The submucosal fibrosis: what does it mean for colorectal endoscopic submucosal dissection?

Outcomes of Colonic Endoscopic Submucosal Dissection and Advanced Tissue Resection in Obese Patients: An Analysis of a Large Western Cohort

BACKGROUND AND AIM

Colonic endoscopic submucosal dissection (ESD) and advanced tissue resection (ATR) in obese patients present challenges, including limited scope maneuverability, instability from abdominal fat, and slower dissection due to poor conductivity of submucosal fat. This study aims to assess the impact of obesity on colonic ESD outcomes in a large Western cohort.

METHOD

This retrospective study analyzed patients who underwent colonic ESD and ATR at a US tertiary institution from April 2017 to July 2024. Patients were categorized by body mass index (BMI): control (< 25 kg/m2), overweight (25 ≤ BMI < 30 kg/m2), and obese (≥ 30 kg/m2). Multinomial logistic regression and univariate analysis were performed to evaluate the impact of weight status on clinical success, procedure time, and adverse events.

RESULTS

A total of 637 patients were included (Control: 175, Overweight: 227, Obese: 235). En bloc resection (86.9% vs. 82.4% vs. 85.1%, P = 0.77) and R0 resection (78.9% vs. 72.2% vs. 74.5%, P = 0.16) were similar across groups. Obese patients had a significantly lower R0 resection rate for left-sided colonic lesions (P = 0.046). Also, obese patients more frequently required an overtube for dissection, especially for right-sided lesions (80% vs. 66%, P = 0.04). Procedure times were similar (P = 0.445), and 74.4% were safely discharged on the same day. Lack of defect closure (OR 3.072, CI 1.382-6.828) and longer procedure time (OR 1.017, CI 1.011-1.023) predicted post-procedure admission. No significant differences in adverse events were observed.

CONCLUSION

Obese patients had a significantly lower R0 resection rate for left-sided colonic lesions and frequently required an overtube to facilitate the dissection of right-sided colonic lesions.

Risk Factors for Perforation in Endoscopic Treatment for Early Colorectal Cancer: A Nationwide ENTER-K Study

Background/Aims

Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC.

Methods

This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC.

Results

This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival.

Conclusions

Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Learning curve of colorectal endoscopic submucosal dissection of an endoscopist experienced hands-on training in Japan

BACKGROUND AND AIM

Colorectal endoscopic submucosal dissection is a technically demanding procedure with a steep learning curve. In Japan, the National Cancer Center Hospital allows overseas doctors to participate in hands-on training. We aimed to assess the colorectal endoscopic submucosal dissection performance and learning curve of an endoscopist who participated in hands-on training.

METHODS

In this retrospective analysis using a prospectively collected database, 100 consecutive superficial colorectal tumors from 100 patients treated with endoscopic submucosal dissection by a colorectal surgeon between January 2020 and May 2024 were included. The cases were grouped into three learning periods: phase I (the initial 30 cases under local expert supervision before training in Japan), phase II (the middle 30 cases), and phase III (the last 40 cases). The primary outcome was resection speed.

RESULTS

The median resection speed was 5, 11.7, and 13.2 cm2/h in phases I, II, and III, respectively. In matched data, the resection speeds in phases II and III were higher than that in phase I (P = 0.02 and P < 0.001, respectively). En bloc and R0 resection rates were 99% and 95%, respectively. The en bloc resection, R0 resection, and complication rates were not different between phases. Cumulative sum analysis of the resection speed revealed that proficiency was achieved after 36 cases.

CONCLUSIONS

An endoscopist who underwent a tutored approach and hands-on training in Japan achieved the proficiency benchmarks for colorectal endoscopic submucosal dissection after 36 cases. However, the endoscopist's extensive experience before training may contribute to excellent outcomes.

Feasibility, safety and efficacy of endoscopic submucosal dissection for recurrent superficial rectal neoplastic lesions after transanal microsurgery

BACKGROUND AND AIMS

We aimed to evaluate the feasibility, safety and efficacy of endoscopic submucosal dissection for recurrent rectal neoplastic lesions after transanal microsurgery of superficial rectal neoplasms.

METHODS

Multicenter retrospective study.

MAIN OUTCOMES

recurrence at first endoscopic follow-up, En bloc, R0 and curative resections.

RESULTS

39 patients were included. 71 % percent of lesions were located in the lower rectum, 57 % reached the pectineal line. 67 % were laterally spreading tumor granular type, 33 % were protruding lesions. Median size was 41 mm (IQR 30 - 60). Median operation time was 70 min (IQR 35 - 97). 92 % were successfully resected en bloc. R0 and curative resection rates were 77 % and 71 %, respectively. Perirectal fat was visualized in 10 patients, none of them required surgery. One significant hematochezia (3 %), two stenosis (6 %) and one untreatable anal incontinence (3 %) occurred. Median hospital stay after endoscopic submucosal dissection was 2 days (IQR 1-2). Median period for the first endoscopy follow-up was 6 months (IQR 4-8). A single post endoscopic submucosal dissection recurrence adenoma was found during follow-up (3 %), occurring after a non-en bloc resection.

CONCLUSION

Endoscopic submucosal dissection is a good option for safely achieving high rates of complete en bloc resection in cases of recurrent superficial rectal tumor after transanal microsurgery.

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.

Development and validation of a predictive model for submucosal fibrosis in patients with early gastric cancer undergoing endoscopic submucosal dissection: experience from a large tertiary center

BACKGROUND

Submucosal fibrosis is associated with adverse events of endoscopic submucosal dissection (ESD). The present study mainly aimed to establish a predictive model for submucosal fibrosis in patients with early gastric cancer (EGC) undergoing ESD.

METHODS

Eligible patients with EGC, identified at Qilu Hospital of Shandong University from April 2013 to December 2023, were retrospectively included and randomly split into a training set and a validation set in a 7:3 ratio. Logistic regression analyses were used to pinpoint the risk factors for submucosal fibrosis. A nomogram was developed and confirmed using receiver operating characteristic (ROC) curves, calibration plots, Hosmer-Lemeshow (H-L) tests, and decision curve analysis (DCA) curves. Besides, a predictive model for severe submucosal fibrosis was further conducted and tested.

RESULTS

A total of 516 cases in the training group and 220 cases in the validation group were recruited. The nomogram for submucosal fibrosis contained the following items: tumour location (long axis), tumour location (short axis), ulceration, and biopsy pathology. ROC curves showed high efficiency with an area under the ROC of 0.819 in the training group, and 0.812 in the validation group. Calibration curves and H-L tests indicated good consistency. DCA proved the nomogram to be clinically beneficial. Furthermore, the four items were also applicable for a nomogram predicting severe fibrosis, and the model performed well.

CONCLUSION

The predictive models, initially constructed in this study, were validated as convenient and feasible for endoscopists to predict submucosal fibrosis and severe fibrosis in patients with EGC undergoing ESD.

Hybrid Versus Conventional Colorectal Endoscopic Submucosal Dissection: A Multicenter Randomized Controlled Trial (Short-Endoscopic Submucosal Dissection)

INTRODUCTION

Hybrid endoscopic submucosal dissection (H-ESD), which utilizes ESD knife along with snare-based resection, has been developed to overcome the technical complexity of conventional ESD (C-ESD). The aim of this study was to compare the therapeutic outcomes of H-ESD vs C-ESD for nonpedunculated colorectal lesions ≥20 mm in size.

METHODS

We conducted a multicenter randomized controlled trial to compare H-ESD and C-ESD (Short-ESD trial). Patients with colorectal lesions between 20 and 50 mm in size were randomly assigned (1:1) to H-ESD or C-ESD. Primary outcome was procedure time/speed. Secondary outcomes were en bloc and complete (R0) resection rates and adverse event rates.

RESULTS

A total of 89 patients (median age 63 years; 49.3% women) with the median polyp size of 30 mm underwent H-ESD (n = 40) and C-ESD (n = 49). The mean procedure time of H-ESD was significantly shorter than that of C-ESD (41.1 ± 16.3 vs 54.3 ± 28.2 minutes; P = 0.007). The en bloc and R0 resection rates trended lower in the H-ESD vs C-ESD groups (77.5% vs 87.8%; P = 0.26% and 72.5% vs 79.6%; P = 0.46) without reaching statistical significance. Adverse event rate was similar between H-ESD and C-ESD (10% vs 8.2%; P = 1.00).

DISCUSSION

Both H-ESD and C-ESD were safe and effective for resection of large colorectal lesions. H-ESD was associated with a shorter procedure time. H-ESD may represent a viable alternative to C-ESD, with the main advantage being easy applicability of a snare-based technique for colorectal lesions. Future studies are needed to further define the most suitable lesions for H-ESD, as to optimize efficiency and safety without compromising resection outcomes. ClinicaTrials.gov NCT NCT05347446.

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 Post-Endoscopic Submucosal Dissection Electrocoagulation Syndrome in Patients with Colorectal Neoplasms: A Multicenter, Large-Scale, Retrospective Cohort Study by the Honam Association for the Study of Intestinal Disease (HASID)

Background and Objectives: Colorectal endoscopic submucosal dissection (ESD) is an effective technique for removing colorectal neoplasms with large or cancerous lesions. However, there are few studies on post-ESD electrocoagulation syndrome (PECS), a complication of colorectal ESD. Therefore, this study aimed to investigate the various risk factors for PECS after colorectal ESD. Materials and Methods: We retrospectively analyzed the medical records of 1413 lesions from 1408 patients who underwent colorectal ESD at five tertiary hospitals between January 2015 and December 2020. We investigated the incidence and risk factors associated with PECS. Based on the data, we developed a risk-scoring model to predict the risk of PECS after colorectal ESD. Results: The incidence rate of PECS was 2.6% (37 patients). In multivariate analysis, the use of anti-platelet agents (odds ratio (OR), 2.474; 95% confidence interval (CI), 1.088-5.626; p < 0.031), a lesion larger than 6 cm (OR 3.755; 95% CI, 1.237-11.395; p = 0.028), a deep submucosal invasion (OR 2.579; 95% CI, 1.022-6.507; p = 0.045), and an ESD procedure time ≥ 60 min (OR 2.691; 95% CI, 1.302-5.560; p = 0.008) were independent risk factors of PECS after colorectal ESD. We developed a scoring model for predicting PECS using these four factors. As the score increased, the incidence of PECS also increased, from 1.3% to 16.6%. PECS occurred more frequently in the high-risk group (≥2) (1.8% vs. 12.4%, p < 0.001). Conclusions: In this study, the risk factors for PECS after colorectal ESD were the use of anti-platelet agents, a lesion larger than 6 cm, a deep submucosal invasion, and an ESD procedure time ≥ 60 min. The risk-scoring model developed in this study using these factors could be effective in predicting and preventing PECS.

Delays in definitive endoscopic resection of previously manipulated colorectal polyps as a risk factor for inferior resection outcomes

BACKGROUND AND AIMS

Manipulation of colorectal polyps by biopsy, incomplete resection, or tattoo placement under the lesion has been shown to cause submucosal fibrosis and associated inferior outcomes. The effect of delays between index manipulation and definitive resection on the incidence of fibrosis is unknown.

METHODS

Patients undergoing EMR of previously manipulated colorectal polyps ≥10 mm from 2016 to 2021 at a tertiary referral center were included. Time from index manipulation to definitive resection and the presence of fibrosis were noted. The effects of fibrosis on EMR outcomes were assessed.

RESULTS

Among 221 previously manipulated lesions (180 biopsy, 23 incomplete/failed resection, 1 tattoo under lesion, 17 multiple types of manipulation), 51 (23%) demonstrated fibrosis. Fibrotic lesions were found to have been resected significantly later than nonfibrotic lesions (76 vs 61 days; P = .014). In a multivariate analysis controlling for other predictors of fibrosis, each 2-week delay was associated with a 14% increase in the odds of fibrosis. Fibrotic lesions had inferior outcomes with a lower en-bloc resection rate (8% vs 24%; P = .014) and longer procedure time (71 vs 52 minutes; P < .001). Adverse event and recurrence rates were similar between groups.

CONCLUSIONS

Delays in definitive resection of previously manipulated polyps are associated with an increased incidence of fibrosis with time and associated inferior outcomes. Manipulation should be discouraged, and if it occurs, prompt referral and scheduling for definitive resection should be prioritized.

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.

Novel beagle model of gastric local fibrotic target lesions for the evaluation and training of endoscopic techniques

BACKGROUND

Novel endoscopic techniques used in the treatment of gastric lesions with local submucosal fibrosis need preclinical evaluation and training due to safety limitations. Therefore, the purpose of our study was to establish an animal model of gastric local fibrotic target lesions and assess its feasibility in the evaluation and training of endoscopic techniques.

METHODS

In six experimental beagles, a 50% glucose solution was injected into three submucosal areas of the fundus, body, and antrum of the stomach to create gastric local fibrotic target lesions (experimental group). On post-injection day (PID) 7, the injection sites were assessed endoscopically to confirm the presence of submucosal fibrosis formation, and the dental floss clip traction assisted endoscopic submucosal dissection (DFC-ESD) procedure was performed on the gastric local fibrotic target lesions to confirm its feasibility after endoscopic observation. The normal gastric mucosa of six control beagles underwent the same procedure (control group). All the resected specimens were evaluated by histological examination.

RESULTS

All 12 beagles survived without postoperative adverse events. On PID 7, 16 ulcer changes were observed at the injection sites (16/18) under the endoscope, and endoscopic ultrasonography confirmed the local submucosal fibrosis formation in all ulcer lesions. The subsequent DFC-ESD was successfully performed on the 32 gastric target lesions, and the mean submucosal dissection time in the ulcer lesions was greater than that in the normal gastric mucosa (15.3 ± 5.6 vs. 6.8 ± 0.8 min; P < 0.001). There was no difference in rates of en bloc resection, severe hemorrhage, or perforation between the two groups. Histological analysis of the ulcer lesions showed the absence of epithelial or muscularis mucosae and extensive submucosal fibrous tissue proliferations compared with normal gastric mucosa. Overall, endoscopists had high satisfaction with the realism and feasibility of the animal model.

CONCLUSION

We developed a novel animal model of gastric local fibrotic target lesions to simulate difficult clinical situations, which strongly appeared to be suitable for the preclinical evaluation and learning of advanced endoscopic techniques.

Is colorectal endoscopic submucosal dissection safe and effective for 15-19-mm tumors?

PURPOSE

The outcomes of colorectal endoscopic submucosal dissection (ESD) in 15-19-mm tumors are unclear. This study compared the effectiveness and safety of colorectal ESD for 15-19-mm tumors and tumors exceeding that size.

METHODS

From August 2018 to December 2020, 213 cases of colorectal tumors removed by colorectal ESD at a tertiary hospital were enrolled in this study. The cases were divided into two groups according to the pathologically measured size of the resected lesion: an intermediate group (15-19 mm, n = 62) and a large group (≥ 20 mm, n = 151). The en bloc resection rate, complete resection rate, and complications were investigated retrospectively.

RESULTS

The en bloc resection rate was significantly higher in the intermediate than large group (100% vs. 94%, p = 0.049), and the mean total procedure time was shorter in the intermediate than large group (29.2 [Formula: see text] 12.6 vs. 48.4 [Formula: see text] 28.8 min, p < 0.001). However, the mean procedure speed was significantly lower in the intermediate than large group (0.25 [Formula: see text] 0.10 vs. 0.28 [Formula: see text] 0.11 cm2/min, p = 0.031). The complete resection rate, post-procedural bleeding, and perforation rate were not significantly different between the two groups. In multivariate analyses, the total procedure time and mean procedure speed were significantly associated with lesion size.

CONCLUSION

Colorectal ESD of 15-19-mm lesions is effective, and has a shorter procedure time and higher en bloc resection rate than the same procedure for larger lesions.

Initial multicenter experience using a novel articulating through-the-scope traction device for endoscopic submucosal dissection

Background and study aims A single-operator, articulating, through-the-scope (TTS) traction device was recently developed to facilitate endoscopic submucosal dissection (ESD). Clinical data on the performance of this device are limited. We report an initial multicenter experience with ESD using this articulating TTS traction device. Patients and methods Retrospective analysis on all consecutive patients who underwent ESD using this traction device (T-ESD) at five centers between August 2021 and December 2022. Endpoints included: rates of en-bloc resection, R0 resection, curative resection, and adverse events. Results Thirty-six patients (median age 64.8 years; 47.2% women) underwent ESD (median lesion size 40 mm; interquartile range [IRQ]: 27.5-67.5) for lesions in the esophagus (n=2), stomach (n=8), sigmoid colon (n=6), and rectum (n=20). Submucosal fibrosis was encountered in one-third of the lesions (33.3%). Median ESD time was 104.6 minutes (IQR: 65-122). En-bloc, R0 and curative resection were achieved in 94.4%, 91.6%, and 97.2%, respectively. The single patient with non-curative resection of an invasive rectal adenocarcinoma underwent surgery. There were no cases of delayed bleeding or perforation. There was no recurrence on surveillance endoscopy (n=20) at a median of 6 months (IQR: 3.75-6). Conclusions This initial multicenter experience demonstrates high resection rates and excellent safety profile when performing ESD with this novel articulating TTS device. Dynamic real-time traction may lower the technical difficulty of ESD. Additional studies are needed to assess its cost-effectiveness and compare its usefulness with other traction devices and techniques during ESD.

Safety and feasibility of same-day discharge after endoscopic submucosal dissection: a Western multicenter prospective cohort study

BACKGROUND AND AIMS

Recent Western studies support the safety and efficacy of endoscopic submucosal dissection (ESD) for lesions throughout the GI tract. Although admission for observation after ESD is standard in Asia, a more selective approach may optimize resource utilization. We aimed to evaluate the safety and feasibility of same-day discharge (SDD) after ESD and factors associated with admission.

METHODS

This was a post hoc analysis of a multicenter, prospective cohort of patients undergoing ESD (2016-2021). The primary end points were safety of SDD and factors associated with post-ESD admission.

RESULTS

Of 831 patients (median age, 67 years; 57% male) undergoing 831 ESDs (240 performed in the esophagus, 126 in the stomach, and 465 in the colorectum; median lesion size, 44 mm), 588 (71%) were SDD versus 243 (29%) admissions. Delayed bleeding and perforation occurred in 12 (2%) and 4 (.7%) of SDD patients, respectively; only 1 (.2%) required surgery. Of the 243 admissions, 223 (92%) were discharged after ≤24 hours of observation. Interestingly, larger lesion size (>44 mm) was not associated with higher admission rate (odds ratio [OR], .5; 95% confidence interval [CI], .3-.8; P = .001). Lesions in the upper GI tract versus colon (OR, 1.7; 95% CI, 1.1-2.6; P = .01), invasive cancer (OR, 1.9; 95% CI, 1.2-3.1; P = .01), and adverse events (OR, 2.7; 95% CI, 1.5-4.8; P = .001) were independent factors for admission. Admissions were more likely performed by endoscopists with ESD volume <50 cases (OR, 2.1; 95% CI, 1.3-3.3; P = .001) with procedure time >75 minutes (OR, 13.5; 95% CI, 8.5-21.3; P < .0001).

CONCLUSIONS

SDD after ESD can be safe and feasible. Patients with invasive cancer, lesions in the upper GI tract, longer procedure times, or procedures performed by low-volume ESD endoscopists are more likely to be admitted postprocedure. Risk stratification of patients for SDD after ESD should help optimize resource utilization and enhance ESD uptake in the West. (Clinical trial registration number: NCT02989818.).

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 and Learning Curve in Endoscopic Submucosal Dissection of Rectal Neoplasms with Severe Fibrosis: Experience of a Western Center

<b><i>Introduction:</i></b> Endoscopic submucosal dissection (ESD) of lesions with severe submucosal fibrosis has been associated with worse outcomes, such as lower curative resection rate and higher incidence of adverse events. This study aims to investigate its true impact on rectal ESD performed in the West and to assess predictive factors of severe fibrosis. <b><i>Methods:</i></b> We conducted a retrospective study including all rectal ESDs performed at our tertiary center from January 2013 to January 2021. Lesions were grouped as nonsevere fibrosis or severe fibrosis. ESD outcomes, predictors of severe fibrosis, and the learning curve were evaluated. <b><i>Results:</i></b> ESD was performed in 195 lesions, 45 with severe fibrosis. Three resections were interrupted (one due to severe fibrosis). The presence of severe fibrosis was related to a significantly lower resection speed (16.93 mm²/min vs. 24.66 mm²/min, <i>p</i> = 0.007), en bloc (86.4% vs. 96.6%, <i>p</i> = 0.019), R0 (61.4% vs. 79.7%, <i>p</i> = 0.013), and curative (54.5% vs. 78.4%, <i>p</i> = 0.003) resection rates and a higher rate of hybrid ESD required to complete resection (13.6% vs. 2.0%, <i>p</i> = 0.005). No significant difference was noted regarding adverse events rate (18.2% vs. 8.1%, <i>p</i> = 0.09). Male sex, ulcerative colitis, pelvic radiotherapy, a lesion on the anastomotic site, previous manipulation, and deep submucosal invasion were independent predictors for severe fibrosis. En bloc resection rate improved during time (60.0% vs. 94.1%, <i>p</i> = 0.018). <b><i>Conclusions:</i></b> Severe submucosal fibrosis is an important factor related to noncurative resections and challenging rectal ESD. Factors predicting its severity are extremely important and could allow more experienced endoscopists to be assigned to more difficult cases, allowing safer procedures.

Comparison of precutting endoscopic mucosal resection and endoscopic submucosal dissection for large (20-30 mm) flat colorectal lesions

BACKGROUND AND AIM

The complete and safe removal of large (≥ 20 mm) colorectal lesions is an area of concern. Endoscopic submucosal dissection (ESD) effectively removes these lesions compared with endoscopic mucosal resection (EMR). However, ESD requires advanced techniques, longer procedure time, and high cost. Precutting EMR (EMR-P) is a modified EMR method that overcomes the limitations of EMR. This study aimed to compare the efficacy and safety of EMR-P and ESD in large (20-30 mm) flat colorectal lesions.

METHODS

This was a retrospective analysis of cases in which 20- to 30-mm flat colorectal lesions were resected at Seoul St. Mary's Hospital from January 2014 to December 2019. Propensity score matching was performed to control for possible confounders.

RESULTS

Two hundred and ninety-nine patients were included in this study. After matching, 90 patients were assigned to each group. There were no significant difference in complete resection rates (92.2% vs 92.2%, P = 1.000), en bloc resection rates (95.6% vs 97.8%, P = 0.682), and mean size of lesions (22.9 ± 3.1 mm vs 23.0 ± 3.1 mm, P = 0.867) between EMR-P and ESD. Procedure time was significantly shorter with EMR-P (11.0 ± 6.5 min vs 37.0 ± 19.3 min, P < 0.001). The adverse events rate was not significantly different between both groups. No local recurrence occurred in both groups.

CONCLUSIONS

Precutting EMR was not significantly different to ESD in terms of complete resection rate and en bloc resection rate for 20- to 30-mm flat colorectal lesions without fibrosis. Furthermore, EMR-P has shorter procedure time than ESD. EMR-P could be considered one of standard treatments for large flat colorectal lesions.

Impact of Procedure Time of Preceding Endoscopic Submucosal Dissection on the Difficulty of Laparoscopic Rectal Surgery

Objetive: 

In this study, we addressed which factors, including endoscopic submucosal dissection (ESD)–related parameters, affect the difficulty of laparoscopic rectal surgery.

Summary of background data: 

Endoscopic treatment for gastrointestinal cancer can cause inflammation, edema, and fibrosis formation in the surrounding tissue. Recently, we reported that preceding endoscopic treatment increased the volume of intraoperative blood loss and slightly prolonged the operative time of laparoscopic surgery for rectal cancer.

Methods: 

We retrospectively reviewed 24 consecutive patients who underwent ESD followed by laparoscopic surgery for rectal cancer in our hospital. Short-term surgical outcomes were evaluated by intraoperative blood loss and operative time for laparoscopic surgery. The correlations between the surgical outcomes and preoperative parameter were analyzed by multiple linear regression analyses.

Results: 

The patient cohort comprised 12 men and 12 women. The median distance between primary cancer and anal verge was 7 cm. The median procedure time of ESD was 120 minutes (21 available cases). Based on multiple linear regression analyses, the ESD procedure time (P = 0.007) and tumor location from the anal verge (P = 0.046) were independently predictive of intraoperative blood loss. On the other hand, only tumor location was found to be an independent predictor of surgical time (P = 0.014).

Conclusions: 

A long session of ESD for rectal cancer may make subsequent laparoscopic surgery difficult based on intraoperative blood loss.

Pocket-creation method improves efficacy of colorectal endoscopic submucosal dissection: a system review and meta-analysis

The pocket-creation method (PCM) is a new strategy for endoscopic submucosal dissection (ESD). The aim of this system review is to evaluate the clinical efficacy and safety of PCM-ESD compared to conventional ESD (C-ESD) for colorectal neoplasm lesions. We performed literature search using MEDLINE, EMBASE and CENTRAL database from inception to 15 February 2020. Studies provided comparison between PCM-ESD and C-ESD for colorectal neoplasm lesions were included. En bloc resection rate, R0 resection rate, occurrence rate of adverse events and operation speed/time were extracted from included studies. Pooled risk difference with 95% confidence intervals (CIs) was calculated in meta-analysis. Three cohort studies and one randomized control trial (RCT) were included, which contained 432 colorectal lesions removed by PCM-ESD and 959 lesions resected by C-ESD. PCM-ESD achieved significantly higher en bloc/R0 resection rate than C-ESD in cohort studies with pooled risk differences of 0.05 (CI, 0.03-0.07, I2 = 34%) and 0.14 (CI, 0.04-0.24, I2 = 83%). However, comparison of en bloc/R0 resection rate between two surgery strategies could not be estimated in RCT. Pooled results in cohort studies and data from RCT revealed comparable occurrence rate of adverse events between PCM-ESD and C-ESD. Measurements and outcomes of operation time/speed varied between the included studies and no consistent conclusion could be achieved in this aspect. The results indicate that PCM-ESD is an effective and well-tolerated treatment for colorectal neoplasm lesions and may be a superior treatment to C-ESD in en bloc/R0 resection rate.

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.

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.

Endoscopic Submucosal Dissection in North America: A Large Prospective Multicenter Study

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) in Asia has been shown to be superior to endoscopic mucosal resection (EMR) and surgery for the management of selected early gastrointestinal cancers. We aimed to evaluate technical outcomes of ESD in North America.

METHODS

We conducted a multicenter prospective study on ESD across 10 centers in the United States and Canada between April 2016 and April 2020. End points included rates of en bloc resection, R0 resection, curative resection, adverse events, factors associated with failed resection, and recurrence post-R0 resection.

RESULTS

Six hundred and ninety-two patients (median age, 66 years; 57.8% were men) underwent ESD (median lesion size, 40 mm; interquartile range, 25-52 mm) for lesions in the esophagus (n = 181), stomach (n = 101), duodenum (n = 11), colon (n = 211) and rectum (n = 188). En bloc, R0, and curative resection rates were 91.5%, 84.2%, and 78.3%, respectively. Bleeding and perforation were reported in 2.3% and 2.9% of the cases, respectively. Only 1 patient (0.14%) required surgery for adverse events. On multivariable analysis, severe submucosal fibrosis was associated with failed en bloc, R0, and curative resection and higher risk for adverse events. Overall recurrence was 5.8% (31 of 532) at a mean follow-up of 13.3 months (range, 1-60 months).

CONCLUSIONS

In this large multicenter prospective North American experience, we demonstrate that ESD can be performed safely, effectively, and is associated with a low recurrence rate. The technical resection outcomes achieved in this study are in line with the current established consensus quality parameters and further support the implementation of ESD for the treatment of select gastrointestinal neoplasms; ClinicalTrials.gov, Number: NCT02989818.

Comparison of dissection speed during colorectal ESD between the novel Multiloop (M-loop) traction method and ESD methods without traction

Background and study aims  We previously reported on a novel traction method called Multiloop (M-loop) for faster colorectal endoscopic submucosal dissection (ESD). In this study, we retrospectively compared the difference in submucosal dissection time (SDT), and submucosal dissection speed (SDS) between groups of patients who were treated using traction with the M-loop method, and with non-traction methods of colorectal ESD. Patients and methods  We reviewed and timed duration of colorectal ESD by the non-traction method from videos recorded between June 2016 and December 2017. From January 2018 onward, we used the M-loop method during all colorectal ESDs and timed it until August 2018. Outcomes of colorectal ESD with the M-loop method and non-traction methods were compared. The study involved two experts and eight non-experts and was carried out at a tertiary endoscopic center in Japan. Results  The study included 50 patients who treated with the M-loop method and 115 patients treated with the non-traction method. Submucosal dissection time (SDT) was not significantly different (M-loop group, 42.1  ±  4.2 min, non-traction ESD group, 51.9 ± 3.3 min) ( P  = 0.098), but submucosal dissection speed (SDS) was significantly greater (M-loop group, 28.0 ± 2.9 mm ²  /min, non-traction ESD group, 19.9 ± 2.0 mm ² /min) ( P  = 0.0014) in the M-loop method group. Multivariate analysis showed that the M-loop method increased SDS by odds ratio of 1.46 ( P  = 0.001) when compared to the non-traction ESD method. A significant difference was also observed for SDT and SDS when the two methods were compared after propensity score matching ( P  = 0.001). No differences in unfavorable outcomes were observed. Conclusions  The M-loop method improved SDS compared to non-traction methods of ESD. The method is an effective tool to assist colorectal ESD.

Review on colorectal endoscopic submucosal dissection focusing on the technical aspect

BACKGROUND

Endoscopic submucosal dissection (ESD) enables removal of broad-based colorectal polyps or lateral spreading tumors with a higher rate of en bloc resection and a lower risk of local recurrence. However, it is technically demanding. Over the past 20 years, various equipment and innovative techniques have been developed to reduce the difficulty of ESD. The information in the literature is scattered. Our aim is to provide a comprehensive review on the setup and technical aspects of colorectal ESD.

METHODS

We searched the PubMed database and systemically reviewed all original and review articles related to colorectal ESD. Further manual search according to reference lists of identified articles were done. The selected articles were categorized and reviewed. Original figures were created to help readers understand some of the ESD techniques.

RESULTS

A total of 216 articles were identified, in which 25 of them were review articles and 191 of them were original articles. They were categorized and reviewed. An in-depth appraisal of the setting, equipment, and technical aspects of colorectal ESD was performed.

CONCLUSIONS

Although ESD is a technically demanding procedure that requires expert endoscopic skills, it can be mastered. With good peri-procedural preparation, sufficient knowledge of the equipment, and thorough understanding of the useful endoscopic tricks and maneuvers, colorectal ESD can be performed smoothly and safely.

Endoscopic submucosal dissection in rectal tumors extending or not to the dentate line: A comparative analysis

BACKGROUND

The feasibility of endoscopic submucosal dissection (ESD) in rectal tumors extending to the dentate line (RTDL) is unclear.

AIMS

To analyze the outcomes of ESD in RTDL compared to non-RTDL, with a special focus on the lower rectum location.

METHODS

Observational multicenter retrospective study. All patients with a rectal tumor who underwent ESD in 2013-2017 were included. A comparative analysis between RTDL and non-RTDL groups was done.

RESULTS

Two-hundred and twenty-eight patients (median age: 69 years, range: 33-89, 51.3% male) with RTDL (n = 65, 28.5%) and non-RTDL lesions (n = 163, 71.5%) were included. There were no significant differences between the en-bloc (89.2% vs. 90.8%, p = 0.718), complete (60% vs. 71.8%, p = 0.084) and curative resection rates (58.5% vs. 68.7%, p = 0.141). The overall complication rate (4.6% vs. 8%, p = 0.370) was not different, independently of the rectal location. Local recurrence was higher in RTDL (7.3% vs. 1.5%, p = 0.065). The indication for surgery due to non-curative resections in the lower rectum was lower in RTDL (9.2% vs. 14.6%, p = 0.378).

CONCLUSION

The safety, effectiveness and long-term impact of ESD in RTDL and non-RTDLs is comparable. Local recurrence in the lower rectum may be higher in RTDL.

Salvage endoscopic submucosal dissection for incompletely resected esophageal or gastric neoplasms (case series)

Background and study aims  Given that positive lateral margins indicate possible residual carcinoma, salvage endoscopic submucosal dissection (ESD) should be considered for curative therapy. Presence of submucosal fibrosis, however, makes the procedure difficult to perform. We present our case series to discuss the feasibility of salvage ESD and the timing of the procedure.

Safety and efficacy of endoscopic submucosal dissection for rectal neoplasia: a multicenter North American experience

Background and aims  Rectal lesions traditionally represent the first lesions approached during endoscopic submucosal dissection (ESD) training in the West. We evaluated the safety and efficacy of rectal ESD in North America. Methods  This is a multicenter retrospective analysis of rectal ESD between January 2010 and September 2018 in 15 centers. End points included: rates of en bloc resection, R0 resection, adverse events, comparison of pre- and post-ESD histology, and factors associated with failed resection. Results  In total, 171 patients (median age 63 years; 56 % men) underwent rectal ESD (median size 43 mm). En bloc resection was achieved in 141 cases (82.5 %; 95 %CI 76.8-88.2), including 24 of 27 (88.9 %) with prior failed endoscopic mucosal resection (EMR). R0 resection rate was 74.9 % (95 %CI 68.4-81.4). Post-ESD bleeding and perforation occurred in 4 (2.3 %) and 7 (4.1 %), respectively. Covert submucosal invasive cancer (SMIC) was identified in 8.6 % of post-ESD specimens. There was one case (1/120; 0.8 %) of recurrence at a median follow-up of 31 weeks; IQR: 19-76 weeks). Older age and higher body mass index (BMI) were predictors of failed R0 resection, whereas submucosal fibrosis was associated with a higher likelihood of both failed en bloc and R0 resection. Conclusion  Rectal ESD in North America is safe and is associated with high en bloc and R0 resection rates. The presence of submucosal fibrosis was the main predictor of failed en bloc and R0 resection. ESD can be considered for select rectal lesions, and serves not only to establish a definitive tissue diagnosis but also to provide curative resection for lesions with covert advanced disease.

Preoperative endoscopic predictors of severe submucosal fibrosis in colorectal tumors undergoing endoscopic submucosal dissection

Background and study aims  Endoscopic submucosal dissection (ESD) enables en bloc removal of colorectal neoplasms regardless of size. Submucosal fibrosis is a significant factor for technical difficulty and poor outcomes. We assessed the predictive factors for severe submucosal fibrosis and the ESD outcomes. Patients and methods  Patients undergoing ESD from January 2006 to September 2017 were retrospectively reviewed. The degree of submucosal fibrosis was classified into three types: no fibrosis (F0), mild fibrosis (F1), and severe fibrosis (F2). F0 and F1 cases were grouped as non-severe fibrosis for comparison with the severe fibrosis group. Predictors of severe submucosal fibrosis and ESD outcomes were evaluated. Results  ESD was performed in 524 lesions (60 % male; mean age, 67.8 years). Eighty lesions with severe fibrosis (15.3 %) were observed. The overall en bloc resection rate and curative resection rate were 94.3 % and 77.7 %, respectively. Rates of en bloc resection (91.2 % vs. 94.8 %, P  = 0.2) and perforation (7.5 % vs. 5.6 %, P  = 0.45) were no different between severe fibrosis and non-severe fibrosis groups. However, incidences of non-curative resection and low resection speed were significantly higher in the severe fibrosis group. Among protruding lesions, tumor height and volume were significantly greater in the severe counterparts. A diameter ≥ 40 mm, endoscopic finding of the tumor beyond fold, and fold convergence were independent risk factors for severe fibrosis. Conclusions  Severe submucosal fibrosis is a significant risk factor for non-curative resection and a long procedural time. Tumor size and morphology might help to predict the severity of fibrosis.

Factors Predictive of Complete Excision of Large Colorectal Neoplasia Using Hybrid Endoscopic Submucosal Dissection: A KASID Multicenter Study

BACKGROUND

Endoscopic submucosal dissection (ESD) with snaring (hybrid ESD) bridges the gap between ESD and endoscopic mucosal resection. We evaluated factors predictive of en bloc and complete resection of large colorectal neoplasms using hybrid ESD.

METHODS

This was a prospective clinical study of 78 patients who underwent hybrid ESD for excision of colorectal neoplasms (≥ 2 cm) between May 2015 and September 2016 at six university hospitals. We evaluated lesion and patient characteristics, endoscopist experience level (< 50 or ≥ 50 cases with colorectal ESD), and technical factors such as concurrent fibrosis, completion of a circumferential incision, degree of submucosal dissection (< 50 or ≥ 50%), and visualization during snaring (< 50 or ≥ 50%).

RESULTS

Multivariate analyses showed that the en bloc resection rate was significantly related to the degree of visualization during snaring (odds ratio (OR) 7.811, 95% confidence interval [CI] 1.722-35.426; p = 0.008) and the presence of fibrosis (OR 0.258, 95% CI 0.68-0.993; p = 0.049). The complete resection rate was significantly related to the colorectal ESD endoscopist skill level (OR 5.626, 95% CI 1.485-21.313; p = 0.011) and gross lesion type (OR 0.145, 95% CI 0.022-0.936; p = 0.042). When all three technical factors, i.e., completion of circumferential incision, ≥ 50% submucosal dissection, and ≥ 50% visualization during snaring, were satisfied performing hybrid ESD, the en bloc resection rate (87.5%) was similar to that of ESD.

CONCLUSIONS

Visualization during snaring, presence of fibrosis, gross lesion type, and endoscopist colorectal ESD experience level affect en bloc or complete resection of large colorectal neoplasia using hybrid ESD.

Perforation and Postoperative Bleeding Associated with Endoscopic Submucosal Dissection in Colorectal Tumors: An Analysis of 398 Lesions Treated in Saga, Japan

Objective The aim of this study was to clarify the safety of colorectal endoscopic submucosal dissection (ESD) during the era of health insurance coverage starting from April 2012 in Japan. Methods Between April 2012 and May 2016, ESD was applied to 398 lesions in 373 patients. Risk factors for serious complications of colorectal ESD, perforation and post-ESD bleeding, were evaluated focusing on the resected specimen size, location, growth pattern, invasion depth, histopathology, postoperative clipping, and procedure time. In addition, the relationship between serious complications and patients' background characteristics was analyzed. Results Among 373 patients, perforation occurred in 12 patients and post-ESD bleeding in 19 patients. A univariate analysis showed that the risk factors for perforation were the lesion size, the resected specimen size, and a long operation time. A multivariate analysis showed that a long operation time was a risk factor for perforation during colorectal ESD. A univariate analysis indicated that significant risk factors for postoperative bleeding were a long operation time, rectal lesion, and cancer. All patients with serious complications were treated by an endoscopic procedure without blood transfusion or the need to convert to open surgery. Conclusion The present study suggests that colorectal ESD may be accepted with relative safety in Japan as a common therapeutic approach for early colorectal cancer.

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

BACKGROUND AND STUDY AIMS

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Local recurrence and subsequent endoscopic treatment after endoscopic piecemeal mucosal resection with or without precutting in the colorectum

Background/Aims

Precutting before endoscopic piecemeal mucosal resection (EPMR) may increase colorectal polyp resection effectiveness. We aimed to identify risk factors for recurrence after conventional EPMR (CEPMR) and precut EPMR (PEPMR) and investigated endoscopic treatment outcomes for recurrent cases.

Methods

The medical records of patients with colorectal polyps treated by EPMR were analyzed. Patients without follow-up surveillance colonoscopies were excluded.

Results

Among 359 lesions, the local recurrence rate on the first surveillance colonoscopy was 5.8% (18/312) and 6.4% (3/47) after CEPMR and PEPMR, respectively. Among lesions without recurrence at the first surveillance colonoscopy, the rates of late recurrence on subsequent surveillance colonoscopy were 3.9% (6/152) and 0% after CEPMR and PEPMR, respectively. Larger tumor size was the only independent risk factor for recurrence (odds ratio, 7.93; 95% confidence interval, 1.95–32.30; P<0.001). Endoscopic treatment was performed for all 27 recurrences. A combination of ≥2 endoscopic treatment modalities was used in 19 of 27 recurrences (70.4%). Surveillance colonoscopies were performed in 20 of 27 recurrences after endoscopic treatment. One (5.0%) had a re-recurrence and was treated by surgical resection because recurrence occurred at the appendiceal orifice. Nineteen of 20 lesions (95.0%) could be cured endoscopically, although 3 of the 19 showed second or third recurrences and were treated by repeat endoscopic resection.

Conclusions

The local recurrence rates after CEPMR and PEPMR were similar. Larger tumor size was an independent risk factor for local recurrence after EPMR. Endoscopic treatment of recurrences resulted in high cure rates, although combination methods were necessary in many cases.