JGES guidelines for colorectal endoscopic submucosal dissection/endoscopic mucosal resection

Multidisciplinary Treatment Strategy for Early Colon Cancer: A Review-An English Version

Treatment for early colon cancer has progressed rapidly, with endoscopic resection and minimally invasive surgery. It is important to select patients without risk of lymph node metastasis before deciding on endoscopic resection for early colon cancer treatment. Pathological risk factors include histologic grade of cancer cell differentiation, lymphovascular invasion, perineural invasion, tumor budding, and deep submucosal invasion. These risk factors for predicting lymph node metastasis are crucial for determining the treatment strategy of endoscopic excision and radical resection for early colon cancer. A multidisciplinary approach is emphasized to establish a treatment strategy for early colon cancer to minimize the risk of complications and obtain excellent oncologic outcomes by selecting an appropriate treatment optimized for the patient's stage and condition. Therefore, we aimed to review the optimal multidisciplinary treatment strategies, including endoscopy and surgery, for early colon cancer.

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

Background and aims

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

Methods

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

Results

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

Conclusions

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

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

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

Endoscopic methods for the detection and treatment of gastric cancer

PURPOSE OF REVIEW

The intent of this review is to describe new advances in endoscopic approaches to surveillance and management of gastric cancer.

RECENT FINDINGS

There are new endoscopic techniques and approaches that have improved the detection of gastric cancer, including narrow band imaging, confocal laser endocytomicroscopy and magnetically controlled capsule endoscopy. This article highlights the role of endoscopic submucosal dissection in the treatment of focal and diffuse gastric dysplasia and early gastric cancer with a discussion of indications, complications and outcomes. We review several recent guidelines addressing the surveillance strategies for individuals at high-risk for developing gastric cancer, such as those with atrophic gastritis and intestinal metaplasia, how gastric dysplasia and early gastric cancer can be endoscopically managed, and recommended surveillance after endoscopic intervention.

SUMMARY

Endoscopic approaches are evolving rapidly that will improve detection of dysplasia and early gastric cancer in high-risk individuals. Surveillance guidelines from various international societies reflect differences in local experience and prevalence of gastric cancer. Endoscopic submucosal dissection is now widely accepted as a first-line approach to early gastric cancers that can be resected en-bloc .

Effect of hypoalbuminemia on short-term outcomes after colorectal cancer surgery: A propensity score matching analysis

Purpose

The purpose of our study was to investigate the effect of pre-operative hypoalbuminemia on the short-term outcomes after primary colorectal cancer (CRC) surgery.

Materials and methods

The retrospective study enrolled CRC patients who underwent primary surgery from January 2011 to December 2021 in a single teaching hospital. The short-term outcomes were compared between the hypoalbuminemia group and the normal group using propensity score matching (PSM). Univariate and multivariate logistic regression analyses were used for analyzing independent predictors of overall complications and major complications.

Results

A total of 7,072 patients from a single center were enrolled in this study. There were 1,078 (15.2%) patients in the pre-operative hypoalbuminemia group and 5,994 (84.8%) patients in the normal pre-operative albumin group. After 1:1 PSM, there were 1,028 patients in the hypoalbuminemia group and 1,028 patients in the normal group. No significant differences were found in baseline information between the two groups after PSM. In terms of short-term outcomes, the hypoalbuminemia group had a longer operation time (p = 0.003), greater volume of blood loss (p = 0.036), longer hospital stays (p < 0.01), higher proportion of overall complications (p = 0.003), major complications (p = 0.016), higher incidence of pneumonia and abdominal infection (p = 0.001) than the normal group after PSM. Furthermore, hypoalbuminemia was an independent predictor for overall complications (p = 0.008) and major complications (p = 0.016).

Conclusion

Pre-operative hypoalbuminemia increased overall complications and major complications after primary CRC surgery. Furthermore, hypoalbuminemia was an independent predictor for overall complications and major complications.

From advanced diagnosis to advanced resection in early neoplastic colorectal lesions: Never-ending and trending topics in the 2020s

Colonoscopy represents the most widespread and effective tool for the prevention and treatment of early stage preneoplastic and neoplastic lesions in the panorama of cancer screening. In the world there are different approaches to the topic of colorectal cancer prevention and screening: different starting ages (45-50 years); different initial screening tools such as fecal occult blood with immunohistochemical or immune-enzymatic tests; recto-sigmoidoscopy; and colonoscopy. The key aspects of this scenario are composed of a proper bowel preparation that ensures a valid diagnostic examination, experienced endoscopist in detection of preneoplastic and early neoplastic lesions and open-minded to upcoming artificial intelligence-aided examination, knowledge in the field of resection of these lesions (from cold-snaring, through endoscopic mucosal resection and endoscopic submucosal dissection, up to advanced tools), and management of complications.

Endoscopic submucosal dissection for removal of large colorectal neoplasias in an outpatient setting: a single-center series of 660 procedures in Sweden

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is a technique developed in Japan for the removal of large lesions in the GI tract. Because of the complexity of the technique, implementation in Western health care has been slow. An ESD procedure is usually followed by hospital admission. Our aim was to investigate if ESD of colorectal lesions can be performed in an outpatient setting.

METHODS

Six hundred sixty colorectal ESD procedures between 2014 and 2020 were evaluated retrospectively. All patients referred to the unit with an early colorectal neoplasm >20 mm without signs of deep invasion were considered eligible for an ESD procedure.

RESULTS

Of 660 lesions, 323 (48.9%) were localized in the proximal colon, 102 (15.5%) in the distal colon, and 235 (35.6%) in the rectum. Median lesion size was 38 mm (interquartile range, 30-50) and median procedure duration 70 minutes (interquartile range, 45-115). En-bloc resection was achieved in 620 cases (93.9%). R0 resection was achieved in 492 en-bloc resections (79.4%), whereas the number of Rx and R1 resections was 124 (20.0%) and 4 (.6%), respectively. Low-grade dysplasia was found in 473 cases (71.7%), high-grade dysplasia in 144 (21.8%), and adenocarcinoma in 34 (5.1%). Six hundred twelve procedures (92.7%) were scheduled as outpatient, and 33 of these underwent unplanned admission. Forty-eight cases (7.3%) were planned as inpatient procedures. The rate of full wall perforation was 38 (5.8%), in which 35 (92.1%) were managed endoscopically and 3 patients (7.9%) required emergency surgery. Forty-six patients (7.0%) sought medical attention within 30 days because of bleeding (21 [3.2%]), abdominal tenderness (16 [2.4%]), and other reasons (9 [1.4%]). Twenty-four of these patients were admitted for observation for a median of 2 days (range, 1-7). Ten of these patients were treated with antibiotics, and 6 patients required blood transfusion. None required additional surgery.

CONCLUSIONS

ESD of colorectal lesions can be safely performed in an outpatient setting in a well-selected patient.

Kolorektal lateral yayılımlı tümörlerde başarısız endoskopik mukozal rezeksiyon sonrası endoskopik submukozal diseksiyonun uygulanabilirliği: tek merkez deneyimi

Aim: Endoscopic mucosal resection might technically be unsuccessful (interrupted endoscopic mucosal resection) in some cases when treating large colorectal laterally spreading tumors. In the literature, data on the outcomes of the endoscopic submucosal dissection method in endoscopic mucosal resection interrupted tumors are lacking. In this study, we evaluated the results of patients who underwent endoscopic submucosal dissection for endoscopic mucosal resection interrupted laterally spreading tumors. Materials and Methods: Between February 2019 and April 2021, 8 patients with endoscopic mucosal resection interrupted colorectal laterally spreading tumors underwent endoscopic submucosal dissection. The primary endpoint was en bloc, R0, and curative resection rates of endoscopic submucosal dissection. Results: In all cases, endoscopic submucosal dissection was successfully completed. The mean tumor size was 61.5 mm (35–100 mm). The rate of en bloc resection, R0 resection and curative resection was 100%, 87.5% and 87.5% respectively. Intra-procedural perforation occurred in 1 patient (12.5%) and was successfully treated with clip application. Delayed bleeding occurred in 1 patient (12.5%), and was successfully treated with endoluminal hemostasis. Furthermore, histopathological examination revealed that laterally spreading tumors in 4 patients (50.0%) had submucosal invasion. Surgical resection was performed after endoscopic submucosal dissection in 1 patient owing to the presence of deep submucosal invasion. Conclusion: Endoscopic submucosal dissection is an effective and relatively safe method in endoscopic mucosal resection interrupted colorectal laterally spreading tumors.

Colon cancer microsatellite instability influences computed tomography assessment of regional lymph node morphology and diagnostic performance

PURPOSE

To elucidate whether a high level of microsatellite instability (MSI-high) in colon cancer influences the CT assessment of regional lymph node (rLN) morphology and diagnostic performance on predicting pathological node-negative (pN0) patients.

METHOD

We retrospectively reviewed 507 patients with cecal/proximal ascending colon cancer (age, 63.0 ± 11.6 years; MSI-stable, n = 398; MSI-high, n = 109) who underwent right hemicolectomy between July 1, 2009, and December 31, 2018. Preoperative CT images were assessed for number of rLNs, long/short diameter of the largest rLN, and CT LN grade (CTN0, low probability of metastasis; CTN1, borderline; CTN2, high probability). Sensitivity, specificity, positive predictive value and negative predictive value for predicting pN0 was calculated. Multivariable logistic regression analysis was performed. Statistical significance was defined as P < 0.05.

RESULTS

A study population of 507 patients (mean age ± standard deviation, 63.0 ± 11.6; 264 women) were evaluated. In patients with rLN metastasis, the rLN long axis (pN1: P = 0.013, pN2: P = 0.039) and short axis (pN1: P = 0.001, pN2: P = 0.009) were both longer in MSI-high tumors compared with MSI-stable tumors. High specificity for predicting pN0 was only achieved in MSI-high tumors [sensitivity_MSI-stable = 58.3% (n = 137/235), specificity_MSI-stable = 71.2% (n = 116/163); sensitivity_MSI-high = 38.4% (n = 33/86), specificity_MSI-high = 91.3% (n = 21/23)]. Multivariable logistic regression indicated MSI-high (P < 0.001, odds ratio = 3.701), smaller LN long axis (P = 0.023, odds ratio = 0.905), and lower CT LN grade (CTN0: P = 0.009, odds ratio = 2.987; CTN1: P = 0.014, odds ratio = 2.195) as significant parameters in predicting pN0.

CONCLUSION

MSI-high colon cancer is associated with larger rLNs and high specificity for predicting pN0 on CT assessment.

Real-time automated diagnosis of colorectal cancer invasion depth using a deep learning model with multimodal data (with video)

BACKGROUND AND AIMS

The optical diagnosis of colorectal cancer (CRC) invasion depth with white light (WL) and image-enhanced endoscopy (IEE) remains challenging. We aimed to construct and validate a 2-modal deep learning-based system, incorporated with both WL and IEE images (named Endo-CRC) in estimating the invasion depth of CRC.

METHODS

Samples were retrospectively obtained from 3 hospitals in China. We combined WL and IEE images into image pairs. Altogether, 337,278 image pairs from 268 noninvasive and superficial CRC and 181,934 image pairs from 82 deep CRC were used for training. A total of 296,644 and 4528 image pairs were used for internal and external tests and for comparison with endoscopists. Thirty-five videos were used for evaluating the real-time performance of the Endo-CRC system. Two deep learning models, solely using either WL (model W) or IEE images (model I), were constructed to compare with Endo-CRC.

RESULTS

The accuracies of Endo-CRC in internal image tests with and without advanced CRC were 91.61% and 93.78%, respectively, and 88.65% in the external test, which did not include advanced CRC. In an endoscopist-machine competition, Endo-CRC achieved an expert comparable accuracy of 88.11% and the highest sensitivity compared with all endoscopists. In a video test, Endo-CRC achieved an accuracy of 100.00%. Compared with model W and model I, Endo-CRC had a higher accuracy (per image pair: 91.61% vs 88.27% compared with model I and 91.61% vs 81.32% compared with model W).

CONCLUSIONS

The Endo-CRC system has great potential for assisting in CRC invasion depth diagnosis and may be well applied in clinical practice.

Endoscopic transcecal appendectomy: a new endotherapy for appendiceal orifice lesions

BACKGROUND

Endoscopic transcecal appendectomy (ETA) has been reported as a minimally invasive alternative procedure for lesions involving the appendiceal orifice. The aim of this case series study was to evaluate the feasibility, safety, and effectiveness of ETA for lesions at the appendiceal orifice.

METHODS

This retrospective study included consecutive patients with appendiceal orifice lesions who underwent ETA between December 2018 and March 2021. The primary outcome was technical success. The secondary outcomes included postoperative adverse events, postoperative hospital stay, and recurrence.

RESULTS

13 patients with appendiceal orifice lesions underwent ETA during the study period. The median lesion size was 20 mm (range 8-50). Lesions morphologies were polypoid lesions (n = 5), laterally spreading tumors (n = 4), and submucosal lesions (n = 4). Technical success with complete resection was achieved in all 13 cases. There were no postoperative bleeding, perforation, or intra-abdominal abscess. The median length of hospital stay after ETA was 8 days (range 6-18). There was no tumor recurrence during a median follow-up of 17 months (range 1-28).

CONCLUSIONS

ETA is feasible, safe, and effective for complete resection of appendiceal orifice lesions. Larger, multicenter, prospective studies are needed to further assess this technique.

Minimally invasive treatments for early colorectal cancer: comparison of endoscopic resection and laparoscopic surgery

PURPOSE

Endoscopic treatment and laparoscopic surgery are minimally invasive options for early treatment of colorectal cancer, however, more evidence of the long-term outcomes between the two procedures is needed to guide clinical decisions. Therefore, this study aimed to compare the oncologic outcomes between endoscopic and laparoscopic treatment for early colorectal cancer.

METHODS

The study group included 60 patients who underwent endoscopic treatment and 38 patients who underwent laparoscopic surgery for early colorectal adenocarcinoma between January 2010 and December 2013 at a single study site.

RESULTS

Histopathological diagnoses showed that 43 (78.3%) carcinomas in the endoscopic submucosal dissection group were mucosal to sm1, 13 (21.7%) were sm2 or deeper, and 17 high-risk cases (28.3%) in the endoscopic group underwent additional surgery. The median operation time, time to sips of water, and length of hospital stay were significantly shorter in the endoscopic group than in the laparoscopic group. The overall survival rates of patients in the endoscopic group and laparoscopic groups were 91.5% and 87.4%, respectively (P=0.391), and the disease-free survival rates were 90.4% and 87.4% (P=0.614), respectively. Systemic recurrences occurred in two patients (1.6%) in the endoscopic group and one patient (2.0%) in the laparoscopic group. Local recurrence combined with systemic recurrence in one patient (0.8%) in the endoscopic group.

CONCLUSION

Endoscopic resection for early colorectal cancer can be performed safely with better short-term outcomes and comparable long-term oncological outcomes compared to laparoscopic surgery.

Training program using a traction device improves trainees' learning curve of colorectal endoscopic submucosal dissection

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) requires advanced endoscopic skill. For safer and more reliable ESD implementation, various traction devices have been developed in recent years. The purpose of this research was to evaluate whether an ESD training program using a traction device (TD) would contribute to the improvement of trainees' skill acquisition.

METHODS

The differences in treatment outcomes and learning curves by the training program were compared before and after the introduction of TD (control group: January 2014 to March 2016; TD group: April 2016 to June 2018).

RESULTS

A total of 316 patients were included in the analysis (TD group: 202 cases; control group: 114 cases). The number of cases required to achieve proficiency in ESD techniques was 10 in the TD group and 21 in the control group. Compared to the control group, the TD group had a significant advantage in ESD self-completion rate (73.8% vs. 58.8%), dissection speed (19.5 mm²/min vs. 15.9 mm²/min), en bloc resection rate (100% vs. 90%), and R0 resection rate (96% vs. 83%).

CONCLUSIONS

The rate of colorectal ESD self-completion by trainees improved immediately after the start of the training program using a traction device compared to the conventional method, and the dissection speed tended to increase linearly with ESD experience. We believe that ESD training using a traction device will help ESD techniques to be performed safely and reliably among trainees.

Feasibility and safety of endoscopic submucosal dissection for lesions in proximity to a colonic diverticulum

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) for diverticulum-associated colorectal lesions is generally contraindicated because of the high risk of perforation. Several studies on patients with such lesions treated with ESD have been reported recently. However, the feasibility and safety of ESD for lesions in proximity to a colonic diverticulum (D-ESD) have not been fully clarified. The aim of this study was to evaluate the feasibility and safety of D-ESD.

METHODS

D-ESD was defined as ESD for lesions within approximately 3 mm of a diverticulum. Twenty-six consecutive patients who underwent D-ESD were included. Two strategic approaches were used depending on whether submucosal dissection of the diverticulum-related part was required (strategy B) or not (strategy A). Treatment outcomes and adverse events associated with each strategy were analyzed.

RESULTS

The en bloc resection rate was 96.2%. The rates of R0 and curative resection in strategies A and B were 80.8%, 73.1%, 84.6%, and 70.6%, respectively. Two cases of intraoperative perforation and one case of delayed perforation occurred. The delayed perforation case required emergency surgery, but the other cases were managed conservatively.

CONCLUSION

D-ESD may be a feasible treatment option. However, it should be performed in a high-volume center by expert hands because it requires highly skilled endoscopic techniques.

New traction method (traction ring) for colorectal endoscopic submucosal dissection

OBJECTIVES

Colorectal endoscopic submucosal dissection (ESD) is challenging because of the difficulty in adequately visualizing the submucosal layer. Many traction methods have been developed to facilitate submucosal dissection; however, they are not widely applied. Therefore, we designed a new traction device, a traction ring, and conducted this pilot study to evaluate its feasibility and safety for colorectal ESD.

METHODS

Twenty patients with colorectal lesions who underwent traction ring-assisted ESD were retrospectively included. The main outcomes included en bloc resection rate, R0 resection rate, procedure time, resection time, and intraoperative and postoperative complications.

RESULTS

The median procedure time was 74.5 min (range 35-269 min). The median resection time was 55 min (range 25-209 min). Application of the traction system accounted for only 2.7% of the entire procedure time. The en bloc resection rate was 95.0% (19/20), whereas the R0 resection rate was 90.0% (18/20). All traction rings were successfully set and retrieved. Significant intraoperative bleeding was not observed. One patient experienced perforation after treatment, but no further intervention was required. No delayed complications were observed within 1 month post-ESD.

CONCLUSION

Traction ring is an effective and safe method for colorectal ESD and can be used at any location in the colorectum.

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

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

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Colon Polypectomy with Endoscopic Submucosal Dissection and Endoscopic Full-Thickness Resection

Endoscopic resection has become the gold standard for the management of most of the large colorectal polyps. Various endoscopic resection techniques include endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and endoscopic full-thickness resection (EFTR). ESD is a minimally invasive method for the resection of advanced lesions in the gastrointestinal (GI) tract to achieve en-bloc resection. While, EFTR is more commonly used in lesions with suspected deeper submucosal invasion, lesions originating from muscularis propria, or those with advanced fibrosis. This article reviews the indications, technique, and adverse events for use of ESD and EFTR in the colon.

Patient Selection, Risks, and Long-Term Outcomes Associated with Colorectal Polyp Resection

The 2 most significant complications of colonoscopy with polypectomy are bleeding and perforation. Although the incidence rates are generally low (<1%), these can be avoided by recognizing pertinent risk factors, which can be patient, polyp, and technique/device related. Endoscopists should be equipped to manage bleeding and perforation. Currently available devices and techniques to achieve hemostasis and manage colon perforations are reviewed.

Effect of endoscopic submucosal dissection on histologic diagnosis in Barrett's esophagus visible neoplasia

BACKGROUND AND AIMS

Data are limited on the role of endoscopic submucosal dissection (ESD) as a potential diagnostic and staging tool in Barrett's esophagus (BE) neoplasia. We aimed to evaluate the frequency and factors associated with change of histologic diagnosis by ESD compared with pre-ESD histology.

METHODS

This was a multicenter, prospective cohort study of patients who underwent ESD for BE visible neoplasia. A change in histologic diagnosis was defined as "upstaged" or "downstaged" if the ESD specimen had a higher or lower degree, respectively, of dysplasia or neoplasia when compared with pre-ESD specimens.

RESULTS

Two hundred five patients (median age, 69 years; 81% men) with BE visible neoplasia underwent ESD from 2016 to 2021. Baseline histology was obtained using forceps (n = 182) or EMR (n = 23). ESD changed the histologic diagnosis in 55.1% of cases (113/205), of which 68.1% were upstaged and 31.9% downstaged. The frequency of change in diagnosis after ESD was similar whether baseline histology was obtained using forceps (55.5%) or EMR (52.2%) (P = .83). In aggregate, 23.9% of cases (49/205) were upstaged to invasive cancer on ESD histopathology. On multivariate analysis, lesions in the distal esophagus and gastroesophageal junction (odds ratio, 2.1; 95 confidence interval, 1.1-3.9; P = .02) and prior radiofrequency ablation (odds ratio, 2.5; 95% confidence interval, 1.2-5.5; P = .02) were predictors of change in histologic diagnosis.

CONCLUSIONS

ESD led to a change of diagnosis in more than half of patients with BE visible neoplasia. Selective ESD can serve as a potential diagnostic and staging tool, particularly in those with suspected invasive disease. (Clinical trial registration number: NCT02989818.).

The usefulness of combining the pocket-creation method with a traction device using a scissor-type knife for colorectal endoscopic submucosal dissection

INTRODUCTION

Technical issues and long procedure time still remain a concern in colorectal endoscopic submucosal dissection (ESD). We examined the usefulness of combining the pocket-creation method (PCM) with a traction device (S-O clip; SO) using a scissor-type knife (Clutch Cutter 3.5 mm; CC) for decreasing ESD procedure time.

METHODS

We retrospectively analyzed 95 ESD cases of PCM + SO + CC managed from August 2017 to April 2020 and 103 cases of PCM + CC treated from July 2016 to July 2017. We compared these two groups through propensity score matching. The main outcome was the analysis of the ESD procedure times under various conditions in each group.

RESULTS

After matching, 52 cases in the PCM + SO + CC and PCM + CC groups were analyzed. The PCM + SO + CC group showed a significantly shorter ESD procedure time than the PCM + CC group (57.8 ± 31.4 vs. 81.7 ± 33.5 min, p < 0.01). Additionally, the ESD procedure time was significantly shorter in the PCM + SO + CC group than in the PCM + CC group: tumor size (tumor size < 40 mm: 45.6 ± 15.8 vs. 72.7 ± 22.9 min, p < 0.01; tumor size ≥ 40 mm: 83.1 ± 40.1 vs. 111.8 ± 45.3 min, p = 0.04), tumor location (right side: 64.7 ± 33.3 vs. 81.0 ± 29.7 min, p = 0.03; left side: 50.5 ± 28.0 vs. 82.3 ± 36.9 min, p < 0.01), tumor morphology (polypoid: 39.2 ± 18.6 vs. 74.7 ± 28.6 min, p < 0.01; nonpolypoid: 62.3 ± 32.3 vs. 84.5 ± 35.2 min, p < 0.01), endoscopist (expert: 67.3 ± 41.2 vs. 91.9 ± 40.2 min, p = 0.02; nonexpert: 50.4 ± 18.3 vs. 73.6 ± 24.9 min, p < 0.01), and fibrosis (severe fibrosis: 82.0 ± 20.5 vs. 99.8 ± 40.4 min, p = 0.169; non-severe fibrosis: 52.1 ± 23.8 vs. 75.6 ± 29.0 min, p < 0.01).

CONCLUSIONS

The combination of the PCM and SO using CC achieved a reduction in the colorectal ESD procedure time.

Prophylactic clip closure for mucosal defects is associated with reduced adverse events after colorectal endoscopic submucosal dissection: a propensity-score matching analysis

Background

It is unclear whether prophylactic endoscopic closure after colorectal endoscopic submucosal dissection (ESD) reduces the risk of postoperative adverse events due to variability in lesion characteristics. Therefore, we conducted a retrospective study using propensity score matching to evaluate the efficacy of prophylactic clip closure in preventing postoperative adverse events after colorectal ESD.

Methods

This single-center retrospective cohort study included 219 colorectal neoplasms which were removed by ESD. The patients were allocated into the closure and non-closure groups, which were compared before and after propensity-score matching. Post-ESD adverse events including major and minor bleeding and delayed perforation were compared between the two groups.

Results

In this present study, 97 and 122 lesions were allocated to the closure and non-closure groups, respectively, and propensity score matching created 61 matched pairs. The rate of adverse events was significantly lower in the closure group than in the non-closure group (8% vs. 28%, P = 0.008). Delayed perforation occurred in two patients in the non-closure group, whereas no patient in the closure group developed delayed perforation. In contrast, there were no significant differences in other postoperative events including the rate of abdominal pain; fever, white blood cell count, and C-reactive protein; and appetite loss between the two groups.

Conclusions

Propensity score matching analysis demonstrated that prophylactic closure was associated with a significantly reduced rate of adverse events after colorectal ESD. When technically feasible, mucosal defect closure after colorectal ESD may result in a favorable postoperative course.

Geriatric nutritional risk index as a prognostic indicator in elderly patients with early colorectal cancer undergoing endoscopic submucosal dissection

OBJECTIVES

Data on the long-term outcomes of endoscopic submucosal dissection (ESD) performed in elderly patients with early colorectal cancer (CRC) are limited. We analyzed the prognosis of elderly CRC patients, not only from the viewpoint of treatment curability but also from the patients' baseline physical condition assessed by several indexes.

METHODS

A retrospective analysis of 729 patients aged ≥75 years who underwent ESD for Tis/T1 CRC in 16 institutions was conducted. The patients were classified into three groups based on curability: curative ESD (Group A, n = 582), non-curative ESD with additional surgery (Group B, n = 60), and non-curative ESD without additional surgery (Group C, n = 87). Overall survival (OS) was compared among the groups, and factors associated with reduced OS were investigated.

RESULTS

The median follow-up periods in Groups A, B, and C were 41, 49, and 46 months, respectively (P = 0.62), during which 92 patients died. Two patients (0.3%) in Group A, none (0%) in Group B, and three (3.4%) in Group C died of CRC. Three-year OS rates in Groups A, B, and C were 93.9%, 96.1%, and 90.1%, respectively, without a significant difference (P = 0.07). Multivariate analysis indicated low (<96.3) geriatric nutritional risk index (GNRI) as the sole independent predictor for reduced OS (hazard ratio 3.37; 95% confidence interval 2.18-5.22; P < 0.0001).

CONCLUSIONS

Low GNRI, but not the curability attained by ESD, was independently associated with reduced OS in patients with early CRC aged ≥75 years.

Artificial intelligence-assisted colonoscopy: a narrative review of current data and clinical applications

Colonoscopy is the reference standard procedure for the prevention and diagnosis of colorectal cancer, which is a leading cause of cancer-related deaths in Singapore. Artificial intelligence systems are automated, objective and reproducible. Artificial intelligence-assisted colonoscopy has recently been introduced into clinical practice as a clinical decision support tool. This review article provides a summary of the current published data and discusses ongoing research and current clinical applications of artificial intelligence-assisted colonoscopy.

The COlorectal NEoplasia Endoscopic Classification to Choose the Treatment classification for identification of large laterally spreading lesions lacking submucosal carcinomas: A prospective study of 663 lesions

Introduction

Optical diagnosis is necessary when selecting the resection modality for large superficial colorectal lesions. The COlorectal NEoplasia Endoscopic Classification to Choose the Treatment (CONECCT) encompasses overt (irregular pit or vascular pattern) and covert (macroscopic features) signs of carcinoma in an all‐in‐one classification using validated criteria. The CONECCT IIC subtype corresponds to adenomas with a high risk of superficial carcinoma that should be resected en bloc with free margins.

Methods

This prospective multicentre study investigated the diagnostic accuracy of the CONECCT classification for predicting submucosal invasion in colorectal lesions >20 mm. Optical diagnosis before en bloc resection by endoscopic submucosal dissection (ESD) was compared with the final histological diagnosis. Diagnostic accuracy for the CONECCT IIC subtype was compared with literature‐validated features of concern considered to be risk factors for submucosal invasion (non‐granular large spreading tumour [NG LST], macronodule >1 cm, SANO IIIA area, and Paris 0‐IIC area).

Results

Six hundred 63 lesions removed by ESD were assessed. The en bloc, R0, and curative resection rates were respectively 96%, 85%, and 81%. The CONECCT classification had a sensitivity (Se) of 100%, specificity (Sp) of 26.2%, positive predictive value of 11.6%, and negative predictive value (NPV) of 100% for predicting at least submucosal adenocarcinoma. The sensitivity of CONECCT IIC (100%) to predict submucosal cancer was superior to all other criteria evaluated. COlorectal NEoplasia Endoscopic Classification to Choose the Treatment IIC lesions constituted 11.5% of all submucosal carcinomas.

Conclusion

The CONECCT classification, which combines covert and overt signs of carcinoma, identifies with very perfect sensitivity (Se 100%, NPV 100%) the 30% of low‐risk adenomas in large laterally spreading lesions treatable by piecemeal endoscopic mucosal resection or ESD according to expertise without undertreatment. However, the low specificity of CONECCT leads to a large number of potentially not indicated ESDs for suspected high‐risk lesions.

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.

Vertical tumor margin of endoscopic resection for T1 colorectal carcinoma affects the prognosis of patients undergoing additional surgery

BACKGROUND

Vertical tumor margin-negative T1 colorectal carcinoma (CRC) is an absolute curative condition following complete endoscopic resection (ER). However, the influence on prognosis in relation to vertical tumor margin is unclear. Therefore, we evaluated the influence of the distance from vertical tumor margin to resected specimen edge (vertical margin distance) of ER for T1b (submucosal invasion depth > 1000 μm) CRC on the prognosis of patients undergoing additional surgery after ER.

METHODS

In total, 215 consecutive patients with T1b CRC who underwent additional surgery after ER at Hiroshima University Hospital between February 1992 and June 2019 were enrolled. We assessed 191 patients without lymph node metastases at the additional surgery. The specimens resected by ER were classified into three groups based on the vertical margin distance: patients with a vertical margin distance of ≥ 500 μm (Group A); patients with a vertical margin distance of < 500 μm (Group B); and patients with a positive vertical tumor margin (Group C). Subsequently, we evaluated the prognosis of the patients in relation to the clinicopathological characteristics among the three groups.

RESULTS

There were no significant differences in clinicopathological characteristics among the three groups. Group A had a significantly higher recurrence-free 5-year survival rate than Groups B and C (100%, 84.5%, and 81.8%, respectively). Similarly, Group A had a significantly higher disease-specific 5-year survival rate than Group C (100% vs. 95.5%).

CONCLUSIONS

Complete en bloc resection with sufficient submucosal layer from the invasive front (vertical margin distance > 500 μm) by ER for T1 CRC reduces the risk of metastatic recurrence after additional surgery.

Current status of diagnostic and therapeutic colonoscopy in Japan: The Japan Endoscopic Database Project

OBJECTIVES

The Japan Endoscopy Database Project was initiated to develop the world's largest endoscopy data repository. This study describes the first phase of the colonoscopy project in Japan.

METHODS

Data were aggregated offline by integrating information from the endoscopy database software from January 2015 through March 2017. The study population included all patients who underwent colonoscopy at eight centers.

RESULTS

A total of 31,395 patients who underwent 38,497 colonoscopy procedures were registered. The majority of procedures were performed for screening (n = 14,156), followed by fecal immunochemical test positivity (n = 3960), abdominal symptoms (n = 3864), post-colorectal surgery surveillance (n = 3431), post-endoscopic treatment surveillance (n = 3757), thorough pre-treatment examination (n = 2822), and therapeutic purposes (n = 6507). In the screening group, advanced cancers, early cancers, and adenomas were diagnosed endoscopically in 2.1%, 1.3%, and 28.7% of cases, respectively, while in the fecal immunochemical test-positive group, they were diagnosed in 2.5%, 1.9%, and 41.6% of cases, respectively. The incidence of complications was 0.177% and 0.152% in the screening and fecal immunochemical test-positive groups, respectively. The therapeutic procedures included 1446 cold forceps polypectomy procedures, 4770 cold snare polypectomy procedures, 368 hot biopsies, 2998 hot snare polypectomy procedures, 9775 endoscopic or piecemeal endoscopic mucosal resections, and 1660 endoscopic submucosal dissections. A total of 173 procedure-related complications (0.82%) occurred in 21,017 therapeutic procedures performed in 15,744 patients.

CONCLUSIONS

The first phase of the Japan Endoscopy Database Project established the proportions of the diagnostic and therapeutic colonoscopy procedures, and complication rates in real-world settings.

Endoscopic submucosal dissection for colorectal lesions: outcomes from a United States experience

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) is commonly used in Asia for resection of large non-pedunculated colorectal polyps (LNPCPs) and early (T1) colorectal cancers. It allows for en bloc removal and is often curative. We describe outcomes of colorectal ESD from a United States (US) academic medical center and compare this to international experiences.

METHODS

Retrospective review was performed of colonic lesions referred to the University of Chicago Medical Center for ESD from 2012 to 2020. Clinical and procedural data were collected.

RESULTS

The study included 78 lesions with mean size of 29.7 mm (range 10-100 mm). The overall en bloc resection rate was 73.1% (n = 57). Between the first and second half of the study, it improved from 61.5 to 84.6% (p = 0.02). Histology showed adenocarcinoma in fifteen lesions (19.2%). Of all neoplastic lesions (n = 68), resection with negative margins (R0) was achieved in 54 cases (79.4%). Adverse events occurred in 9 cases (11.5%), but most (n = 6, 66.7%) were successfully treated endoscopically. Follow-up endoscopy was performed in 46 patients (59.0%) at a mean interval of 6.8 months (SD ± 5.0 months) with two case of recurrent lesion (4.3%).

CONCLUSIONS

This study shows successful colorectal ESD outcomes at a US tertiary center. The en bloc resection rate was lower than other cohorts, but a learning curve was demonstrated. The R0 resection, lesion recurrence, and adverse event rates were similar to other non-Asian experiences, but not as favorable as in Asia [Fuccio et al. in Gastrointest Endosc 86:74-86.e17, 2017]. Increased ESD training in the US can help optimize utilization and outcomes.

Endoscopic submucosal dissection for colorectal neoplasia: outcomes and predictors of recurrence

Background and study aims  The role of endoscopic submucosal dissection (ESD) for colorectal lesions in Western communities is unclear and its adoption is still limited. The aim of this study is to assess the long-term outcomes of a large cohort of patients treated with colorectal ESD in a tertiary Western center. Patients and methods  A retrospective analysis was conducted on patients treated by ESD for superficial colorectal lesions between February 2011 and November 2019. The primary outcome was the recurrence rate. Secondary outcomes were en-bloc and R0 resection rates, procedural time, adverse events (AEs), and need for surgery. The curative resection rate was assessed for submucosal invasive lesions. Results  A total of 327 consecutive patients, median age 69 years (IQR 60-76); 201 men (61.5 %) were included in the analysis. Of the lesions, 90.8 % were resected in an en-bloc fashion. The rate of R0 resection was 83.1 % (217/261) and 44.0 % (29/66) for standard and hybrid ESD techniques, respectively. Submucosal invasion and piecemeal resection independently predicted R1 resections. A total of 18(5.5 %) intra-procedural AEs (perforation:11, bleeding:7) and 12(3.7 %) post-procedural AEs occurred (perforation:2, bleeding: 10). Eighteen adenoma recurrences per 1,000 person-years (15cases, 5.6 %) were detected after a median follow-up time of 36 months. All recurrences were detected within 12 months. No carcinoma recurrences were observed. R1 resection status and intra-procedural AEs independently predicted recurrences with seven vs 150 recurrences per 1,000 person-years in the R0 vs R1 group, respectively. Conclusions  Colorectal ESD is a safe and effective option for managing superficial colorectal neoplasia in a Western setting, with short and long-terms outcomes comparable to Eastern studies. En-bloc R0 resection and absence of intra-procedural AEs are associated with reduced risk of recurrence.

Risk Stratification of T1 Colorectal Cancer Metastasis to Lymph Nodes: Current Status and Perspective

With the widely spreading population-based screening programs for colorectal cancer and recent improvements in endoscopic diagnosis, the number of endoscopic resections in subjects with T1 colorectal cancer has been increasing. Some reports suggest that endoscopic resection prior to surgical resection of T1 colorectal cancer has no adverse effect on prognosis and contributes to this tendency. The decision on the need for surgical resection as an additional treatment after endoscopic resection of T1 colorectal cancer should be made according to the metastasis risk to lymph nodes based on histopathological findings. Because lymph node metastasis occurs in approximately 10% of patients with T1 colorectal cancer according to current international guidelines, the remaining 90% of patients may be at an increased risk of surgical resection and associated postoperative mortality, with no clinical benefit derived from unnecessary surgical resection. Although a more accurate prediction system for lymph node metastasis is needed to solve this problem, risk stratification for lymph node metastasis remains controversial. In this review, we focus on the current status of risk stratification of T1 colorectal cancer metastasis to lymph nodes and outline future perspectives.

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

BACKGROUND & AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Compound Endoscopic Morphological Features for Identifying Non-Pedunculated Lesions ≥20 mm with Intramucosal Neoplasia

BACKGROUND

The major limitation of piecemeal endoscopic mucosal resection (EMR) is the inaccurate histological assessment of the resected specimen, especially in cases of submucosal invasion.

OBJECTIVE

To classify non-pedunculated lesions ≥20 mm based on endoscopic morphological features, in order to identify those that present intramucosal neoplasia (includes low-grade neoplasia and high-grade neoplasia) and are suitable for piecemeal EMR.

DESIGN

A post-hoc analysis from an observational prospective multicentre study conducted by 58 endoscopists at 17 academic and community hospitals was performed. Unbiased conditional inference trees (CTREE) were fitted to analyse the association between intramucosal neoplasia and the lesions' endoscopic characteristics.

RESULT

542 lesions from 517 patients were included in the analysis. Intramucosal neoplasia was present in 484 of 542 (89.3%) lesions. A conditional inference tree including all lesions' characteristics assessed with white light imaging and narrow-band imaging (NBI) found that ulceration, pseudodepressed type and sessile morphology changed the accuracy for predicting intramucosal neoplasia. In ulcerated lesions, the probability of intramucosal neoplasia was 25% (95%CI: 8.3-52.6%; p < 0.001). In non-ulcerated lesions, its probability in lateral spreading lesions (LST) non-granular (NG) pseudodepressed-type lesions rose to 64.0% (95%CI: 42.6-81.3%; p < 0.001). Sessile morphology also raised the probability of intramucosal neoplasia to 86.3% (95%CI: 80.2-90.7%; p < 0.001). In the remaining 319 (58.9%) non-ulcerated lesions that were of the LST-granular (G) homogeneous type, LST-G nodular-mixed type, and LST-NG flat elevated morphology, the probability of intramucosal neoplasia was 96.2% (95%CI: 93.5-97.8%; p < 0.001).

CONCLUSION

Non-ulcerated LST-G type and LST-NG flat elevated lesions are the most common non-pedunculated lesions ≥20 mm and are associated with a high probability of intramucosal neoplasia. This means that they are good candidates for piecemeal EMR. In the remaining lesions, further diagnostic techniques like magnification or diagnostic +/- therapeutic endoscopic submucosal dissection should be considered.

A Surveillance Endoscopy Strategy Based on Local Recurrence Rates after Colorectal Endoscopic Submucosal Dissection

Backgrounds: It is not clear when and how frequently surveillance endoscopy should be performed after colorectal endoscopic submucosal dissection (ESD). We aimed to suggest a surveillance endoscopy strategy by investigating the cumulative local recurrence rates and identifying risk factors for local recurrence after colorectal ESD. Methods: We reviewed the medical records of 770 patients who underwent colorectal ESD for 778 lesions at our institution from 2005 to 2016. We investigated the cumulative local recurrence rates and risk factors for local recurrence. Results: Local recurrence developed in 12 (1.5%) of 778 lesions during the follow-up period of 37.4 ± 31.7 months. The one-, three-, and five-year cumulative local recurrence rates were 0.4%, 1.7%, and 2.2%, respectively. The risk factors for local recurrence were piecemeal resection (odds ratio (OR) 3.948, 95% confidence interval (CI) 1.164–13.385; p = 0.028) and histological incomplete resection (OR 8.713, 95% CI 2.588–29.334; p < 0.001). Local recurrence tended to develop frequently after ESD of early cancers. Conclusions: Short-term surveillance endoscopy should be recommended after piecemeal ESD, histological incomplete resection, and ESD of early colorectal cancers. Surveillance endoscopy with longer intervals can be suggested after en bloc ESD with the histological complete resection of benign colorectal tumors.

Current Endoscopic Resection Techniques for Gastrointestinal Lesions: Endoscopic Mucosal Resection, Submucosal Dissection, and Full-Thickness Resection

BACKGROUND

Endoscopic resection of dysplastic lesions in early stages of cancer reduces mortality rates and is recommended by many national guidelines throughout the world. Snare polypectomy and endoscopic mucosal resection (EMR) are established techniques of polyp removal. The advantages of these methods are their relatively short procedure times and acceptable complication rates. The latter include delayed bleeding in 0.9% and a perforation risk of 0.4-1.3%, depending on the size and location of the resected lesion. EMR is a recent modification of endoscopic resection. A limited number of studies suggest that larger lesions can be removed en bloc with low complication rates and short procedure times. Novel techniques such as endoscopic submucosal dissection (ESD) are used to enhance en bloc resection rates for larger, flat, or sessile lesions. Endoscopic full-thickness resection (EFTR) is employed for non-lifting lesions or those not easily amenable to resection. Procedures such as ESD or EFTR are emerging standards for lesions inaccessible to EMR techniques.

SUMMARY

Endoscopic treatment is now regarded as first-line therapy for benign lesions.

KEY MESSAGE

Endoscopic resection of dysplastic lesions or early stages of cancer is recommended. A plethora of different techniques can be used dependent on the lesions.

A Novel Self-Assembled Gel for Gastric Endoscopic Submucosal Dissection-Induced Ulcer: A Preclinical Study in a Porcine Model

Endoscopic submucosal dissection (ESD) is a routine procedure for the management of early gastrointestinal neoplasia, but it results in large ulcers. This study aims to examine the feasibility and effectiveness of a newly developed self-assembled gel on the ulcer healing process after ESD. Sixteen 2.0-cm (diameter) gastric ulcers were created by ESD in five pigs. All ulcers were randomized: control group (n = 7, routine ulcer management) and gel-treated group (n = 9). The gel was applied to cover the whole ulcer bed through the endoscope immediately after ESD. The feasibility of this endoscopic treatment modality was macroscopically accessed by endoscopy. The effectiveness was evaluated based on the ulcer area and histology changes at 14 days after ESD. The gel-treated group showed higher healing activity compared with the control ulcers on day 14 after ESD. The percentage of healing was higher for the gel-treated ulcers than in control ones (96.2 ± 2.2% vs. 91.9 ± 4.5%, p = 0.035). The extent of the new epithelium covering the ulcer was greater in the gel group than in controls. One delayed overt bleeding occurred in the control group (14.3%). This novel gel might promote the speed of ulcer healing after ESD, leading to higher epithelium formation.

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.

Blue laser imaging combined with JNET (Japan NBI Expert Team) classification for pathological prediction of colorectal laterally spreading tumors

BACKGROUND

Blue laser imaging (BLI) can provide useful information on colorectal laterally spreading tumors (LSTs) by visualizing the surface and vessel patterns in detail. The present research aimed to evaluate the diagnostic performance of BLI-combined JNET (Japan NBI Expert Team) classification for identifying LSTs.

METHODS

This retrospective, multicenter study included 172 LSTs consisted of 6 hyperplastic polyps/sessile serrated polyps, 94 low-grade dysplasias (LGD), 60 high-grade dysplasias (HGD), 6 superficial submucosal invasive (m-SMs) carcinomas, and 4 deep submucosal invasive carcinomas. The relationship between the JNET classification and the histologic findings of these lesions were then analyzed.

RESULTS

For all LSTs, non-experts and experts had a 79.7% and 90.7% accuracy for Type 2A (P = 0.004), a sensitivity of 94.7% and 96.8% (P = 0.718), and a specificity of 61.5% and 83.3% (P = 0.002) for prediction of LGD, respectively. The results also demonstrated 80.8% and 91.3% accuracy for Type 2B (P = 0.005), a sensitivity of 65.2% and 83.3% (P = 0.017), and a specificity of 90.6% and 96.2% (P = 0.097) for predicting HGD or m-SMs. For LST-granular (LST-G) lesions, Type 2A in experts had higher specificity (65.6% vs. 83.6%, P = 0.022) and accuracy (81.8% vs. 91.2%, P = 0.022). Type 2B in experts only had higher accuracy (82.5% vs. 92.0%, P = 0.019). However, no significant differences were noted for any comparisons between non-experts and experts for LST-non-granular (LST-NG) lesions.

CONCLUSIONS

BLI combined with JNET classification was an effective method for the precise prediction of pathological diagnosis in patients with LSTs. Diagnostic performance of JNET classification by experts was better than that by non-experts for all examined LST or LST-G lesions when delineating between Type 2A and 2B, but there was no difference for the identification of LST-NG lesions by these two groups.

Endoscopic characteristics influencing postpolypectomy bleeding in 1147 consecutive pedunculated colonic polyps: a multicenter retrospective study

BACKGROUND AND AIMS

Postpolypectomy bleeding is the most common adverse event with pedunculated polyps. We clarified the endoscopic characteristics influencing postpolypectomy bleeding for pedunculated colonic polyps.

METHODS

We reviewed clinical data for 1147 pedunculated colonic polyps removed by polypectomy in 5 Japanese institutions. Pedunculated polyps were defined as polyps with a stalk length ≥5 mm. Analyzed clinical data were age, sex, polyp location/size, stalk length/width, prophylactic clipping or endoloop before polypectomy, injecting the stalk, closing the polypectomy site, antithrombotic agent use, and endoscopist experience. Postpolypectomy bleeding was classified as immediate bleeding or delayed bleeding.

RESULTS

Immediate and delayed bleeding was observed in 8.5% (97/1147) and 2% (23/1147) of polypectomies, respectively. Comparing immediate bleeding with nonbleeding, multivariate analysis showed that stalk width ≥6 mm (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1-3.4) was a significant risk factor for immediate bleeding. For polyp size ≥15 mm, prophylactic endoloop use (OR, .17; 95% CI, .04-.72) was a significant inhibiting factor. Comparing delayed bleeding with nonbleeding, multivariate analysis showed that prophylactic clipping before polypectomy (OR, 4.2; 95% CI, 1.3-13) and injecting the stalk (OR, 4.0; 95% CI, 1.4-12) were significant risk factors for delayed bleeding.

CONCLUSIONS

The increased risk for delayed bleeding with injecting the stalk and prophylactic clipping before polypectomy suggests that simple resection with coagulation mode is a suitable strategy in endoscopic resection of pedunculated polyps. Moreover, prophylactic endoloop use was highly likely to inhibit immediate bleeding with polyp size ≥15 mm.

Endoscopic management of colorectal polyps: From benign to malignant polyps

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer related death in the world. The early detection and removal of CRC precursor lesions has been shown to reduce the incidence of CRC and cancer-related mortality. Endoscopic resection has become the first-line treatment for the removal of most precursor benign colorectal lesions and selected malignant polyps. Detailed lesion assessment is the first critical step in the evaluation and management of colorectal polyps. Polyp size, location and both macro- and micro- features provide important information regarding histological grade and endoscopic resectability. Benign polyps and even malignant polyps with superficial submucosal invasion and favorable histological features can be adequately removed endoscopically. When compared to surgery, endoscopic resection is associated with lower morbidity, mortality, and higher patient quality of life. Conversely, malignant polyps with deep submucosal invasion and/or high risk for lymph node metastasis will require surgery. From a practical standpoint, the most appropriate strategy for each patient will need to be individualized, based not only on polyp- and patient-related characteristics, but also on local resources and expertise availability. In this review, we provide a broad overview and present a potential decision tree algorithm for the evaluation and management of colorectal polyps that can be widely adopted into clinical practice.

Volume of surgical interventions for benign colorectal tumors – an analysis of 3510 surgical and endoscopic resections in the single colorectal center in Poland

Introduction: Colorectal cancer is the most frequent neoplasm of the whole gastrointestinal track. Due to screening colonoscopy program, colorectal lesions are often diagnosed at early stage. The vast majority of them are possible to remove endoscopically. However, a substantial percentage of benign lesion in Western centers are still operated. The aim of this article was to determine the percentage of surgical resections due to benign adenomas in the reference center of endoscopic submucosal dissection (ESD) and colorectal surgery in Poland. Materials and Methods: Retrospective analysis of 3 510 patients operated from 2015 to 2019 in Center of Bowel Treatment in Brzeziny. Results: We have analyzed 3 510 endoscopic and surgical procedures performed in the colon: 601 ESDs; 1 002 endoscopic mucosal resections (EMRs); and 1,907 surgical resections. Out of 601 ESDs, 57 invaded the submucosa, of which 29 (4.8%) were non-therapeutic ESDs. In 5 patients, due to occurrence of post-ESD perforation, an additional surgical intervention was necessary. Out of the 1,002 EMRs, 22 cases (2.2%) were diagnosed with deeply infiltrating cancers, which required a surgery. The overall percentage of the need for surgery in the endoscopically treated patients (ESD + mucosectomy) was 3.5% (56/1 603). Among resection surgeries, 15 of them (0.8%) ended with the diagnosis of a benign lesion in the postoperative histopathological examination. Conclusions: Inclusion advanced endoscopic techniques such as ESD to routine clinical practice in colorectal centers gives clear benefits for the patients. Well defined and standardized process of qualifying for appropriate treatment allows to significantly reduce the percentage of abdominal approach surgery due to benign colorectal lesions.  

Efficacy and histologic accuracy of underwater versus conventional endoscopic mucosal resection for large (>20 mm) colorectal polyps: a comparative review and meta-analysis

BACKGROUND AND AIMS

Major limitations with conventional EMR (C-EMR) include high rates of polyp recurrence and low en-bloc resection rates, especially for lesions >20 mm in size. Underwater EMR (U-EMR) has emerged as an alternate technique for en-bloc resection of larger lesions. We conducted a systematic review and meta-analysis comparing the efficacy and safety of the 2 techniques.

METHODS

Multiple databases were searched through June 2020 for studies that compared outcomes of U-EMR and C-EMR for colorectal lesions. Meta-analysis was performed to determine pooled odds ratios (ORs) of successful R0, en-bloc, and piecemeal resection of colorectal lesions. We compared the rates of polyp recurrence at follow-up, diagnostic accuracy for colorectal cancer, and adverse events with the 2 techniques.

RESULTS

Eleven studies, including 4 randomized controlled trials (RCTs) with 1851 patients were included in the final analysis. A total of 1071 lesions were removed using U-EMR, and 1049 lesions were removed using C-EMR. Although U-EMR had an overall superior en-bloc resection rate compared with C-EMR (OR, 1.9; 95% confidence interval [CI], 1-3.5; P = .04), both techniques were comparable in terms of polyps >20 mm in size (OR, 0.8; 95% CI, 0.3-2.1; P = .75), R0 resection (OR, 3.1; 95% CI, 0.74-12.6; P = .14), piecemeal resection (OR, 3.1; 95% CI, 0.74-12.6; P = .13), and diagnostic accuracy for colorectal cancer (OR, 1.1; 95% CI, 0.6-1.8; P = .82). There were lower rates of polyp recurrence (OR, 0.3; 95% CI, 0.1-0.8; P = .01) and incomplete resection (OR, 0.4; 95% CI, 0.2-0.5; P = .001) with U-EMR. Both techniques have comparable resection times and safety profiles.

CONCLUSIONS

Our results support the use of U-EMR over C-EMR for successful resection of colorectal lesions. Further randomized controlled trials are needed to evaluate the efficacy of U-EMR for resecting polyps >20 mm in size.

Artificial intelligence-enhanced white-light colonoscopy with attention guidance predicts colorectal cancer invasion depth

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) and EMR are applied in treating superficial colorectal neoplasms but are contraindicated by deeply invasive colorectal cancer (CRC). The invasion depth of neoplasms can be examined by an automated artificial intelligence (AI) system to determine the applicability of ESD and EMR.

METHODS

A deep convolutional neural network with a tumor localization branch to guide invasion depth classification was constructed on the GoogLeNet architecture. The model was trained using 7734 nonmagnified white-light colonoscopy (WLC) images supplemented by image augmentation from 657 lesions labeled with histopathologic analysis of invasion depth. An independent testing dataset consisting of 1634 WLC images from 156 lesions was used to validate the model.

RESULTS

For predicting noninvasive and superficially invasive neoplasms, the model achieved an overall accuracy of 91.1% (95% confidence interval [CI], 89.6%-92.4%), with 91.2% sensitivity (95% CI, 88.8%-93.3%) and 91.0% specificity (95% CI, 89.0%-92.7%) at an optimal cutoff of .41 and the area under the receiver operating characteristic (AUROC) curve of .970 (95% CI, .962-.978). Inclusion of the advanced CRC data significantly increased the sensitivity in differentiating superficial neoplasms from deeply invasive early CRC to 65.3% (95% CI, 61.9%-68.8%) with an AUROC curve of .729 (95% CI, .699-.759), similar to experienced endoscopists (.691; 95% CI, .624-.758).

CONCLUSIONS

We have developed an AI-enhanced attention-guided WLC system that differentiates noninvasive or superficially submucosal invasive neoplasms from deeply invasive CRC with high accuracy, sensitivity, and specificity.

Very low rate of residual neoplasia after non-curative endoscopic submucosal dissection: a western single-center experience

BACKGROUND

Short and long outcomes of endoscopic submucosal dissection (ESD) are now well described. However, the outcome of non-curative ESDs is scarcely reported.

OBJECTIVE

To describe our experience with non-curative ESDs, assessing the presence of residual lesion in the endoscopic follow-up or surgery.

METHODS

Data of all the patients submitted to ESD between January 2015 and June 2020 in our tertiary Center was prospectively recorded. Among non-curative ESDs, the presence of residual neoplasia after complementary surgical treatment or in the endoscopic follow-up was assessed.

RESULTS

In that period, a total of 388 ESDs were performed in the esophagus (n = 13), stomach (n = 222), colon (n = 20), rectum (n = 132), and duodenum (n = 1). Median follow-up was 30 months (range 4-69 months). ESD was technically successful in 376 lesions (97%). From 325 neoplastic epithelial lesions and 18 neoplastic submucosal tumors, 61 (17.8%) did not fulfill curative criteria entirely. Positive horizontal margins (n = 28), positive vertical margins (n = 10) and submucosal invasion >SM1 (n = 14) were the main causes of non-curative ESD. Among patients with non-curative ESDs, 20 were operated and 33 were already followed-up by endoscopy, and only seven (13%, corresponding to 2% of the total number of successful neoplastic ESDs) had residual neoplasia.

CONCLUSION

Our real-life experience showed that the vast majority of non-curative ESD did not actually have residual neoplasia in the follow-up.

Indications and outcomes of endoscopic resection for non-pedunculated colorectal lesions: A narrative review

In the last years, endoscopic techniques gained a crucial role in the treatment of colorectal flat lesions. At the same time, the importance of a reliable assessment of such lesions to predict the malignancy and the depth of invasion of the colonic wall emerged. The current unsolved dilemma about the endoscopic excision techniques concerns the necessity of a reliable submucosal invasive cancer assessment system that can stratify the risk of the post-procedural need for surgery. Accordingly, this narrative literature review aims to compare the available diagnostic strategies in predicting malignancy and to give a guide about the best techniques to employ. We performed a literature search using electronic databases (MEDLINE/PubMed, EMBASE, and Cochrane Library). We collected all articles about endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) registering the outcomes. Moreover, we analyzed all meta-analyses comparing EMR vs ESD outcomes for colorectal sessile or non-polypoid lesions of any size, preoperatively estimated as non-invasive. Seven meta-analysis studies, mainly Eastern, were included in the analysis comparing 124 studies and overall 22954 patients who underwent EMR and ESD procedures. Of these, eighty-two were retrospective, twenty-four perspective, nine case-control, and six cohorts, while three were randomized clinical trials. A total of 18118 EMR and 10379 ESD were completed for a whole of 28497 colorectal sessile or non-polypoid lesions > 5-10 mm in size. In conclusion, it is crucial to enhance the preoperative diagnostic workup, especially in deciding the most suitable endoscopic method for radical resection of flat colorectal lesions at risk of underlying malignancy. Additionally, the ESD necessitates further improvement because of the excessively time-consuming as well as the intraprocedural technical hindrances and related complications. We found a higher rate of en bloc resections and R0 for ESD than EMR for non-pedunculated colorectal lesions. Nevertheless, despite the lower local recurrence rates, ESD had greater perforation rates and needed lengthier procedural times. The prevailing risk for additional surgery in ESD rather than EMR for complications or oncologic reasons is still uncertain.

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.