic submucosal dissection (ESD). This study determined ESD outcomes in patients with esophageal submucosal fibrosis and further explored the predictors.

METHODS

We retrospectively analyzed 163 patients with superficial squamous esophageal neoplasia. The degree of submucosal fibrosis was classified as follows: F0, none; F1, mild; and F2, severe. ESD outcomes as a function of the degree of submucosal fibrosis and biopsy were determined. The potential predictors of submucosal fibrosis were analyzed.

RESULTS

En bloc resection, R0 resection, and procedure time were significantly different between the F0-F2 groups (P = 0.009, P = 0.002, and P < 0.001, respectively). Perforation and immediate bleeding rates of F2 were significantly higher than the F0/F1 groups (P < 0.001 and P < 0.001, respectively). However, the nonbiopsy group vs the biopsy group and the delayed ESD group (postbiopsy >21 days) vs the early ESD group (postbiopsy ≤21 days) showed no statistical differences regarding the en bloc resection, R0 resection, and ESD complications (all P > 0.05). Further analysis indicated that it was not the biopsy history and delayed ESD (both P > 0.05), rather submucosal invasion vs intramucosal tumor (odds ratio = 4.534, P = 0.003) and current smoker vs nonsmoker (odds ratio = 2.145, P = 0.043) were independent risk factors for endoscopic submucosal fibrosis.

DISCUSSION

Esophageal submucosal fibrosis was shown to be closely related to unsatisfactory ESD outcomes. Biopsy history and delayed ESD had no adverse effect on submucosal fibrosis and ESD outcomes. Submucosal invasion and current cigarette smoking were predictors of submucosal fibrosis.

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.

Endoscopic submucosal dissection for colorectal neoplasms in proximity or extending to a diverticulum

BACKGROUND AND AIMS

At specialized facilities, endoscopic submucosal dissection (ESD) has currently been performed even for difficult cases such as tumors extending to a diverticulum that previously required surgery. This study aims to classify the type of lesion according to the degree of infiltration to a diverticulum and assessed the safety and efficacy of ESD for each type of lesion.

METHODS

We retrospectively reviewed ESD for lesions at NTT Medical Center Tokyo between January 2014 and April 2019. Lesions were classified as follows: Type 1: lesions in contact with or within 3 mm of the edge of a diverticulum; Type 2: lesions that partially infiltrated into a diverticulum; and Type 3: lesions that infiltrated into and completely covered the diverticulum. Furthermore, ESD strategies were divided into A and B, which indicates that a lesion was resected separately from the diverticulum and along the entire diverticulum, respectively. The clinicopathological characteristics and clinical outcomes were analyzed according to the strategy.

RESULTS

A total of 47 lesions satisfied inclusion criteria (19 Type 1, 12 Type 2, and 16 Type 3 lesions). 19 Type 1 and 8 Type 2 lesions were resected using Strategy A, while 4 Type 2 and 16 Type 3 lesions were resected using Strategy B. En bloc resection was achieved in all cases. In Strategy A, the R0 resection rate was 96.3% and the curative resection rate was 88.9%. On the contrary, in Strategy B, the R0 resection rate was 95.0% and the curative resection rate was 90.0%. In Strategy B, one of the patients developed post-operative bleeding that required endoscopic hemostasis; another patient developed delayed perforation that required emergency surgery.

CONCLUSIONS

ESD for colorectal neoplasms in proximity or extending to a diverticulum is challenging, but this procedure can be a safe and effective therapeutic option.

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.

Hybrid endoscopic submucosal dissection: An alternative resection modality for large laterally spreading tumors in the cecum?

BACKGROUND

Endoscopic resection for large, laterally spreading tumors (LSTs) in the cecum is challenging. Here we report on the clinical outcomes of hybrid endoscopic submucosal dissection (ESD) in large cecal LSTs.

METHODS

We retrospectively reviewed data from patients with cecal LSTs ≥ 2 cm who underwent ESD or hybrid ESD procedures between January of 2008 and June of 2019. We compared the baseline characteristics and clinical outcomes, including procedure time, the en bloc and complete resection rates, and adverse events.

RESULTS

A total of 62 patients were enrolled in the study. There were 27 patients in the ESD group and 35 patients in the hybrid ESD group, respectively. Hybrid ESD was more used for lesions with submucosal fibrosis. No other significant differences were found in patient characteristics between the two groups. The hybrid ESD group had a significantly shorter procedure time compared with the ESD group (27.60 ± 17.21 vs. 52.63 ± 44.202 min, P = 0.001). The en bloc resection rate (77.1% vs. 81.5%, P = 0.677) and complete resection rate (71.4% vs. 81.5%, P = 0.359) of hybrid ESD were relatively lower than that of the ESD group in despite of no significant difference was found. The perforation and post-procedure bleeding rate (2.9% vs. 3.7%, P = 0.684) were similar between the two groups. One patient perforated during the ESD procedure, which was surgically treated. One patient in the hybrid ESD group experienced post-procedure bleeding, which was successfully treated with endoscopic hemostasis. Post-procedural fever and abdominal pain occurred in six patients in the ESD group and five patients in the hybrid ESD group. One patient in the ESD group experienced recurrence, which was endoscopically resected.

CONCLUSION

The results of this study indicate that hybrid ESD may be an alternative resection strategy for large cecal LSTs with submucosal fibrosis.

Salvage endoscopic submucosal dissection for local residual/recurrent colorectal tumor after endoscopic resection: Large multicenter 10-year study

OBJECTIVES

For local residual/recurrent and endoscopic resection (ER) interrupted colorectal tumors, endoscopic retreatment is often difficult due to severe submucosal fibrosis. Endoscopic submucosal dissection (ESD) can achieve en bloc resection, even for tumors with severe submucosal fibrosis, although it is a risk factor for incomplete resection and perforation. We aimed to determine the safety and efficacy of colorectal ESD for local residual/recurrent tumors including ER interrupted tumors from a large multicenter study.

METHODS

From January 2008 until December 2018, 3,937 colorectal tumors were resected by ESD at the Hiroshima GI Endoscopy Research Group. From this group, 81 local residual/recurrent tumors and 21 ER interrupted tumors were included. We analyzed ESD outcomes, particularly the difference between the early and late phases and re-recurrence after ESD for local residual/recurrent tumors.

RESULTS

For local residual/recurrent tumors, en bloc and R0 resection rates were 95% (77/81) and 90% (73/81), respectively. The intraoperative perforation rate was 6% (5/81), and one patient required surgery. The delayed perforation rate was 2% (2/81), and one patient required surgery. For ER interrupted tumors, both the en bloc and R0 resection rates were 86% (18/21), with no major adverse events. For local residual/recurrent and ER interrupted tumors, the intraoperative perforation rate was significantly lower in the late phase compared with the early phase. Following curative resection for local residual/recurrent tumors, no local re-recurrences occurred.

CONCLUSIONS

Colorectal ESD is an effective treatment for local residual/recurrent and ER interrupted tumors.

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.

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

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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