Retrospective study of technical aspects and complications of endoscopic submucosal dissection for laterally spreading tumors of the colorectum

Efficacy of water pressure method for colorectal endoscopic submucosal dissection: Propensity-score matching analysis

Background and study aims

Technical difficulty of endoscopic submucosal dissection (ESD) for colorectal neoplasms has not been resolved. The water pressure method (WPM) is a helpful technique for overcome difficulties with colorectal ESD. We evaluated the efficacy and safety of ESD with WPM (WPM-ESD) for colorectal neoplasms compared with conventional ESD (C-ESD).

Patients and methods

This was a single-center, retrospective, observational study. Three hundred and eleven colorectal lesions were allocated into the WPM-ESD and the C-ESD groups, which were compared before and after propensity score matching. The main outcomes were procedure time, proportion of R0 resection, and incidence of adverse events (AEs) in the two groups.

Results

The WPM-ESD and C-ESD groups were allocated 134 and 177 lesions, respectively, and propensity score matching analysis created 92 matched pairs. Mean procedure time was significantly shorter in the WPM-ESD group (49 ± 26 vs. 58 ± 42 min, P = 0.032). All lesions were resected in one piece and there was no difference in the proportion of en bloc resection (100% vs. 100%) and R0 resection (92% vs. 96%, P = 0.536) or in incidence of intraoperative perforation (2.2% vs. 2.2%) in the two groups.

Conclusions

WPM for colorectal ESD may shorten procedure time compared with C-ESD without increasing AEs.

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.

Long-term outcomes of endoscopic submucosal dissection for T1b colorectal cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) is a standardized procedure for intramucosal and slightly invasive submucosal colorectal cancers (CRC). However, the role of ESD for T1b (depth of submucosal invasion: ≥1,000 μm) CRC remains unclear. This study aimed to investigate the long-term efficacy and safety of ESD for T1b CRC.

METHODS

This study involved 50 patients with T1b CRC who underwent ESD, including 31 who received subsequent surgery (ESD + surgery group) and 19 who reported comorbidities or refused subsequent surgery (ESD-alone group). The clinical outcomes, lymph node metastasis (LNM) rate, and recurrence and survival rates were determined.

RESULTS

All the patients achieved en-bloc resection, and 41 patients achieved R0 resection. The mean tumor diameter was 31.2 ± 11.9 mm. LNM was detected in 3 (6%) cases, demonstrating high-grade tumor budding (Bd 2/3) and invasion depth of >1,500 um. LNM was significantly correlated with tumor budding (P = 0.030). The overall median follow-up period was 41.00 ± 27.69 months and 33.16 ± 19.05 months in the ESD-alone and ESD + surgery groups, respectively (P = 0.241). Two patients in the ESD group had local recurrence and two patients died. Patients in the ESD + surgery group reported no local recurrence, distant metastasis, or disease-related death. Recurrence (P = 0.074) and survival rates (P = 0.072) were not significantly different between the two groups.

CONCLUSIONS

The LNM rate was exceedingly low in patients with T1b. ESD is an effective and safe method for these patients. The necessity of additional surgical treatment after ESD should be comprehensively determined following the patient's characteristics.

Submucosal injection fluid and tattoo agents

BACKGROUND AND AIMS

EMR and endoscopic submucosal dissection (ESD) are minimally invasive endoscopic techniques, developed for the removal of benign and early malignant lesions throughout the GI tract. Submucosal injection of a marking agent can help to identify lesions during surgery. Endoscopic resection frequently involves "lifting" of the lesions by injection of a substance within the submucosal space to create a cushion for safe resection. This review summarizes the current techniques and agents available for endoscopic marking and lifting of GI tract lesions.

METHODS

The MEDLINE database was searched through April 2023 for relevant articles related to the lifting and marking aspect of EMR by using key words such as "endoscopy" or "endoscopic" combined with "marking," "tattoo," and "lifting." The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy.

RESULTS

This technology review describes the techniques for endoscopic tattoo placement and submucosal lifting, along with currently available agents, safety, and costs.

CONCLUSIONS

Endoscopists performing EMR and ESD have several choices in submucosal injection materials for lifting and marking agents for tattoos. These may be commercially prepared agents or off-the-shelf materials with or without additives to facilitate visualization. A thorough understanding of the indications, techniques, properties of various agents, costs, and adverse events is necessary in choosing the appropriate materials and technique to optimize lesion resection in EMR and ESD.

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.

Clinical outcomes of colorectal neoplasm with positive resection margin after endoscopic submucosal dissection

A positive resection margin after colorectal endoscopic submucosal dissection (ESD) is associated with an increased risk of recurrence. We aimed to identify the clinical significance of positive resection margins in colorectal neoplasms after ESD. We reviewed 632 patients who had en bloc colorectal ESD at two hospitals between 2015 and 2020. The recurrence rates and presence of residual tumor after surgery were evaluated. The rate of additional surgery after ESD and recurrence rate were significantly higher in patients with incomplete resection (n = 75) compared to patients with complete resection (n = 557). When focusing solely on non-invasive lesions, no significant differences in recurrence rates were observed between the groups with complete and incomplete resection (0.2% vs. 1.9%, p = 0.057). Among 84 patients with submucosal invasive carcinoma, 39 patients underwent additional surgery due to non-curative resection. Positive vertical margin and lymphovascular invasion were associated with residual tumor. Lymphovascular invasion was associated with lymph node metastasis. However, no residual tumor nor lymph node metastases were found in patients with only one unfavorable histological factor. In conclusion, a positive resection margin in non-invasive colorectal lesions, did not significantly impact the recurrence rate. Also, in T1 colorectal cancer with a positive vertical resection margin, salvage surgery can be considered in selected patients with additional risk factors.

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.

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

Objectives

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

Methods

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

Results

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

Conclusions

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

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

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Experimental study of magnetic hydrogel assisted magnetic anchorguided endoscopic submucosal dissection in colonic tumors

BACKGROUND

Endoscopic submucosal dissection (ESD) is a well-established treatment for gastrointestinal tumors and enables en bloc resection. Adequate counter traction with good visualization is important for safe and effective dissection.

OBJECTIVE

Based on magnetic anchor-guided endoscopic submucosal dissection (MAG-ESD), we would like to explore the feasibility of magnetic hydrogel as an internal magnetic anchor that can be injected into the submucosa through an endoscopic needle to assist colonic endoscopic submucosal dissection.

METHODS

This prospective trial was conducted on 20 porcine colons ex vivo. We injected magnetic hydrogel into submucosa of the porcine colons ex vivo for MAG-ESD to evaluate the traction effect and operation satisfaction.

RESULTS

Magnetic hydrogel assisted ESD was successfully performed on 20 porcine colons ex vivo. Adequate counter traction with good visualization was successfully obtained during the procedure of dissection.

CONCLUSION

Magnetic hydrogel assisted MAG-ESD is feasible and effective.

Endoscopic full-thickness resection versus endoscopic submucosal dissection for challenging colorectal lesions: a randomized trial

BACKGROUND AND AIMS

The optimal endoscopic resection method of challenging colorectal lesions (ie, adenomatous recurrences, nongranular laterally spreading tumors [LST-NGs], lesions without lifting sign <30 mm) is still under debate. The aim of this study was to directly compare endoscopic submucosal dissection (ESD) and endoscopic full-thickness resection (EFTR) for the resection of challenging colorectal lesions in a randomized trial.

METHODS

A multicenter, prospective, randomized study was performed in 4 Italian referral centers. Consecutive patients referred for endoscopic resection of challenging lesions were randomly assigned to undergo EFTR or ESD. Primary outcomes were complete (R0) resection and en bloc resection of lesions. Technical success, procedure time, procedure speed, area of the resected specimen, adverse event rate, and local recurrence rate at 6 months were also compared.

RESULTS

Overall, 90 patients were included in the study, equally representing the 3 challenging lesion types. Age and sex were comparable in the 2 groups. En bloc resection was obtained in 95.5% of the EFTR group and in 93.3% of the ESD group. R0 resection rate was comparable in the 2 groups (EFTR vs ESD, 42 [93.3%] vs 36 [80%]; P = .06). The EFTR group exhibited a significantly shorter total procedure time (25.6 ± 10.6 minutes vs 76.7 ± 26.4 minutes, P ≤ .01), as well as overall procedure speed (16.8 ± 11.8 mm2/min vs 11.9 ± 9.2 mm2/min, P = .03). The EFTR group had a significantly smaller mean lesion size (21.6 ± 8.3 mm vs 28.7 ± 7.7 mm, P ≤ .01). Adverse events were reported less frequently in patients in the EFTR group (4.44% vs 15.5%, P = .04).

CONCLUSIONS

EFTR is comparable to ESD in the treatment of challenging colorectal lesions in terms of safety and efficacy. EFTR is considerably faster than ESD in the treatment of nonlifting lesions and adenoma recurrences. (Clinical trial registration number: NCT05502276.).

Endoscopic Submucosal Dissection of Superficial Colorectal Neoplasms at "Challenging Sites" Using a Double-Balloon Endoluminal Interventional Platform: A Single-Center Study

BACKGROUND

Colonic endoscopic submucosal dissection (ESD) at "challenging sites" such as the cecum, ascending colon, and colonic flexures could be difficult even for expert endoscopists due to poor endoscope stability/maneuverability, steep angles, and thinner wall thickness. A double-balloon endoluminal intervention platform (EIP) has been introduced in the market to fasten and facilitate ESD, particularly when located at difficult sites. Here, we report our initial experience with an EIP comparing the outcomes of an EIP versus standard ESD (S-ESD) at "challenging sites".

MATERIALS AND METHODS

We retrospectively collected data on consecutive patients with colonic lesions located in the right colon and at flexures who underwent ESD in our tertiary referral center between March 2019 and May 2023. Endoscopic and clinical outcomes (technical success, en bloc resection rate, R0 resection rate, procedure time, time to reach the lesion, and adverse events) and 6-month follow-up outcomes were analyzed.

RESULTS

Overall, 139 consecutive patients with lesions located at these challenging sites were enrolled (EIP: 31 and S-ESD: 108). Demographic characteristics did not differ between groups. En bloc resection was achieved in 92.3% and 93.5% of patients, respectively, in the EIP and S-ESD groups. Both groups showed a comparable R0 resection rate (EIP vs. S-ESD: 92.3% vs. 97.2%). In patients undergoing EIP-assisted ESD, the total procedure time was shorter (96.1 [30.6] vs. 113.6 [42.3] minutes, p = 0.01), and the mean size of the resected lesions was smaller (46.2 ± 12.7 vs. 55.7 ± 17.6 mm, p = 0.003). The time to reach the lesion was significantly shorter in the EIP group (1.9 ± 0.3 vs. 8.2 ± 2.7 min, p ≤ 0.01). Procedure speed was comparable between groups (14.9 vs. 16.6 mm2/min, p = 0.29). Lower adverse events were observed in the EIP patients (3.8 vs. 10.2%, p = 0.31).

CONCLUSIONS

EIP allows results that do not differ from S-ESD in the resection of colorectal superficial neoplasms localized in "challenging sites" in terms of efficacy and safety. EIP reduces the time to reach the lesions and may more safely facilitate endoscopic resection.

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.

Usefulness of a new polyvinyl alcohol hydrogel (PVA-H)-based simulator for endoscopic submucosal dissection training: a pilot study

BACKGROUND/AIMS

We developed a new endoscopic submucosal dissection (ESD) simulator and evaluated its efficacy and realism for use training endoscopists.

METHODS

An ESD simulator was constructed using polyvinyl alcohol hydrogel sheets and compared to a previous ESD simulator. Between March 1, 2020, and December 30, 2021, eight expert endoscopists from three different centers analyzed the procedure-related factors of the simulator. Five trainees performed gastric ESD exercises under the guidance of these experts.

RESULTS

Although the two ESD simulators provided overall favorable outcomes in terms of ESD-related factors, the new simulator had several benefits, including better marking of the target lesion's limits (p<0.001) and overall handling (p<0.001). Trainees tested the usefulness of the new ESD simulator. The complete resection rate improved after 3 ESD training sessions (9 procedures), and the perforation rate decreased after 4 sessions (12 procedures).

CONCLUSION

We have developed a new ESD simulator that can help beginners achieve a high level of technical experience before performing real-time ESD procedures in patients.

First pilot trial of colorectal ESD guided by a new magnetic anchor for ease of placement

BACKGROUND

In recent years, studies have demonstrated that magnetic anchor-guided endoscopic submucosal dissection (MAG-ESD) is feasible and safe and may facilitate the treatment of all difficult lesions. However, the major problem with MAG-ESD is the inability to deliver the magnetic anchor to the gastrointestinal tract without withdrawal or reinsertion of the endoscope. Therefore, our team developed a magnetic anchor that could be easily inserted through the biopsy channel, facilitating ESD traction and evaluated its effectiveness and safety.

METHODS

The study was conducted between October 2020 and June 2021 at The Second Affiliated Hospital of Harbin Medical University, China. One hundred and twelve patients with colorectal tumors treated with ESD were divided into two groups for historical control comparison. A channel-placed magnetic anchor (CPMAG) group and a control group consisting of patients who had conventional ESD without adjuvant traction. The rate of en bloc resection and resection with tumor-free lateral/basal margins (R0 resection), dissection speeds, procedure time, intraoperative bleeding and perforation complications, and postoperative follow-up were compared between the two groups, so as to evaluate the clinical effect and safety of the new magnetic anchor.

RESULTS

The en bloc resection and R0 resection rate with CPMAG-ESD were slightly higher than with conventional ESD but this was not statistically significant. The median dissection speeds with CPMAG-ESD were higher than with conventional ESD, but the difference was not statistically significant. Intraoperative bleeding and postoperative complications with the CPMAG-ESD were less than with conventional ESD, but this was not statistically significant. The median operating time was shorter with CPMAG- ESD than with conventional ESD (24.5 min [range 15.8-66.5 min] vs 39 min [range 29-58 min], p = 0.024), and this difference was statistically significant.

CONCLUSIONS

The new magnetic anchor-guided ESD technique appears to be a feasible and safe method for treating early colorectal tumors with en bloc resection, with improvement of the submucosal visual field, and less adverse events.

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

Background

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

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

Methods

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

Results

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

Conclusions

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

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.

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.

Risk factors of delayed post-polypectomy bleeding after treatment of gastrointestinal polyps with snare-assisted endoscopic sub-mucosal dissection

Context

Gastrointestinal polyps are common gastrointestinal diseases that involve localised hyperplastic masses derived from gastrointestinal mucosa.

Aims

To investigate the risk factors of delayed post-polypectomy bleeding (DPPB) after the treatment of gastrointestinal polyps with snare-assisted endoscopic sub-mucosal dissection (ESD) and to construct a nomogram model to predict the risk of DPPB.

Settings and Design

A total of 226 patients who underwent snare-assisted ESD for gastrointestinal polyps from May 2018 to November 2020 were divided into DPPB group (n = 10) and non-DPPB group (n = 216).

Subjects and Methods

The correlations of clinical data and endoscopic data with DPPB were compared. Univariate analysis was performed to screen the influencing factors of DPPB. Multivariate logistic regression analysis was used to screen the risk factors of DPPB, which was employed to construct a nomogram prediction model.

Statistical Analysis Used

SPSS 16.0 software was utilised for statistical analysis. Numerical data were expressed as percentage (n [%]), and Chi-square test was performed for univariate analysis. The significant factors (P < 0.05) in univariate analysis were included in multivariate logistic regression analysis, and the variables with statistical significance (P < 0.05) were considered as independent risk factors. The factors were used to construct a nomogram model for predicting the risk of DPPB. Bootstrap method was employed to perform repeated sampling 1000 times for internal verification. The consistency index (C-index) was used to evaluate the discrimination of the model, and C-index ≥0.70 represented a good discrimination. Two-tailed P < 0.05 indicated that a difference was statistically significant.

Results

Univariate and multivariate logistic regression analyses revealed that hypertension, polyp location, polyp diameter, polyp morphology and intra-operative bleeding were the independent risk factors for DPPB (P < 0.05). The C-index of the nomogram model for predicting the risk of DPPB was 0.791, indicating a good discrimination. The calibration curve showed that the mean absolute error between predicted and actual DPPB occurrence risks was 0.014, indicating a high accuracy.

Conclusions

Hypertension, polyp location, polyp diameter, polyp morphology and intra-operative bleeding are the independent risk factors for DPPB, and the nomogram model established based on these factors for prediction has good discrimination and accuracy. Therefore, it is recommended to perform targeted intervention for high-risk groups to reduce the incidence of DPPB.

Timing of pyloric stenosis and effectiveness of endoscopic balloon dilation after pyloric endoscopic submucosal dissection

BACKGROUND AND AIM

There have been studies on risk factors for stenosis after pyloric endoscopic submucosal dissection (ESD). However, the most appropriate strategies for the management of cases with these risk factors have not been established. This study aimed to investigate post-ESD management by evaluating the timing of stenosis and the effectiveness of endoscopic balloon dilation (EBD) after pyloric ESD.

METHODS

We retrospectively reviewed cases of pyloric ESD. We first reassessed risk factors for stenosis in multivariate analysis and receiver operating characteristic curve and defined patients with the identified risk factors as the risk group. The primary outcome was the timing of stenosis in the risk group assessed by the Kaplan-Meier method.

RESULTS

We reviewed 159 cases with pyloric ESD and observed pyloric stenosis in 25 cases. Cases with circumferential mucosal defect ≥ 76% were identified as the risk group. The stenosis-free probability in the risk group was 97% (95% confidence interval [CI]: 79-100%), 94% (95% CI: 76-98%), and 85% (95% CI: 66-93%) on days 7, 14, and 21, respectively. It decreased every week thereafter and did not significantly change after day 56. Twenty-three stenosis cases, except for conservative improvement, including six whole circumferential pyloric ESD cases, were improved by EBD without complications.

CONCLUSIONS

Post-ESD stenosis often developed from the third to the eighth week. In all pyloric ESD cases, including whole circumferential pyloric ESD cases, pyloric stenosis was improved following EBD without complications.

A retrospective cohort study of factors influencing long procedure times in colorectal endoscopic submucosal dissection

OBJECTIVE

To evaluate the outcomes and factors influencing colorectal endoscopic submucosal dissection (ESD) with a long procedure time.

MATERIALS AND METHODS

In this single-center, retrospective study, we included 1,100 patients with 1,199 lesions who underwent colorectal ESD between April 2016 and December 2020. ESD was performed using an advanced system knife for lesions >20 mm. An S-O clip was used as the traction device. The long-time group (LP; procedure time >120 min) and normal-time group (NP; procedure time <120 min) were compared.

RESULTS

The procedure times were 166.86 and 44.72 min in the LP and NP groups, respectively. The completion rate was higher in the NP group (96.5% vs. 83.5%, p = .001); the completed lesions were resected en bloc. Multivariate analysis revealed 18.8% and 7.8% of submucosal fibrosis in the LP and NP groups, respectively (odds ratio [OR] = 2.410, p = .026). Compared to the NP group, the LP group presented larger maximum lesion sizes and higher rates of R1 resection, and traction device use. Time to introduction of traction device use was longer in the LP than in the NP group (126.05 vs. 21.72 min; p < .001). Fibrosis tends to occur cecal lesions (OR 2.436, p = .011) and laterally spreading tumor-non-granular-pseudo-depressed (LST-NG-PD) (OR 2.6181, p = .001).

CONCLUSIONS

Lesion size and fibrosis were factors associated with a long procedure time in colonic ESD. For fibrotic lesions (LST-NG-PD and cecal lesions), it is necessary to consider early use of traction devices and advisable to plan a strategy for the use of traction devices.

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

Background

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

Methods

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

Results

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

Conclusions

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

Colorectal Endoscopic Submucosal Dissection: An Update on Best Practice

Endoscopic submucosal dissection (ESD) is a method of en-bloc resection of neoplastic colorectal lesions which is less invasive compared to surgical resection. Lesion stratification, architecture recognition and estimation of depth of invasion are crucial for patient selection. Expert endoscopists have integrated a variety of classification systems including Paris, lateral spreading tumor (LST), narrow band imaging (NBI), international colorectal endoscopic (NICE) and Japanese NBI expert team (JNET) in their day-to-day practice to enhance lesion detection accuracy. Major societies recommend ESD for LST-non granular (NG), Kudo-VI type, large depressed and protruded colonic lesions with shallow submucosal invasion. Chance of submucosal invasion enhances with increased depth as well as tumor location and size. In comparison to endoscopic mucosal resection (EMR), ESD has a lowerl recurrence rate and higher curative resection rate, making it superior for larger colonic lesions management. Major complications such as bleeding and perforation could be seen in up to 11% and 16% of patients, respectively. In major Western countries, performing ESD is challenging due to limited number of expert providers, lack of insurance coverage, and unique patient characteristics such as higher BMI and higher percentage of previously manipulated lesions.

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.

Factors influencing interruption of colorectal endoscopic submucosal dissection

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.).

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.

Long-term outcomes of endoscopic treatment for colorectal laterally spreading tumor: a large-scale multicenter retrospective study from China

BACKGROUND

Laterally spreading tumor (LST) is a type of precancerous lesion of colorectal cancer with high malignant potential. The present study aimed to evaluate long-term outcomes of endoscopic treatment for LST in Chinese patients.

METHODS

This study was a retrospective review of data collected from 653 included patients with LST from six regional representative hospitals in China between January 2007 and January 2017. Demographic characteristics, endoscopic features of LST, operation-related data, and follow-up results were collected and analyzed.

RESULTS

LST-granular type (LST-G, 80.3%) was much more common than LST-non-grandular type (LST-NG, 19.7%). The overall submucosal invasion rate of all LSTs was 6.1% and the submucosal invasion rate of LST-NG was significantly higher than that of LST-G (6.79% vs. 3.87%, p = 0.000). The en bloc resection rate of ESD and EMR treatment was 96% and 93.7%, respectively, with pathologic R0 resection rate of 90.1% and 82.8%. After an average duration of follow-up about 34.52 ± 11.76 months, the recurrence rate of ESD was 3.47%, and the recurrence rate of EMR was 8.8% after an average follow-up of about 38.44 ± 4.42 months. However, the recurrence rate of ESD was much lower than piecemeal EMR for LST (3.47% vs. 8.62%, p = 0.017). Retroflexion-assisted technique applied for resection of rectal LST was associated with a significantly shortened operating time (85.40 min vs. 174.18 min, p = 0.002).

CONCLUSION

Endoscopic resection is a safe and efficient modality for the treatment of colorectal LST with a relatively low recurrence rate and shortened operating time with the use of retroflexion.

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

BACKGROUND AND STUDY AIMS

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

ASGE review of adverse events in colonoscopy

Colonoscopy is the most commonly performed endoscopic procedure and overall is considered a low-risk procedure. However, adverse events (AEs) related to this routinely performed procedure for screening, diagnostic, or therapeutic purposes are an important clinical consideration. The purpose of this document from the American Society for Gastrointestinal Endoscopy's Standards of Practice Committee is to provide an update on estimates of AEs related to colonoscopy in an evidence-based fashion. A systematic review and meta-analysis of population-based studies was conducted for the 3 most common and important serious AEs (bleeding, perforation, and mortality). In addition, this document includes an updated systematic review and meta-analysis of serious AEs (bleeding and perforation) related to EMR and endoscopic submucosal dissection for large colon polyps. Finally, a narrative review of other colonoscopy-related serious AEs and those related to specific colonic interventions is included.

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

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

Predictors of invasive cancer of large laterally spreading colorectal tumors: A multicenter study in Japan

Background and Aim

Although colorectal laterally spreading tumors (LSTs) can be classified into four subtypes, the histopathological characteristics are known to differ among these subtypes. We therefore performed a logistic regression analysis to determine whether the risk of pathological T1 cancer of large colorectal LSTs can be predicted based on factors such as endoscopic findings in a large group of patients enrolled in a multicenter study in Japan.

Methods

In the main study, we assessed 1236 colorectal adenomas or early cancers that were classified as LSTs measuring 20 mm or more in diameter and treated endoscopically. Logistic regression analysis was performed to determine whether factors such as the subtype of LST could be used to predict the risk of pathological T1 cancer. A validation study of 356 large colorectal LSTs was conducted to confirm the validity of the results obtained in the main study.

Results

The locations and tumor diameter of the LSTs in the main study were found to differ significantly according to the LST subclassification (P < 0.001). The frequency of pathological T1 cancers was the highest at 36% of LST nongranular pseudodepressed type, followed by 14% of LST nongranular flat‐elevated type, 11% of LST granular nodular mixed type, and 3% of LST granular homogenous type lesions. The risk of pathological T1 cancer was significantly associated with LST subclassification and tumor diameter. The area under the curve (AUC) was high (0.743). In the validation study, the AUC was 0.573.

Conclusions

In patients with large colorectal LSTs resected endoscopically, the risk of pathological T1 cancer can be predicted on the basis of the LST subclassification and tumor diameter.

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

BACKGROUND

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

METHODS AND MATERIALS

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

RESULTS

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

CONCLUSION

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

Clinical outcomes of colorectal endoscopic submucosal dissection and risk factors associated with piecemeal resection

BACKGROUND/AIMS

We aimed to investigate the factors associated with piecemeal resection of colorectal neoplasia (CRN), in spite of endoscopic submucosal dissection (ESD).

MATERIALS AND METHODS

We analyzed the retrospective data for colorectal ESD cases from January 2005 to April 2014. We also reviewed the piecemeal endoscopic mucosal resection (EMR) for CRNs ≥20 mm, performed over the same period.

RESULTS

En bloc resection was possible in 648 (85.7%) of 756 lesions in 740 patients. Multivariate analysis showed that hybrid ESD (odds ratio (OR), 29.07; 95% confidence interval (CI), 15.46-54.65; p<0.01) and mild or severe submucosal fibrosis (OR, 3.62; 95% CI, 1.94-6.76; p<0.01) were independently associated with piecemeal ESD. The en bloc ESD group showed higher histologic complete resection rate than the piecemeal ESD group (80.4% vs. 56.5%; p<0.01), and the piecemeal ESD group showed higher recurrence rate than in the en bloc ESD group (5.6% [4/72] vs. 0.7% [3/450]; p<0.01). Overall recurrence rate was 1.3% (7/522).

CONCLUSION

Hybrid ESD and submucosal fibrosis are independently associated with piecemeal ESD. Piecemeal ESD cases recurred more frequently than en bloc ESD cases.

Management of colorectal laterally spreading tumors: a systematic review and meta-analysis

Objective and study aims  To evaluate the efficacy and safety of different endoscopic resection techniques for laterally spreading colorectal tumors (LST). Methods  Relevant studies were identified in three electronic databases (PubMed, ISI and Cochrane Central Register). We considered all clinical studies in which colorectal LST were treated with endoscopic resection (endoscopic mucosal resection [EMR] and/or endoscopic submucosal dissection [ESD]) and/or transanal minimally invasive surgery (TEMS). Rates of en-bloc/piecemeal resection, complete endoscopic resection, R0 resection, curative resection, adverse events (AEs) or recurrence, were extracted. Study quality was assessed with the Newcastle-Ottawa Scale and a meta-analysis was performed using a random-effects model. Results  Forty-nine studies were included. Complete resection was similar between techniques (EMR 99.5 % [95 % CI 98.6 %-100 %] vs. ESD 97.9 % [95 % CI 96.1 - 99.2 %]), being curative in 1685/1895 (13 studies, pooled curative resection 90 %, 95 % CI 86.6 - 92.9 %, I ²  = 79 %) with non-significantly higher curative resection rates with ESD (93.6 %, 95 % CI 91.3 - 95.5 %, vs. 84 % 95 % CI 78.1 - 89.3 % with EMR). ESD was also associated with a significantly higher perforation risk (pooled incidence 5.9 %, 95 % CI 4.3 - 7.9 %, vs. EMR 1.2 %, 95 % CI 0.5 - 2.3 %) while bleeding was significantly more frequent with EMR (9.6 %, 95 % CI 6.5 - 13.2 %; vs. ESD 2.8 %, 95 % CI 1.9 - 4.0 %). Procedure-related mortality was 0.1 %. Recurrence occurred in 5.5 %, more often with EMR (12.6 %, 95 % CI 9.1 - 16.6 % vs. ESD 1.1 %, 95 % CI 0.3 - 2.5 %), with most amenable to successful endoscopic treatment (87.7 %, 95 % CI 81.1 - 93.1 %). Surgery was limited to 2.7 % of the lesions, 0.5 % due to AEs. No data of TEMS were available for LST. Conclusions  EMR and ESD are both effective and safe and are associated with a very low risk of procedure related mortality.

Clinical outcomes of endoscopic submucosal dissection for laterally spreading tumors involving the dentate line

OBJECTIVE

Endoscopic submucosal dissection (ESD) for laterally spreading tumors (LST) involving the dentate line (LST-DL) is challenging because of the specific anatomical features of the anorectum. This study aimed to evaluate the efficacy and safety of ESD for LST-DL.

METHODS

Consecutive patients with LST-DL who had undergone ESD at our hospital between January 2010 and December 2015 were retrospectively enrolled in this study. Rates of en bloc resection, R0 resection, and complications, pathological characteristics, and tumor recurrence were analyzed and compared with those of LST in the rectum not involving the dentate line (LST-NDL).

RESULTS

Altogether 49 patients with LST-DL (median age 63 years; 39 women; median lesion size 57 mm; median follow-up period of 24 months) and 96 patients with LST-NDL (median age 67 years; 31 women; median lesion size 47 mm; median follow-up period of 31 months) were enrolled. En bloc resection (93.9% [46/49] vs 94.8% [91/96]) and en bloc R0 resection rates (83.7% [41/49] vs 88.5% [85/96]), respectively, for LST-DL and LST-NDL, with no significant differences. However, ESD for LST-DL had a longer procedure time (77 min vs 54 min, P = 0.02), a greater postprocedural perianal pain rate (28.6% vs 0%, P < 0.001), and more anal strictures (4.1% vs 0%, P = 0.04). The complication rates of perforation, bleeding and fever, recurrence rate, and pathological characteristics did not differ between the two groups.

CONCLUSIONS

ESD is a safe and effective therapeutic modality for LST-DL. However, this procedure should be performed by experienced endoscopists and the difficulty needs to be fully considered.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Safety of simultaneous endoscopic submucosal dissection for two large colorectal neoplasias in the same patient

BACKGROUND/AIMS

Multiple large colorectal lesions requiring endoscopic submucosal dissection (ESD) are sometimes diagnosed during colonoscopy. We evaluated the feasibility and safety of ESD of two colorectal lesions in one session.

MATERIALS AND METHODS

The lesions of 16 patients who underwent two ESD procedures in a single session (double ESD group) from November 2009 to July 2014 were matched with those of 64 patients who underwent a single ESD procedure (single ESD group) based on the size and location of the lesion and presence of submucosal fibrosis.

RESULTS

The net ESD time per patient was longer in double ESD group than in single ESD group (104.0±36.2 vs. 59.1±39.2 min, p<0.001). The net ESD time per lesion tended to be shorter in double ESD group than in single ESD group (49.6±30.0 vs. 59.1±39.2 min, p=0.077). The en bloc resection and curative resection rates did not differ between double ESD and single ESD groups (93.8 % vs. 98.4%, p=0.262; 90.6 % vs. 84.4 %, p=0.534, respectively). The intra- and postprocedural bleeding rates were 12.5% and 0% in double ESD group and 15.6% and 3.1% in single ESD group, respectively. Perforation occurred in two (6.3%) in double ESD group and in six (9.4%) in single ESD group (p=0.715).

CONCLUSION

Compared with the single ESD, two simultaneous colorectal ESD procedures in a patient did not increase complications; the en bloc and curative resection rates were similar when performed a single ESD procedure and two simultaneous ESD procedures.

Clinicopathological feature and treatment outcome of patients with colorectal laterally spreading tumors treated by endoscopic submucosal dissection

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) is an advanced technique that can be used to treat precancerous and early colorectal neoplasms by facilitating en bloc resection regardless of tumor size. In our study, we investigated the clinicopathological feature and the treatment outcome of patients with colorectal laterally spreading tumors (LSTs) that were treated by ESD.

METHODS

The study enrolled all of 210 patients with colorectal LSTs who underwent ESD. Clinical outcomes were analyzed by retrospectively reviewing medical records.

RESULTS

A cancerous pit pattern (Vi/Vn) was more common in pseudo-depressed (PD) subtype than in flat elevated (FE) subtype. The incidence of adenocarcinoma in the PD subtype and nodular mixed (NM) subtypes was significantly higher than in the homogenous (HG) subtype and FE subtype. The en bloc and R0 resection rates were 89.0% and 85.7%, respectively. The bleeding and perforation rates were 5.2% and 1.9%, respectively. The mean procedure time was much longer in the PD subtype than in the FE subtype. The en bloc resection rate was significantly higher in the NM subtype than in the HG subtype. However, there were no statistically significant differences in mean procedure time, en bloc resection rate, R0 resection rate, bleeding rate, or perforation rate between LST-granular and LST-nongranular types.

CONCLUSIONS

These results indicate that ESD is acceptable for treating colorectal LSTs concerning en bloc resection, curative resection, and risk of complications. Careful consideration is required for complete resection of the PD subtype and NM subtype because of their higher malignant potential.

Risk factors for procedure-related complications after endoscopic resection of colorectal laterally spreading tumors

Colorectal laterally spreading tumors (LSTs) are large and flat elevated neoplasms with diameters of at least 10 mm. Endoscopic resection of LSTs, with their large size and broad base, is difficult and dangerous compared with the resection of polypoid neoplasms. This study aimed to determine the risk factors for procedure-related complications including bleeding and perforation after endoscopic resection of LSTs.Patients with colorectal LST undergoing endoscopic resection at 5 university hospitals in Honam Province of South Korea were enrolled, and their records about patients, lesions, and procedure parameters associated with the occurrence of complications were reviewed retrospectively. Logistic regression analysis was performed to identify risk factors for complications.The frequency of comorbidities in bleeding group was significantly higher than in the no bleeding group. The frequency of bleeding was significantly higher in lesions with adenocarcinoma than in lesions with low or high-grade dysplasia. The frequency of bleeding was significantly higher in piecemeal resection than in en bloc resection. The frequency of perforation was significantly higher in endoscopic mucosal resection-precutting (EMR-P) than in endoscopic mucosal resection (EMR) or endoscopic submucosal dissection. The mean procedure duration was significantly longer in the perforation group than in the no perforation group. On multivariate analysis, patient comorbidity and histologic grade of the lesion were significant independent risk factors for bleeding, whereas EMR-P was a significant independent risk factor for perforation after endoscopic resection.This study demonstrated that patient comorbidity and histologic grade of lesion were significant independent risk factors for bleeding, and EMR-P was a significant independent risk factor for perforation after endoscopic resection of colorectal LSTs.

Recurrence rate of lateral margin-positive cases after en bloc endoscopic submucosal dissection of colorectal neoplasia

PURPOSE

We aimed to evaluate the recurrence rate of colorectal neoplasia showing histologic lateral margin involvement after en bloc endoscopic submucosal dissection (ESD).

METHODS

We reviewed 527 colorectal lesions that were removed by en bloc ESD from 2005 to 2013 and followed by endoscopy. Based on the postprocedural pathologic reports, the lesions were categorized as follows: lesions with clear deep and positive lateral margins (n = 63) and lesions with R0 resection (n = 299).

RESULTS

The tumor size was 45.7 ± 21.1 mm in the lateral margin-positive group and 30.6 ± 15.1 in the R0 group (P < 0.001). Procedure time was longer in the lateral margin-positive group than in the R0 group (94.3 ± 75.1 vs. 54.1 ± 48.9 min; P < 0.001). Lateral margin positivity was associated with ESD time ≥ 120 min in the multivariate analysis. Compared with 0-I morphology, LST-G was significantly associated with the lateral margin positivity. The volume of ESD experience in endoscopists may also be associated with the lateral margin positivity. Histologic reassessment of the specimen suggested that 32.2% of lateral margin-positive cases based on the initial pathology report were false-positive lateral margin involvement. The 5-year cumulative recurrence rate was 0.6% in the R0 group and 5% in the margin-positive group (P = 0.198).

CONCLUSIONS

The local recurrence rate was not higher in lateral margin-positive cases than in R0 resection cases if the colorectal epithelial neoplasia was removed in an en bloc manner using ESD. Meticulous pathologic interpretation may reduce unnecessarily frequent surveillance after en bloc ESD.

Single-center implementation of endoscopic submucosal dissection (ESD) in the colorectum: Low recurrence rate after intention-to-treat ESD

BACKGROUND AND AIM

Colorectal endoscopic submucosal dissection (ESD) shows higher R0 resection and lower local recurrence rates than endoscopic mucosal resection (EMR) in Japan. In Europe, independent learning of ESD in the colorectum is feasible, but yet to be analyzed for curative resection and recurrence rates.

METHODS

After experimental training under supervision by Japanese experts (T.O., N.Y.), three endoscopists independently carried out 83 ESD procedures intention-to-treat for lesions in the entire colorectum of 67 patients in a prospective registry (November 2009 to June 2016).

RESULTS

ESD was feasible in 80 (96%) colorectal neoplasias (mean diameter 33.6 [± 1.8] mm), and three more required conversion to piecemeal EMR. The lesions were adenomas in 66% with low-grade intraepithelial neoplasia (LGIN), 29% with high-grade intraepithelial neoplasia, and 5% with carcinomas (G2, pT1). ESD had to be facilitated by the final use of snaring (hybrid-ESD, n = 45), especially in the initial learning period. En-bloc resection rate was 85%. Complications were microperforations (7%, conducive to one hemicolectomy), and delayed bleeding (1%) without mortality or long-term morbidity. Residual adenomas with LGIN (5%) after hybrid-ESD did not recur after endoscopic ablation. All malignant neoplasias (34%) were curatively resected without recurrence after a mean follow up of 19.5 (± 3.2) months.

CONCLUSIONS

During independent ESD learning in the colorectum, ESD intention-to-treat showed a low recurrence rate after appropriate training, and hybrid-ESD showed acceptable complication and recurrence rates, justifying hybrid-ESD as a strategy for self-completion and rescue.

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

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinicopathological features of laterally spreading colorectal tumors and their association with advanced histology and invasiveness: An experience from Honam province of South Korea: A Honam Association for the Study of Intestinal Diseases (HASID)

Background and aims

Laterally spreading colorectal tumors (LSTs) are divided into four subtypes, including homogenous (HG), nodular mixed (NM), flat elevated (FE), and pseudo-depressed (PD), based on their different endoscopic morphologies. The aim of this study was to investigate the clinicopathological significance of LST subtypes and their association with advanced histology.

Methods

We investigated the medical records of consecutive patients with LST who initially underwent endoscopic resection at five university hospitals in Honam province of South Korea between January 2012 and December 2013. A total of 566LST lesions removed via endoscopic procedures were collected retrospectively for data analysis.

Results

The PD, FE, and NM subtypes were more common in the distal colon and the HG subtype in the proximal colon. The PD subtype had the biggest tumor size, followed by the NM subtype. The frequency of adenomatous pit pattern was significantly higher in the HG, NM, and FE subtypes than in the PD subtype. In contrast, the frequency of cancerous pit pattern was significantly higher in the PD subtype than in the other three subtypes. The rate of advanced histology (high-grade dysplasia or carcinoma) among the LSTs was 36.0%. The risk of advanced histology increased in the distal colon compared with the proximal colon. The PD subtype had the highest incidence of villous component, advanced histology,submucosal invasion, and postprocedure perforation among the four subtypes. The distal colon as tumor site, larger tumor size, PD subtype, and villous component were associated with a statistically significant increased risk of advanced histology.

Conclusion

Our results indicate that the location, size, endoscopic subtype, and histologic component of the LSTs are associated with an increased risk of advanced histology. Therefore, these clinicopathological parameters may be useful in selecting therapeutic strategies in the clinical setting.

Colorectal endoscopic submucosal dissection: predictors and neoplasm-related gradients of difficulty

BACKGROUND AND STUDY AIM

 The role of colorectal endoscopic submucosal dissection (ESD) is standardized in Japan and East Asia, but technical difficulties hinder its diffusion. The aim was to identify predictors of difficulty for each neoplasm type.

METHODS

 A competent operator performed all procedures. ESD difficulty was defined as: en bloc with a slow speed (< 0.07 cm ² /min; 30 × 30 mm neoplasm in > 90 min), conversion to endoscopic mucosal resection, or resection abandonment. Pre- and intraoperative difficulty variables were defined according to standard criteria, and evaluated separately for the rectum and colon. Difficulty predictors and gradients were evaluated by the multivariate logistic regression model.

RESULTS

 A total of 140 ESDs were included: 110 in the colon and 30 in the rectum. Neoplasms were laterally spreading tumors - granular type (LST-G) in 85 cases (61 %); the median longer axis was 30 mm (range 15 - 180 mm); a scar was present in 15 cases (11 %). ESD en bloc resection and difficulty rates were 85 % (n = 94) and 35 % (n = 39) in the colon, and 73 % (n = 22) and 50 % (n = 15) in the rectum ( P  = 0.17 and 0.28, respectively). The scar was the only preoperative predictor of difficulty in the rectum (odds ratio [OR] 12.3, 95 % confidence interval [CI] 1.27 - 118.36), whereas predictors in the colon were: scar (OR 12.7, 95 %CI 1.15 - 139.24), LST - nongranular type (NG) (OR 10.5, 95 %CI 1.20 - 55.14), and sessile polyp morphology (OR 3.1, 95 %CI 1.18 - 10.39). Size > 7 - ≤ 12 cm ² (OR 0.20, 95 %CI 0.06 - 0.74) and operator experience > 120 procedures (OR 0.19, 95 %CI 0.04 - 0.81) were predictors for a easy procedure. No intraoperative predictors of difficulty were identified in the rectum, whereas predictors in the colon were: severe submucosal fibrosis (OR 21.9, 95 %CI 2.11 - 225.64), ineffective submucosal exposure by gravity countertraction (OR 12.3, 95 %CI 2.43 - 62.08), and perpendicular submucosal dissection approach (OR 5.2, 95 %CI 1.07 - 25.03). When experience was /= 90, preoperative gradient of colonic ESD difficulty was the highest for LST-NGs (scar positive and negative up to 47 % and 20 %, respectively), intermediate for sessile polyps with scar (up to 23 %), and the lowest for LST-Gs (< 8 %). Different difficulty gradients between neoplasm types persisted with increasing experience: LST-NG rate up to 14 % after 120 procedures.

CONCLUSIONS

 Colonic and rectal ESD difficulty has qualitative differences. Preoperative predictors should be considered to identify the difficulty gradient of each neoplasm type and the appropriate setting for ESD.

A randomized controlled trial of prophylactic antibiotics in the prevention of electrocoagulation syndrome after colorectal endoscopic submucosal dissection

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is currently commonly performed, but colorectal ESD has a substantial risk of adverse events, including post-ESD electrocoagulation syndrome (PEECS). We investigated whether the use of prophylactic antibiotics can reduce the occurrence of PEECS.

METHODS

Patients who underwent colorectal ESD were randomly assigned to 1 of 2 treatment regimens. Ampicillin and/or sulbactam mixed with normal saline solution was administered 1 hour before ESD in group 1 then additionally injected every 8 hours twice more. In group 2, normal saline solution without antibiotics was administered following the same schedule. We investigated the characteristics of the patients and tumors, the incidence of PEECS, laboratory findings, and the visual analog scale (VAS) score for abdominal pain measured on the morning after ESD.

RESULTS

A total of 100 cases (50 per group) were finally analyzed, and 97 tumors were successfully resected en bloc. The number of patients having C-reactive protein (CRP) levels ≥1 mg/dL and the number of patients having VAS scores for abdominal pain ≥1 were greater in group 2 than in group 1 (P = .008 and .023, respectively). The incidence of PEECS in group 2 also was higher than that in group 1 (1 and 8 in groups 1 and 2, respectively; P = .031).

CONCLUSIONS

The prophylactic use of ampicillin and/or sulbactam in colorectal ESD is associated with reduced risk of PEECS, decreased CRP levels, and decreased abdominal pain. The use of prophylactic antibiotics in colorectal ESD may be an effective tool for reducing the risk of PEECS. (Clinical trial registration number: KCT0001102.).