EMR of large sessile colorectal polyps

Outcomes of underwater endoscopic mucosal resection for colorectal polyps-Insights from western India

INTRODUCTION

Underwater endoscopic mucosal resection (uEMR) represents an alternative to conventional EMR for resection of sessile colorectal polyps. We aimed at assessing the efficacy and safety of uEMR for sessile colorectal polyps.

METHODS

A retrospective analysis of endoscopy database was done for patients who underwent uEMR for sessile colorectal polyps more than 10 mm in size without any features of sub-mucosal invasion from two tertiary care centres in western India between January 2021 and June 2023. Exclusion criteria were other modes of endoscopic resection. Primary outcome was rate of en bloc resection. Secondary outcomes were complete resection rate, adverse events and recurrence rate.

RESULTS

During the study period, 159 patients with 261 lesions met the study inclusion. Mean lesion size was 1.935 ± 0.71 cm with most lesion located in the rectum (75, 28.73%) followed by sigmoid colon (69, 26.43%). Most lesions had a Paris 0-Is morphology (192, 73.56%). Japan NBI Expert Team (JNET) IIa pattern was seen on narrow band imaging (NBI) in 221 (84.67%) lesions. Complete resection was achieved in 98.46% lesions (257/261). En bloc resection was achieved in 91.82% (236/257) lesions. Complications were seen in 6.8%, all of which were managed endoscopically. Recurrence was seen in 3.1% of polyps on follow-up.

CONCLUSION

uEMR is a safe and efficacious technique for endoscopic resection for sessile colorectal polyps with high rates of en bloc resection for polyps more than 10 mm size.

Experience, Outcomes, and Insights on Endoscopic Colonic Polyp Excision: A Retrospective Cohort Study

Introduction Colorectal cancer (CRC) continues to pose a major public health challenge, ranking among the most common malignancies globally and being a leading cause of cancer-related mortality. Most CRCs originate from adenomatous polyps, underscoring the importance of detecting and removing these precancerous growths as a key preventive measure against CRC. In particular, large colonic polyps (≥10 mm) warrant special attention due to their increased risk of progressing to malignancy compared to smaller polyps. This retrospective study aims to evaluate the outcomes of large polyp excision within a single NHS trust. By analysing patient demographics, polyp characteristics, procedural details, and clinical outcomes, this study seeks to provide comprehensive data on the efficacy and safety of endoscopic polyp excision. Patients and methods This retrospective cohort study was conducted at Maidstone and Tunbridge Wells NHS Trust, a district general hospital in Tunbridge Wells, England, with data collected for all patients who had endoscopic polypectomy from 2010 to 2022. Data collected from medical records included age, sex, polyp size and characteristics, and previous polyp removal attempts. Results A total of 350 participants were included in this study. The cohort comprised 224 males (64%) and 126 females (36%), with a mean age of 70 ± 12 years. Complications were observed in eight participants (2.3%), while 340 participants (97.7%) did not experience any complications. Participants who experienced complications had a mean polyp size of 49.38 ± 7.3 mm, whereas those without complications had a mean polyp size of 44.85 ± 16.5 mm (p = 0.440). All complications occurred in participants with polyps ≥40 mm. However, this association was not statistically significant (p = 0.352). Conclusion Our study has shown that large polyps can be safely excised in a local district hospital. The incidence of complications is related to the polyp size. A cutoff size of 40 mm was found to be related to increased complications. However, this was still statistically insignificant and won't affect the efficacy and safety of these procedures being carried out in a local district hospital, decreasing the load on tertiary and specialised hospitals.

Endoscopic Resection of Neoplasia in the Lower GI Tract: A Clinical Algorithm

Background

Colorectal cancer is a highly prevalent malignancy and a significant driver of cancer mortality and health-related expenditure worldwide. Polyp removal reduces the incidence and mortality of colorectal cancer. In 2024, endoscopists have an array of resection modalities at their disposal. Each technique requires a unique skillset and has individual advantages and limitations. Consequently, resection in the colorectum requires an evidence-based algorithm approach that considers these factors.

Summary

A literature review of endoscopic resection for colonic neoplasia was conducted. Best supporting scientific evidence was summarized for the endoscopic resection of diminutive polyps, large ≥20 mm lesions and polyps containing invasive cancer. Factors including resection modality, complications and lesion selection were explored to inform an algorithm approach to colorectal resection.

Key Messages

Endoscopic resection in the colorectum is not a one-size-fits-all approach. Detailed understanding of polyp size, location, morphology and predicted histology are critical factors that inform appropriate endoscopic resection practice.

Characteristics of positive horizontal margins in patients who underwent colorectal endoscopic submucosal dissection

Objectives

Endoscopic submucosal dissection (ESD) enables en bloc resection of colorectal neoplasms, but occasionally results in positive horizontal margins (HMs). However, the site of the resected specimen that tends to be positive for HM has not been investigated. We aimed to clarify the characteristics associated with HMs in lesions resected en bloc with ESD.

Methods

Patients with colorectal neoplasms who underwent en bloc resection with ESD were included in this study. The patients were divided into negative HMs (HM0) and positive or indeterminate HMs (HM1) groups. The characteristics associated with HM1 resection were investigated. In addition, the local recurrence rate during endoscopic follow-up for >6 months after ESD was observed.

Results

In total, 201 lesions were analyzed in 189 patients (HM0, 189 lesions; HM1, 12 lesions). The HM1 group had a significantly larger median lesion diameter (25 vs. 55 mm; p < 0.001) and more lesions with >50% circumference than did the HM0 group (p < 0.001). Furthermore, the prevalence of severe fibrosis was significantly higher in the HM1 group than in the HM0 group (p < 0.001). Positive horizontal sites of the resected specimens were more frequent at the oral and anal sites than at the lateral sites. No local recurrences were observed in either group.

Conclusions

The characteristics associated with HM1 depended on lesion size, particularly lesions with >50% circumference, and submucosal fibrosis.

Endoscopic resection of large non-pedunculated colorectal polyps: current standards of treatment

Colorectal cancer is a significant public health concern, and large non-pedunculated colorectal polyps pose a substantial risk for malignancy and incomplete resection, which may lead to interval cancer. The choice of resection technique is influenced by various factors, including polyp size, morphology, location, submucosal invasion depth and endoscopist expertise. For non-cancerous superficial large non-pedunculated polyps, conventional hot or cold snare polypectomy, endoscopic mucosal resection and endoscopic submucosal dissection are common techniques for non-surgical therapeutic endoscopic resection of these polyps. This manuscript provides a comprehensive review of literature on current endoscopic resection techniques for large non-pedunculated colorectal polyps, emphasising indications, advantages, limitations and outcomes.

Endoscopic mucosal resection-precutting vs conventional endoscopic mucosal resection for sessile colorectal polyps sized 10-20 mm

BACKGROUND

The optimal method to remove sessile colorectal lesions sized 10-20 mm remains uncertain. Piecemeal and incomplete resection are major limitations in current practice, such as endoscopic mucosal resection (EMR) and cold or hot snare polypectomy. Recently, EMR with circumferential precutting (EMR-P) has emerged as an effective technique, but the quality of current evidence in comparative studies of conventional EMR (CEMR) and EMR-P is limited.

AIM

To investigate whether EMR-P is superior to CEMR in removing sessile colorectal polyps.

METHODS

This multicenter randomized controlled trial involved seven medical institutions in China. Patients with colorectal polyps sized 10-20 mm were enrolled and randomly assigned to undergo EMR-P or CEMR. EMR-P was performed following submucosal injection, and a circumferential mucosa incision (precutting) was conducted using a snare tip. Primary outcomes included a comparison of the rates of en bloc and R0 resection, defined as one-piece resection and one-piece resection with histologically assessed clear margins, respectively.

RESULTS

A total of 110 patients in the EMR-P group and 110 patients in the CEMR group were finally evaluated. In the per-protocol analysis, the proportion of en bloc resections was 94.3% [95% confidence interval (CI): 88.2%-97.4%] in the EMR-P group and 86% (95%CI: 78.2%-91.3%) in the CEMR group (P = 0.041), while subgroup analysis showed that for lesions > 15 mm, EMR-P also resulted in a higher en bloc resection rate (92.0% vs 58.8% P = 0.029). The proportion of R0 resections was 81.1% (95%CI: 72.6%-87.4%) in the EMR-P group and 76.6% (95%CI: 68.8%-84.4%) in the CEMR group (P = 0.521). The EMR-P group showed a longer median procedure time (6.4 vs 3.0 min; P < 0.001). No significant difference was found in the proportion of patients with adverse events (EMR-P: 9.1%; CEMR: 6.4%; P = 0.449).

CONCLUSION

In this study, EMR-P served as an alternative to CEMR for removing nonpedunculated colorectal polyps sized 10-20 mm, particularly polyps > 15 mm in diameter, with higher R0 and en bloc resection rates and without increasing adverse events. However, EMR-P required a relatively longer procedure time than CEMR. Considering its potential benefits for en bloc and R0 resection, EMR-P may be a promising technique in colorectal polyp resection.

Efficacy and Safety of Endoscopic Mucosal Resection with the Two-Person Method

Objectives Endoscopic mucosal resection (EMR) is useful for removing colon polyps and is generally carried out by one doctor. It is occasionally difficult for colorectal polyps to be removed by EMR. In such cases, EMR is performed by the main doctor and an assistant doctor (the two-person method). However, the efficacy and safety of EMR in the two-person method remain unclear. This study aimed to compare the procedure time and incomplete resection rate (IRR) by the two- and single-person methods of EMR for polyp removal.

Materials and Methods Data from colorectal polyps resected by EMR were reviewed retrospectively and divided into two groups: general procedure/single- (n = 215) or two-person method (n = 56). The IRR, the procedure time, and the incidence of adverse events were compared between these methods.

Results A total of 152 patients and 271 lesions were included in this study. The mean procedure time for polypectomy was significantly shorter in the two-person method group than in the general procedure group (median time: 3.38 minutes vs. 6.56 minutes; p < 0.001). Additionally, the IRR for polyps was significantly lower in the two-person methods group than in the single-person methods group (2/56, 3.6% vs. 47/215, 21.9%; p = 0.001). None of the patients in the two-person method group presented with delayed bleeding.

Conclusions The two-person method for EMR was more effective than the single-person method. Therefore, this method may replace the conventional one-operator method in the future.

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.

Depth of the cutting plane with underwater and conventional endoscopic mucosal resection: Post-hoc analysis of a randomized study

BACKGROUND AND AIM

A multicenter randomized controlled trial reported a better R0 resection rate for intermediate-sized (10-20 mm) colorectal polyps with underwater endoscopic mucosal resection (UEMR) than conventional endoscopic mucosal resection (CEMR). To clarify whether UEMR removes enough submucosal tissue in the removal of unpredictable invasive cancers, we investigated the cutting plane depth with UEMR versus CEMR.

METHODS

This was a post-hoc analysis of a randomized controlled trial in which 210 intermediate-sized colorectal polyps were removed in five Japanese hospitals. One pathologist and two gastroenterologists independently reviewed all resected specimens and measured the cutting plane depth. The cutting plane depth was evaluated as (i) maximum depth of submucosal layer and (ii) mean depth of submucosal layer, calculated using a virtual pathology system.

RESULTS

We identified 168 appropriate specimens for the evaluation of the cutting plane depth, resected by UEMR (n = 88) and CEMR (n = 80). The median resection depth was not significantly different between UEMR and CEMR specimens, regardless of the measurement method ([i] 1317 vs 1290 μm, P = 0.52; [ii] 619 vs 545 μm, P = 0.32). All specimens in the UEMR and CEMR groups contained substantial submucosa and no muscularis propria.

CONCLUSIONS

The cutting plane depth with UEMR was comparable with that with CEMR. UEMR can be a viable alternative method that adequately resects the submucosal layer for the histopathological assessment of unpredictable submucosal invasive cancers.

Risk Stratification of Endoscopic Submucosal Dissection in Colon Tumors

Background: Endoscopic submucosal dissection (ESD) is a technique proven effective in the treatment of early neoplastic lesions in the gastrointestinal tract. However, in the case of colon lesions, many doubts remain. The purpose of our study is to stratify the success rates of the ESD procedure in the colon. Materials and Methods: A retrospective analysis of 601 patients who underwent ESD procedure for colorectal neoplasm from 2016 to 2019 in Center of Bowel Treatment, Brzeziny, Poland. Excluding 335 rectal neoplasms, we selected 266 patients with lesions located in the colon. Results: Lesions located in the left colon were characterized by the statistically higher en bloc resection and success rate, compared with the right colon—87.76% vs. 73.95% (p = 0.004) and 83.67% vs. 69.75% (p = 0.007), respectively. The success rate was significantly lower in lesions with submucosal cancer, compared to low- and high-grade dysplasia (p < 0.001). Polyps located in the right colon were characterized by a slightly higher complication rate compared to the left colon, without statistical significance—13.45% vs. 9.52% (p = 0.315). Conclusions: Our results show that colonic ESD has a high success rate, especially in the left colon, with a low risk of complications, slightly higher than in the right colon.

Colonoscopic-Assisted Laparoscopic Wedge Resection for Colonic Lesions: A Prospective Multicentre Cohort Study (LIMERIC-Study)

OBJECTIVE

The aim of this study was to evaluate the safety and efficacy of a modified colonoscopic-assisted laparoscopic wedge resection.

SUMMARY BACKGROUND DATA

The use of segmental colectomy in patients with endoscopically unresectable colonic lesions results in significant morbidity and mortality. CAL-WR is an alternative procedure that may reduce morbidity.

METHODS

This prospective multicentre study was performed in 13 Dutch hospitals between January 2017 and December 2019. Inclusion criteria were (1) colonic lesions inaccessible using current endoscopic resection techniques (judged by an expert panel), (2) non-lifting residual/recurrent adenomatous tissue after previous polypectomy or (3) an undetermined resection margin after endoscopic removal of a low-risk pT1 colon carcinoma. Thirty-day morbidity, technical success rate and radicality were evaluated.

RESULTS

Of the 118 patients included (56% male, mean age 66 years, SD ± 8 years), 66 (56%) had complex lesions unsuitable for endoscopic removal, 34 (29%) had non-lifting residual/recurrent adenoma after previous polypectomy and 18 (15%) had uncertain resection margins after polypectomy of a pT1 colon carcinoma. CAL-WR was technically successful in 93% and R0 resection was achieved in 91% of patients. Minor complications (Clavien-Dindo I-II) were noted in 7 patients (6%) and an additional oncologic segmental resection was performed in 12 cases (11%). Residual tissue at the scar was observed in 5% of patients during endoscopic follow-up.

CONCLUSIONS

CAL-WR is an effective, organ-preserving approach that results in minor complications and circumvents the need for major surgery. CAL-WR therefore deserves consideration when endoscopic excision of circumscribed lesions is impossible or incomplete.

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.

Snare tip soft coagulation (STSC) after endoscopic mucosal resection (EMR) of large (> 20 mm) non pedunculated colorectal polyps: a systematic review and meta-analysis

Background and study aims  Endoscopic mucosal resection (EMR) of laterally spreading tumors (LSTs) > 20 mm in size can be challenging. Piecemeal EMR of these lesions results in high rates of adenoma recurrence at first surveillance colonoscopy (SC1). Snare tip soft coagulation (STSC) of post resection margins is a safe and effective technique to prevent adenoma recurrence. We conducted a systematic review and meta-analysis to evaluate the effectiveness and safety of this technique. Patients and methods  Multiple databases were searched through April 2021 for studies that reported on outcomes of post EMR STSC for LSTs > 20 mm in size. Meta-analysis was performed to determine pooled odds of adenoma recurrence as well as pooled proportion of adverse events including intraprocedural and delayed bleeding as well as intraprocedural perforation events. Results  Six studies including two randomized controlled trials (RCT) and four cohort studies with 2122 patients were included in the final analysis. Overall pooled odds of adenoma recurrence at SC1 with post EMR STSC compared to no STSC was 0.27 (95 % 0.18-0.42; I2 = 0 %), P < 0.001. Pooled rate of adenoma recurrence at SC1 in post EMR STSC cohort was 6 %. Rates of intraprocedural bleeding, delayed bleeding and intraprocedural perforation were 10.3 %, 6.5 % and 2 % respectively. Conclusions  Our results show that thermal ablation of resection margins with STSC in LSTs > 20 mm is a safe and effective technique in reducing the incidence of adenoma recurrence.

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.

Child-Pugh B or C Cirrhosis Increases the Risk for Bleeding Following Colonoscopic Polypectomy

Background/Aims

The risk for colonoscopic postpolypectomy bleeding (PPB) in patients with chronic liver disease (CLD) remains unclear. We determined the incidence and risk factors for colonoscopic PPB in patients with CLD, especially those with liver cirrhosis.

Methods

We retrospectively reviewed the medical records of patients with CLD who underwent colonoscopic polypectomy at Seoul National University Hospital between 2011 and 2014. The study endpoints were immediate and delayed PPB.

Results

A total of 1,267 consecutive patients with CLD were included in the study. Immediate PPB occurred significantly more often in the Child-Pugh (CP) B or C cirrhosis group (17.5%) than in the CP-A (6.3%) and chronic hepatitis (4.6%) groups (p<0.001). Moreover, the incidence of delayed PPB in the CP-B or C cirrhosis group (4.4%) was significantly higher than that in the CP-A (0.7%) and chronic hepatitis (0.2%) groups (p<0.001). The independent risk factors for immediate PPB were CP-B or C cirrhosis (p=0.011), a platelet count <50,000/μL (p<0.001), 3 or more polyps (p=0.017), endoscopic mucosal resection or submucosal dissection (p<0.001), and polypectomy performed by trainees (p<0.001). The independent risk factors for delayed PPB were CP-B or C cirrhosis (p=0.009), and polyps >10 mm in size (p=0.010).

Conclusions

Patients with CP-B or C cirrhosis had an increased risk for bleeding following colonoscopic polypectomy.

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.

Underwater endoscopic mucosal resection of adenomas and colorectal serrated lesions: a prospective clinical study

Background

Underwater endoscopic mucosal resection (UEMR) without submucosal injection has been described as an alternative technique to the endoscopic resection of adenomas and colorectal serrated lesions. We aimed to assess the feasibility, safety, and efficacy of UEMR in a Brazilian setting.

Methods

This was a prospective observational study of consecutive patients who underwent UEMR between January and July 2019, in a single tertiary care center. Inclusion criteria were lesions without endoscopic stigmata of deep submucosal invasion in patients referred for endoscopic resection of colorectal adenomas, and serrated lesions detected in a previous colonoscopy. The following features were assessed: complete resection rate, en bloc resection rate, resection time, adverse events, and resection infeasibility.

Results

A total of 36 patients underwent UEMR for 51 colorectal lesions. The mean/median lesion size was 16.24/13 mm and the mean/median resection time was 16.97/9.19 min. Histopathology revealed the following: tubular adenoma (43.1%), tubulovillous adenoma (13.7%), serrated lesions (41.2%), and intramucosal adenocarcinoma (2%). Complete resection was achieved in 86.3% of cases; 52.9% of the lesions were removed en bloc, while 47.1% were resected in a piecemeal fashion. UEMR was feasible in 96.1% of cases and failed on 2 occasions, requiring conversion to standard endoscopic mucosal resection. Minor intraoperative bleeding occurred in 5 patients (9.8%) and only 1 presented with delayed bleeding (2%), all controlled endoscopically.

Conclusion

UEMR for removal of adenomas and colorectal serrated lesions was demonstrated to be feasible, safe and effective.

Colon mucosal neoplasia referred for endoscopic mucosal resection: Recurrence of adenomas and prediction of submucosal invasion

BACKGROUND

Endoscopic mucosal resection (EMR) is an effective and minimally invasive alternative to surgery for large polyps and laterally spreading lesions. Gross morphology and surface characteristics may help predict submucosal invasion of the lesion (SMIL) during endoscopic evaluation. This is one of the largest single-center studies reporting endoscopic mucosal resection for larger (≥ 20 mm) colorectal lesions in the United States.

AIM

To determine the recurrence rate of adenomas and endoscopic features that may predict submucosal invasion of colonic mucosal neoplasia.

METHODS

This is a retrospective cohort study of all the patients referred for endoscopic mucosal resection for lesions ≥ 20 mm, spanning a period from January 2013 to February 2017. The main outcome measure was identifying features that may predict submucosal invasion of mucosal lesions and predict recurrence of adenomas on follow-up surveillance colonoscopy performed at 4-6 mo.

RESULTS

A total of 480 patients with 500 lesions were included in the study. The median age was 68 (Inter quantile range: 14) with 52% males. The most common lesion location was ascending colon (161; 32%). Paris classification 0-IIa (Flat elevation of mucosa - 316; 63.2%); Kudo Pit Pattern IIIs (192; 38%) and Granular surface morphology (260; 52%) were most prevalent. Submucosal invasion was present in 23 (4.6%) out of 500 lesions. The independent risk factors for SMIL were Kudo Pit Pattern IIIL + IV and V (Odds ratio: 4.5; P value < 0.004) and Paris classification 0-IIc (Odds ratio: 18.2; P value < 0.01). Out of 500, 354 post-endoscopic mucosal resection scars were examined at surveillance colonoscopy. Recurrence was noted in 21.8% (77 cases).

CONCLUSION

There was overall low prevalence of SMIL in our study. Kudo pit pattern (IIIL + IV and V) and Paris classification 0-IIc were the only factors identified as an independent risk factor for submucosal invasion. The independent risk factor for recurrence was adenoma size (> 40 mm). Almost all recurrences (98.8%) were treated endoscopically.

UNDERWATER ENDOSCOPIC MUCOSAL RESECTION FOR NON-PEDUNCULATED COLORECTAL LESIONS. A PROSPECTIVE SINGLE-ARM STUDY

BACKGROUND

Underwater endoscopic mucosal resection (UEMR) has emerged as a revolutionary method allowing resection of colorectal lesions without submucosal injection. Brazilian literature about this technique is sparse.

OBJECTIVE

The aim of this study was evaluate the efficacy and safety of UEMR technique for removing non-pedunculated colorectal lesions in two Brazilian tertiary centers.

METHODS

This prospective study was conducted between June 2016 and May 2017. Naïve and non-pedunculated lesions without signs of submucosal invasion were resected using UEMR technique.

RESULTS

A total of 55 patients with 65 lesions were included. All lesions, except one, were successfully and completely removed by UEMR (success rate 98.5%). During UEMR, two cases of bleeding were observed (3.0%). One patient had abdominal pain on the day after resection without pneumoperitoneum. There was no perforation or delayed bleeding.

CONCLUSION

This study supports the existing data indicating acceptable rates of technical success, and low incidence of adverse events with UEMR. The results of this Brazilian study were consistent with previous abroad studies.

Impact of observational training on endoscopic mucosal resection outcomes and competency for large colorectal polyps: single endoscopist experience

Background and study aims  Endoscopic mucosal resection (EMR) is standard treatment for large colorectal polyps. However, it is a specialized technique with limited data on the effectiveness of training methods to acquire this skill. The aim of this study was to evaluate the impact of observational training on EMR outcomes and competency in an early-stage endoscopist. Patients and methods  A single endoscopist completed comprehensive EMR training, which included knowledge acquisition and direct observation of EMR cases, and proctored supervision, during the third year of gastroenterology fellowship. After training, EMR was independently attempted on 142 consecutive, large (i. e., ≥ 20 mm), non-pedunculated colorectal polyps between July 2014 and December 2017 (mean age 61.7 years; mean polyp size 30.4 mm; en-bloc resection 55 %). Surveillance colonoscopy for evaluation of residual neoplasia was available for 86 % of the cases. Three primary outcomes were evaluated: endoscopic assessment of complete resection, rate of adverse events (AEs), and rate of residual neoplasia on surveillance colonoscopy. Results  Complete endoscopic resection was achieved in 93 % of cases, the rates of AEs and residual neoplasia were 7.8 % and 7.3 %, respectively. The rate of complete resection remained stable (at 85 % or greater) with increasing experience while rates of AEs and residual neoplasia peaked and decreased after 60 cases. Conclusions  An early-stage endoscopist can acquire the skills to perform effective EMR after completing observational training. At least 60 independent EMRs for large colorectal polyps were required to achieve a plateau for clinically meaningful outcomes.

Multicenter Study of the Hemorrhage Risk after Endoscopic Mucosal Resection Associated with Direct Oral Anticoagulants

BACKGROUNDS AND AIMS

Recently, direct oral anticoagulants (DOACs) have become widely used for preventing thromboembolism. However, postoperative hemorrhage (POH) is a major complication associated with endoscopic mucosal resection (EMR) for colorectal lesions. In this multicenter study, we analyzed the incidence of POH after EMR associated with DOACs and explored the associated risk factors.

MATERIALS AND METHODS

This study was a multicenter retrospective cohort study conducted at 8 Japanese institutions. A total of 2062 cases that underwent EMR for colorectal lesions at these 8 institutions from October 2016 to September 2017 were analyzed. The cases were divided into 4 groups: the DOAC group (63 cases), warfarin group (34 cases), antiplatelet group (185 cases), and no antithrombotics group (1780 cases). In all lesions of the DOAC and warfarin groups, endoscopic clipping was performed after EMR. The rate of POH in the DOAC group, patients' clinical characteristics, the risk factors of POH, and the rate of thromboembolism due to stopping DOACs were compared with other groups.

RESULTS

The rates of POH were 7.9%∗ (5/63), 2.9% (1/34), 3.2% (6/185), and 0.6%∗∗ (11/1780) in the DOAC, warfarin, antiplatelet, and no antithrombotics groups, respectively (∗ vs. ∗∗, p < 0.001). Regarding risk factors, the tumor size with POH (mm) was significantly bigger than that without POH (16.2 ± 8.3 vs. 7.2 ± 4.9, p < 0.001). There were no significant differences in the rates of POH based on the type of DOAC. In addition, no thromboembolisms occurred due to stopping of DOAC treatment.

CONCLUSIONS

Patients receiving DOACs had significantly higher rates of POH after EMR than those without antithrombotics.

Clip Closure Prevents Bleeding After Endoscopic Resection of Large Colon Polyps in a Randomized Trial

BACKGROUND & AIMS

Bleeding is the most common severe complication after endoscopic mucosal resection of large colon polyps and is associated with significant morbidity and cost. We examined whether prophylactic closure of the mucosal defect with hemoclips after polyp resection reduces the risk of bleeding.

METHODS

We performed a multicenter, randomized trial of patients with a large nonpedunculated colon polyp (≥20 mm) at 18 medical centers in North America and Spain from April 2013 through October 2017. Patients were randomly assigned to groups that underwent endoscopic closure with a clip (clip group) or no closure (control group) and followed. The primary outcome, postprocedure bleeding, was defined as a severe bleeding event that required hospitalization, a blood transfusion, colonoscopy, surgery, or another invasive intervention within 30 days after completion of the colonoscopy. Subgroup analyses included postprocedure bleeding with polyp location, polyp size, or use of periprocedural antithrombotic medications. We also examined the risk of any serious adverse event.

RESULTS

A total of 919 patients were randomly assigned to groups and completed follow-up. Postprocedure bleeding occurred in 3.5% of patients in the clip group and 7.1% in the control group (absolute risk difference [ARD] 3.6%; 95% confidence interval [CI] 0.7%-6.5%). Among 615 patients (66.9%) with a proximal large polyp, the risk of bleeding in the clip group was 3.3% and in the control group was 9.6% (ARD 6.3%; 95% CI 2.5%-10.1%); among patients with a distal large polyp, the risks were 4.0% in the clip group and 1.4% in the control group (ARD -2.6%; 95% CI -6.3% to -1.1%). The effect of clip closure was independent of antithrombotic medications or polyp size. Serious adverse events occurred in 4.8% of patients in the clip group and 9.5% of patients in the control group (ARD 4.6%; 95% CI 1.3%-8.0%).

CONCLUSIONS

In a randomized trial, we found that endoscopic clip closure of the mucosal defect following resection of large colon polyps reduces risk of postprocedure bleeding. The protective effect appeared to be restricted to large polyps located in the proximal colon. ClinicalTrials.gov no: NCT01936948.

Cold snare endoscopic resection of nonpedunculated colorectal polyps larger than 10 mm: a systematic review and pooled-analysis

BACKGROUND AND AIMS

Hot snare polypectomy and EMR are the standard of care in resecting colorectal polyps ≥10 mm. To avoid the risk of electrocautery-induced damage, there is recent evidence about using cold snare polypectomy and cold EMR for such lesions. The aim of this pooled analysis is to report outcomes of cold snare resection for polyps ≥10 mm.

METHODS

PubMed/Medline, Embase, Google Scholar, and Cochrane databases were searched up to July 2018 to identify studies that performed cold snare resection for colorectal polyps ≥10 mm. Primary outcomes were adverse events (bleeding, perforation, and postpolypectomy abdominal pain), and secondary outcomes were the rates of complete resection, overall residual polyp rates, and rates for adenomas versus sessile serrated polyps (SSPs). Subgroup analysis was performed focusing on lesion size, location, and resection technique.

RESULTS

Eight studies were included in the final analysis that included 522 colorectal polyps with a mean polyp size of 17.5 mm (range, 10-60). The overall adverse event rate was 1.1% (95% confidence interval, CI, 0.2%-2.0%; I2 = 0%). Intra- and postprocedural bleeding rates were .7% (95% CI, 0%-1.4%) and .5% (95% CI, .1%-1.2%), respectively, with abdominal pain rate being .6% (95% CI, .1%-1.3%). Polyps ≥20 mm had a higher intraprocedural bleeding rate of 1.3% (95% CI, .7%-3.3%) and abdominal pain rate of 1.2% (95% CI, .7%-3.0%) but no delayed bleedings. No perforations were reported. The complete resection rate was 99.3% (95% CI, 98.6%-100%). Overall pooled residual rates of polyps of any histology, adenomas, and SSPs were 4.1% (95% CI, .2%-8.4%), 11.1% (95% CI, 4.1%-18.1%), and 1.0% (95% CI, .4%-2.4%), respectively, during a follow-up period ranging from 154 to 258 days.

CONCLUSIONS

The results of this systematic review and pooled analysis were excellent with cold snare resection of colorectal polyps >10 mm in terms of postpolypectomy bleeding, complete resection, and residual polyp rates. Randomized controlled trials comparing cold snare resection with hot snare resections of polyps ≥10 mm are required for further investigation.

Delayed Bleeding After Colorectal Endoscopic Submucosal Dissection: When Is Emergency Colonoscopy Needed?

BACKGROUND

Endoscopic submucosal dissection (ESD) is an effective treatment for early-colorectal cancer. Although delayed bleeding is a serious potential complication, there is no consensus on the optimal protocol to determine which cases require emergency colonoscopy.

AIMS

This study aimed to assess the risk factors for delayed bleeding after ESD and evaluate the "watch and wait" strategy for delayed bleeding. The "watch and wait" strategy was used for delayed bleeding, unless the shock index was ≥ 1 and/or a moderate amount of hematochezia occurred more than five occurrences.

METHODS

This study included 404 patients who had undergone endoscopic resection for 439 lesions between April 2012 and February 2018. Patients were classified into the bleeding group or the no-bleeding group to investigate the risk factors for delayed bleeding, and to assess the necessity of emergency colonoscopy.

RESULTS

Twenty-seven patients into the bleeding group and 412 into the no-bleeding group were classified. However, no case required emergency colonoscopy for hemostasis under "watch and wait strategy." Multivariate analysis revealed the risk factors for bleeding were rectal lesion (OR 5.547, 95% CI 1.456-21.130; P = 0.012) and lesion size ≥ 40 mm (OR 3.967, 95% CI 1.003-15.696; P = 0.05).

CONCLUSIONS

Risk factors for delayed bleeding are rectal lesions and lesion size ≥ 40 mm. This watch and wait strategy resulted in no requirements for emergency colonoscopy or blood transfusion, and no serious conditions caused by delayed bleeding.

A retrospective comparative study of argon plasma versus polypectome snare tip coagulation: effect on recurrence rate after resection of large laterally spreading type lesions

Background

Endoscopic mucosal resection (EMR) is an established technique for treating large laterally spreading type (LST) lesions ≥20 mm. The aim of our study was to compare the use of argon plasma (APC) versus snare-tip coagulation on the recurrence rate of large LST lesions.

Methods

All patients with large LST lesions resected by EMR between January 2006 and December 2014 were enrolled. After piecemeal resection, patients underwent either APC or snare-tip coagulation of the rim of the resection area and any residual adenomatous tissue. Follow up included colonoscopy and biopsies. Medical records, including characteristics of patients and polyps, complications and recurrence were retrieved and collected.

Results

One hundred one patients were included in the final analysis. They were divided into the APC group (n=50) and the snare-tip coagulation group (n=51). The 2 groups were similar concerning patients’ characteristics, size of polyps and histology. Post-polypectomy coagulation syndrome was observed in 8 patients (7.9%) (APC group: n=5 and snare tip group: n=3). EMR-related bleeding occurred in 9 patients (8.9%) (APC group: n=4 and snare tip group: n=5). Total recurrence rate was 14.85% (16% and 13.7% in APC and snare-tip groups, respectively, P=0.34).

Conclusion

The effectiveness of snare-tip coagulation is comparable with that of APC with respect to recurrence rate after resection of large LST lesions. It thus represents a cost-effective alternative to APC.

Wide-field endoscopic mucosal resection versus endoscopic submucosal dissection for laterally spreading colorectal lesions: a cost-effectiveness analysis

OBJECTIVE

To compare the cost-effectiveness of endoscopic submucosal dissection (ESD) and wide-field endoscopic mucosal resection (WF-EMR) for removing large sessile and laterally spreading colorectal lesions (LSLs) >20 mm.

DESIGN

An incremental cost-effectiveness analysis using a decision tree model was performed over an 18-month time horizon. The following strategies were compared: WF-EMR, universal ESD (U-ESD) and selective ESD (S-ESD) for lesions highly suspicious for containing submucosal invasive cancer (SMIC), with WF-EMR used for the remainder. Data from a large Western cohort and the literature were used to inform the model. Effectiveness was defined as the number of surgeries avoided per 1000 cases. Incremental costs per surgery avoided are presented. Sensitivity and scenario analyses were performed.

RESULTS

1723 lesions among 1765 patients were analysed. The prevalence of SMIC and low-risk-SMIC was 8.2% and 3.1%, respectively. Endoscopic lesion assessment for SMIC had a sensitivity and specificity of 34.9% and 98.4%, respectively. S-ESD was the least expensive strategy and was also more effective than WF-EMR by preventing 19 additional surgeries per 1000 cases. 43 ESD procedures would be required in an S-ESD strategy. U-ESD would prevent another 13 surgeries compared with S-ESD, at an incremental cost per surgery avoided of US$210 112. U-ESD was only cost-effective among higher risk rectal lesions.

CONCLUSION

S-ESD is the preferred treatment strategy. However, only 43 ESDs are required per 1000 LSLs. U-ESD cannot be justified beyond high-risk rectal lesions. WF-EMR remains an effective and safe treatment option for most LSLs.

TRIAL REGISTRATION NUMBER

NCT02000141.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Carbon dioxide insufflation during endoscopic resection of large colorectal polyps can reduce post-procedure abdominal pain: A prospective, double-blind, randomized controlled trial

Background

Studies of the use of CO₂ insufflation during endoscopic resection of large colorectal polyps (LCPs) are lacking.

Objective

We evaluated the effect of CO₂ insufflation on pain after endoscopic resection of LCPs.

Methods

In a prospective randomized controlled trial (RCT), 132 patients were randomly assigned to groups who underwent endoscopic resection with CO₂ insufflation (CO₂ group, n = 66) or air insufflation (air group, n = 66). The primary outcome was abdominal pain post-procedure (PP). The secondary outcomes were abdominal distension, rates of technical success, amounts of sedatives prescribed, use of analgesics, and adverse events.

Results

Baseline patient characteristics were similar between the groups. The mean abdominal pain score was 12.3 in the CO₂ group vs. 17.5 in the air group at 1 h PP (p  =  0.047). Also, the proportion of patients without pain was significantly higher in the CO₂ group at 1 h PP (p = 0.008). The pain score differed more in the endoscopic submucosal dissection group and long-time group. The secondary outcomes were not significantly different between the two groups.

Conclusions

The results of this RCT demonstrate the superiority of CO₂ insufflation for endoscopic resection of LCPs in terms of decreasing PP abdominal pain (KCT0001636).

Management of complex polyps of the colon and rectum

PUPRPOSE

Benign polyps that are technically challenging and unsafe to remove via polypectomy are known as complex polyps. Concerns regarding safety and completeness of resection dictate they undergo advanced endoscopic techniques, such as endoscopic mucosal resection or surgery. We provide a comprehensive overview of complex polyps and current treatment options.

METHODS

A review of the English literature was conducted to identifyarticles describing the management of complex polyps of the colon and rectum.

RESULTS

Endoscopic mucosal resection is the standard of care for the majority of complex polyps. Only polyps that fail endoscopic mucosal resection or are highly suspicious of invasive cancer but which cannot be removed endoscopically warrant surgery.

CONCLUSION

Several factors influence the treatment of a complex polyp; therefore, there cannot be a "one-size-fitsall" approach. Treatment should be tailored to the lesion's characteristics, the risk of adverse events, and the resources available to the treating physician.

Targeting Mucosal Endothelin-A-Receptor Expression by Fluorescence Endoscopy is Feasible to Detect and Characterize Colitis-Associated Cancer in Mice

BACKGROUND

To facilitate onsite decision-making during endoscopy, both accurate detection and in vivo characterization of preneoplasia are prerequisites. However, no endoscopy technique is available that meets both demands satisfactorily. We evaluated endothelin-receptor A (ETAR)-guided fluorescence endoscopy (FE) in vivo and fluorescence reflectance imaging (FRI) ex vivo for detection and characterization of early dysplastic colitis-associated colonic lesions.

METHODS

Colorectal cancerogenesis was investigated in the inflammatory driven AOM-DSS model and spontaneous adenoma development in ApcMin mice. A Cy5.5-labeled nonpeptidic ETAR-specific imaging probe was injected intravenously to assess tumor development in vivo by white light endoscopy (WLE) and FE. Ex vivo tumors were evaluated by FRI, histological examination, and western blot analysis. In addition, tissue samples from patients with colitis-associated malignant and nonmalignant mucosal alterations were analyzed. Specificity experiments were performed using an unspecific Cy3.5-glycine tracer.

RESULTS

Overall, 62 adenomas were observed. FE was able to detect and quantify ETAR expression targeting the ETAR-specific photoprobe. A significantly higher fluorescent contrast was detected in colonic adenomas compared to adjacent nonmalignant mucosa by FE (64.3 ± 7.9 vs. 56.6. ± 7.0; P < 0.001). These results were confirmed by FRI examination, immunochemistry, and western blot analysis. Additionally, ETAR expression in samples from human patients with colitis-associated cancer was highly elevated compared to nonmalignant alterations. Specificity experiments indicated a high binding-specificity of the applied ETAR photoprobe (1.4 ± 0.3 vs. 2.5 ± 0.7; P < 0.001).

CONCLUSIONS

We introduced ETAR guided FE in mice for successful in vivo detection and characterization of colorectal neoplasia on a molecular level.

The Difficult Colorectal Polyp

Difficult colorectal polyps represent lesions that pose a challenge to traditional endoscopic snare polypectomy. These polyps have historically been managed by surgical resection. Currently, several less invasive options are available to avoid colectomy. Repeat colonoscopy and snare polypectomy by an expert endoscopist, endoscopic mucosal resection, endoscopic submucosal dissection, and combined endoscopic and laparoscopic surgery have been developed to remove difficult polyps without the need for formal surgical resection. Patients with rectal polyps have the advantage of additional transanal minimally invasive techniques to enhance their resectability. Today, most colorectal polyps can be managed without the need for formal surgical resection.

Polyp Resection - Controversial Practices and Unanswered Questions

Detection and complete removal of precancerous neoplastic polyps are central to effective colorectal cancer screening. The prevalence of neoplastic polyps in the screening population in the United States is likely >50%. However, most persons with neoplastic polyps are never destined to develop cancer, and do not benefit for finding and removing polyps, and may only be harmed by the procedure. Further 70-80% of polyps are diminutive (≤5 mm) and such polyps almost never contain cancer. Given the questionable benefit, the high-cost and the potential risk changing our approach to the management of diminutive polyps is currently debated. Deemphasizing diminutive polyps and shifting our efforts to detection and complete removal of larger and higher-risk polyps deserves discussion and study. This article explores three controversies, and emerging concepts related to endoscopic polyp resection. First, we discuss challenges of optical resect-and-discard strategy and possible alternatives. Second, we review recent studies that support the use of cold snare resection for ≥5 mm polyps. Thirdly, we examine current evidence for prophylactic clipping after resection of large polyps.

Cold snare polypectomy for non-pedunculated colon polyps greater than 1 cm

Background and study aims Colonic polyps > 1 cm in size are commonly managed using hot polypectomy techniques. The most frequent adverse events (delayed bleeding, post-polypectomy syndrome, and perforation) are related to electrocautery-induced injury. We hypothesized that cold resection of large polyps may have similar efficacy and improved safety compared to hot polypectomy. Our aims were to evaluate efficacy and safety of piecemeal cold snare resection of colonic polyps > 1 cm. Patients and methods Patients undergoing lift and piecemeal cold snare polypectomy of non-pedunculated colon polyps > 1 cm from October 2013 to September 2015 were identified retrospectively. Efficacy was defined by the absence of residual adenomatous tissue at endoscopic follow-up. Adverse events (AEs), including post-procedural bleeding, bowel perforation, or post-procedural pain requiring hospitalization were assessed by chart review and telephone follow-up.  Results Seventy-three patients underwent piecemeal cold snare polypectomy for 94 colon polyps > 1 cm with 56 of 73 patients completing follow-up on 72 polyps. Residual or recurrent adenoma was found in 7 cases (9.7 %). Median polyp size was significantly greater in those with residual/recurrent adenoma (37.1 vs. 19.1 mm, P < .0001). There were no AEs among all 73 patients enrolled. Conclusions Piecemeal cold snare resection of colon polyps > 1 cm is feasible, safe and efficacious when compared to published hot polypectomy data. Additional observational and randomized comparative effectiveness studies are necessary to demonstrate comparable adenoma eradication and improved safety advantage over existing hot snare polypectomy techniques.

Handling and Pathology Reporting of Gastrointestinal Endoscopic Mucosal Resection

Endoscopic mucosal resection (EMR) is a non-invasive alternative to surgery that is now frequently used for resection of early lesions in both upper and lower parts of the gastrointestinal (GI) tract. One of the main advantages of these techniques is providing tissue for histopathological examination. Pathological examination of endoscopically resected specimens of GI tract is a crucial component of these procedures and is useful for prediction of both the risk of metastasis and lymph node involvement.

As the first step, it is very important for the pathologist to handle the EMR gross specimen in the correct way: it should be oriented, and then the margins should be labeled and inked accurately before fixation.

In the second step, the EMR pathological report should include all the detailed information about the diagnosis, grading, depth of invasion (mucosa only or submucosal involvement), status of the margins, and the presence or absence of lymphovascular invasion.

The current literature (PubMed and Google Scholar) was searched for the words "endoscopic mucosal resection" to find all relevant publications about this technique with emphasis on the pathologist responsibilities.

Safety of endoscopic mucosal resection (EMR) of large non-pedunculated colorectal adenomas in the elderly

BACKGROUND

Endoscopic mucosal resection (EMR) has been proven to be safe and effective for the treatment of colorectal adenomas. However, data are limited on the safety of this technique for large polyps and in elderly patients. Aims of our study were to examine the bleeding and perforation rates in patients with large non-pedunculated adenomas (≥20mm) and to evaluate the influence of size (≥40mm) and age (≥75 years) on the complication rates.

METHODS

In this multicenter retrospective study, patients who underwent EMR of non-pedunculated adenomas ≥20mm between January 2012 and March 2016 were included. The demographics of the patients, the use of antithrombotic drugs, size of the polyps, type of resection, pathology report, occurrence of post-polypectomy bleeding, and perforation- and recurrence rate were collected.

RESULTS

In 343 patients, 412 adenomas were removed. Eighty patients (23.3%) were ≥75 years of age, 138 polyps (33.5%) were ≥40mm. Bleeding complications were observed in 28 cases (6.8%) and were found significantly more frequent in adenomas ≥40mm, independent of the use of antithrombotic therapy. Five perforations (1.2%) were described, not related to the size of the polyp. There was no significant difference in complication rates between patients <75 years and patients ≥75 years. Bleeding complications rates were significantly higher in patients receiving double antithrombotic therapy.

CONCLUSION

EMR is safe in elderly patients. EMR of adenomas of ≥40mm was associated with more bleeding complications. Future studies should address how the bleeding rates can be reduced in these patients, especially in those who use double antithrombotic treatment.

Endoscopic Management of Large (≥2 cm) Non-pedunculated Colorectal Polyps: Impact of Polyp Morphology on Outcomes

BACKGROUND AND AIMS

Referrals for endoscopic management of large non-pedunculated (NP) colorectal polyps have increased as new techniques have emerged. The outcomes for referred large NP polyps based on the polyp morphology were investigated METHODS: A retrospective review of patients referred for large (≥20 mm) NP polyp management from January 2010 through June 2014 was completed. Polyp morphology was classified as either a NP polyp with depression (M1) or NP polyp with no depression (M0). Differences in treatment, histology, adverse events, outcomes at follow-up including residual disease, and need for surgical treatment were determined by morphology for all NP polyps ≥20 mm in size.

RESULTS

One-hundred and sixty-nine M1 and 136 M0 polyps ≥20 mm were removed endoscopically during the review period. Mean size was 31.9 ± 11.0 mm in M1, and 26.8 ± 9.5 mm in M0 group (p < 0.0001). En bloc resection was possible in 18.3 % of M1 and 30.9 % of M0 lesions (p = 0.011) with endoscopic submucosal dissection used in 13 and 2.2 % of polyps, respectively (p < 0.0001). Residual polyp was found in 26.5 % (27/102) of M1 and 13.6 % (12/88) of M0 patients at surveillance colonoscopy (p = 0.029). On multivariate analysis, piecemeal resection and M1 morphology showed significant association with residual polyp (OR 4.23, 95 % CI 1.23-14.59, p = 0.022, and OR 2.15, 95 % CI 1.004-4.62, p = 0.049, respectively).

CONCLUSION

Effective endoscopic management of large NP colorectal polyps, especially polyps without depression (M0), can be accomplished in the great majority of patients. Polyp morphology, particularly the presence or absence of depression, is a useful tool which influenced treatment, histology, and outcomes.

Colonic Polyps: Treatment

Colonic polyps are considered to be precursors of colon cancer based on several different molecular pathway models and should be resected with a principle of complete excisional biopsy. Several techniques are available for excisional biopsy, ranging from endoscopic techniques such as snare polypectomy, endoscopic mucosal resection (EMR), and endoscopic submucosal dissection (ESD) to surgical colonic resection and colonic endolaparoscopic surgery (CELS). This article focuses on these modalities with contemporary recommendations for choice of modality based on the size and features of the polyp encountered upon endoscopy. In addition, the morphologically apparent risk factors for polyps harboring invasive malignancy are discussed along with implications for management. Current literature on the comparative risks and benefits of EMR, ESD, CELS, and surgical resection is reviewed, as well as recommendations regarding cancer risk and subsequent surveillance.

Long-Term Outcome and Surveillance Colonoscopy after Successful Endoscopic Treatment of Large Sessile Colorectal Polyps

PURPOSE

Although there is a consensus about the need for surveillance colonoscopy after endoscopic resection, the interval remains controversial for large sessile colorectal polyps. The aim of this study was to evaluate the long-term outcome and the adequate surveillance colonoscopy interval required for sessile and flat colorectal polyps larger than 20 mm.

MATERIALS AND METHODS

A total of 204 patients with large sessile and flat polyps who received endoscopic treatment from May 2005 to November 2011 in a tertiary referral center were included.

RESULTS

The mean age was 65.1 years and 62.7% of the patients were male. The mean follow-up duration was 44.2 months and the median tumor size was 25 mm. One hundred and ten patients (53.9%) received a short interval surveillance colonoscopy (median interval of 6.3 months with range of 1-11 months) and 94 patients (46.1%) received a long interval surveillance colonoscopy (median interval of 13.6 months with range of 12-66 months). There were 14 patients (6.9%) who had local recurrence at the surveillance colonoscopy. Using multivariate regression analysis, a polyp size greater than 40 mm was shown to be independent risk factor for local recurrence. However, piecemeal resection and surveillance colonoscopy interval did not significantly influence local recurrence.

CONCLUSION

Endoscopic treatment of large sessile colorectal polyps shows a favorable long-term outcome. Further prospective study is mandatory to define an adequate interval of surveillance colonoscopy.

Endoscopic resection is cost-effective compared with laparoscopic resection in the management of complex colon polyps: an economic analysis

BACKGROUND AND AIMS

Endoscopic resection (ER) is an efficacious treatment for complex colon polyps (CCPs). Many patients are referred for surgical resection because of concerns over procedural safety, incomplete polyp resection, and adenoma recurrence after ER. Efficacy data for both resection strategies are widely available, but a paucity of data exist on the cost-effectiveness of each modality. The aim of this study was to perform an economic analysis comparing ER and laparoscopic resection (LR) strategies in patients with CCP.

METHODS

A decision analysis tree was constructed using decision analysis software. The 2 strategies (ER vs LR) were evaluated in a hypothetical cohort of patients with CCPs. A hybrid Markov model with a 10-year time horizon was used. Patients entered the model after colonoscopic diagnosis at age 50. Under Strategy I, patients underwent ER followed by surveillance colonoscopy at 3 to 6 months and 12 months. Patients with failed ER and residual adenoma at 12 months were referred for LR. Under Strategy II, patients underwent LR as primary treatment. Patients with invasive cancer were excluded. Estimates regarding ER performance characteristics were obtained from a systematic review of published literature. The Centers for Medicare & Medicaid Services (2012-2013) and the 2012 Healthcare Cost and Utilization Project databases were used to determine the costs and loss of utility. We assumed that all procedures were performed with anesthesia support, and patients with adverse events in both strategies required inpatient hospitalization. Baseline estimates and costs were varied by using a sensitivity analysis through the ranges.

RESULTS

LR was found to be more costly and yielded fewer quality-adjusted life-years (QALYs) compared with ER. The cost of ER of a CCP was $5570 per patient and yielded 9.640 QALYs. LR of a CCP cost $18,717 per patient and yielded fewer QALYs (9.577). For LR to be more cost-effective, the thresholds of 1-way sensitivity analyses were (1) technical success of ER for complete resection in <75.8% of cases, (2) adverse event rates for ER > 12%, and (3) LR cost of <$14,000.

CONCLUSIONS

Our data suggest that ER is a cost-effective strategy for removal of CCPs. The effectiveness is driven by high technical success and low adverse event rates associated with ER, in addition to the increased cost of LR.

Meta-analysis comparing differing methods of endoscopic therapy for colorectal lesions

AIM: To compare the outcomes of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) of colorectal lesions.

METHODS: An electronic systematic literature search of four computerized databases was performed in July 2014 identifying studies reporting the outcomes of colorectal ESD and EMR. The primary outcome measures were en-bloc resection rate, endoscopic clearance rate and lesion recurrence rate of the patients followed up. The secondary outcome was the complication rate (including bleeding, perforation and surgery post EMR or ESD rate). Statistical pooling and random effects modelling of the studies calculating risk difference, heterogeneity and assessment of bias and quality were performed.

RESULTS: Six observational studies reporting the outcomes of 1324 procedures were included. The en-bloc resection rate was 50% higher in the ESD group than in the EMR group (95%CI: 0.17-0.83, P < 0.0001, I² = 99.7%). Endoscopic clearance rates were also significantly higher in the ESD group (95%CI: -0.06-0.02, P < 0.0001, I² = 92.5%). The perforation rate was 7% higher in the ESD group than the EMR group (95%CI: 0.05-0.09, P > 0.05, I² = 41.1%) and the rate of recurrence was 50% higher in the EMR group than in the ESD group (95%CI: 0.20-0.79, P < 0.001, I² = 99.5%). Heterogeneity remained consistent when subgroup analysis of high quality studies was performed (with the exception of piecemeal resection rate), and overall effect sizes remained unchanged for all outcomes.

CONCLUSION: ESD demonstrates higher en-bloc resection rates and lower recurrence rates compared to colorectal EMR. Differences in outcomes may benefit from increased assessment through well-designed comparative studies.

Outcome and risk of recurrence for endoscopic resection of colonic superficial neoplastic lesions over 2 cm in diameter

BACKGROUND

Large colorectal superficial neoplastic lesions are challenging to remove. This study aimed to assess the outcomes of routine endoscopic resection of large (≥2 cm and <3 cm) and giant (≥3 cm) lesions.

METHODS

From 4587 endoscopic resections, 265 (5.7%) large and giant lesions were removed in 249 patients. We retrospectively analyzed 125 patients (141 endoscopic mucosal resection, 73 large and 68 giant lesions) with a follow-up of 6-12 months. Rate of en bloc and piecemeal resection, recurrence and risk factors were analyzed.

RESULTS

En bloc was performed in 92 cases (65.2%) and piecemeal resection in 49 (34.8%). A complete endoscopic resection was achieved in 139 cases (98.5%) with radical resection in 84/139 cases (60.4%). Argon plasma coagulation was applied in 18/141 lesions (12.8%). A recurrence occurred in 16/139 lesions (11.5%). The risk of recurrence at one year was significantly higher for giant than large lesions (p=0.03). The recurrence risk was higher in treated than in non-argon plasma coagulation treated lesions (p=0.01).

CONCLUSIONS

endoscopic mucosal resection is a safe and effective routine treatment for large superficial neoplastic lesions. The risk factors for recurrence include giant size, non-protruding morphology, piecemeal technique and argon plasma coagulation.

Cap-assisted Endoscopic Mucosal Resection is Highly Effective for Nonpedunculated Colorectal Lesions

GOALS

To assess the safety and efficacy of cap-assisted endoscopic mucosal resection (C-EMR) for nonpedunculated colorectal lesions.

BACKGROUND

There are little data supporting the safety and efficacy of C-EMR for colorectal polyps.

STUDY

A retrospective review was conducted on the medical records of 97 consecutive patients who underwent C-EMR for nonpedunculated colorectal lesions in a tertiary center by a single gastroenterologist (L.H.J.). Reported outcomes were: overall eradication rate that included all attempted C-EMRs, endoscopist-reported eradication rate that included C-EMRs reported as a success, and complications rate.

RESULTS

A total of 134 C-EMRs were performed on 124 nonpedunculated colorectal lesions within a 55-month period, with a median follow-up of 4.2 (1.6 to 46.8) months. Among the polyps with available follow-up, the overall eradication rate was 91% (81/89); the endoscopist-reported eradication rate was 98.8% (81/82). The complications rate was 10.2%: perforation (3.9%), intraprocedural bleeding (3.9%), and delayed bleeding (2.4%); all but 2 perforation cases that required surgical interventions (both occurring early in the time period in which procedures were performed), were treated endoscopically or conservatively with complete recovery.

CONCLUSIONS

C-EMR is highly effective in treating nonpedunculated colorectal lesions, which can be learned and practiced in the appropriate setting. Decline in the complications rate was observed as the endoscopist gained experience. Although perforation remains a relatively high risk, this may be decreased by increasing the fluid cushion, and decreasing suction pressure. Immediate recognition and endoscopic management of perforation can be highly successful. C-EMR is our suggested method in approaching nonpedunculated colon polyps, especially flat polyps that are not easily accessible by other endoscopic techniques.

Colorectal endoscopic submucosal dissection from a Western perspective: Today’s promises and future challenges

Over the last few years, endoscopic submucosal dissection (ESD) has shown to be effective in the management of early colorectal neoplasms, particularly in Asian countries where the technique was born. In the Western world, its implementation has been slow and laborious. In this paper, the indications for ESD, its learning model, the available methods to predict the presence of deep submucosal invasion before the procedure and the published outcomes from Asia and Europe will be reviewed. Since ESD has several limitations in terms of learning achievement in the West, and completion of the procedure for the first cases is difficult in our part of the world, a short review on colorectal assisted ESD has been included. Finally, other endoscopic and surgical treatment modalities that are in competition with colorectal ESD will be summarized.

Dynamic Article: Full-Thickness Excision for Benign Colon Polyps Using Combined Endoscopic Laparoscopic Surgery

BACKGROUND

Benign colon polyps are commonly encountered but may not always be amenable to endoscopic excision because of their size, shape, location, or scarring from previous attempts. The addition of laparoscopy allows a greater degree of bowel manipulation, but the current technique is still limited when encountering a polyp with inadequate lifting attributed to polyp morphology or scarring. We describe an extension to the existing combined endoscopic laparoscopic surgery technique using a full-thickness approach to increase polyp maneuverability and local excision of difficult but benign polyps.

OBJECTIVE

The purpose of this study was to report the technical details and preliminary results of a new approach for full-thickness excision of difficult colon polyps, combined endoscopic laparoscopic surgery full-thickness excision.

DESIGN

This study is a retrospective review of our experience from December 2013 to May 2015.

SETTINGS

The study was conducted at a single academic institution.

PATIENTS

All of the patients had previous incomplete colonoscopic polypectomy performed at other institutions. Patients were selected for our technique if the polyp had a benign appearance but was unable to be resected by traditional endoscopic or combined endoscopic laparoscopic surgery methods because of polyp morphology or scarring from previous biopsies.

MAIN OUTCOME MEASURES

The safety and feasibility of this procedure were measured.

RESULTS

Three patients underwent combined endoscopic laparoscopic surgery-full-thickness excision for difficult colon polyps. There were no intraoperative or postoperative complications. The length of stay was 1 day for all of the patients. All 3 of the patients had benign final pathology.

LIMITATIONS

This study was limited by the small number of patients in a single institution.

CONCLUSIONS

Full-thickness excision for benign colon polyps using combined endoscopic laparoscopic surgery is safe and feasible. Using this technique, difficult polyps not amenable to traditional endoscopic approaches can be removed and colectomy may be avoided.

Improving the utility of colonoscopy: Recent advances in practice

Colonoscopy is a frequently performed diagnostic and therapeutic test and the primary screening tool in several nationalized bowel cancer screening programs. There has been a considerable focus on maximizing the utility of colonoscopy. This has occurred in four key areas: Optimizing patient selection to reduce unnecessary or low yield colonoscopy has offered cost-benefit improvements in population screening. Improving quality assurance, through the development of widely accepted quality metrics for use in individual practice and the research setting, has offered measurable improvements in colonoscopic yield. Significant improvements have been demonstrated in colonoscopic technique, from the administration of preparation to the techniques employed during withdrawal of the colonoscope. Improved techniques to avoid post-procedural complications have also been developed-further maximizing the utility of colonoscopy. The aim of this review is to summarize the recent evidence-based advances in colonoscopic practice that contribute to the optimal practice of colonoscopy.

British Society of Gastroenterology/Association of Coloproctologists of Great Britain and Ireland guidelines for the management of large non-pedunculated colorectal polyps

These guidelines provide an evidence-based framework for the management of patients with large non-pedunculated colorectal polyps (LNPCPs), in addition to identifying key performance indicators (KPIs) that permit the audit of quality outcomes. These are areas not previously covered by British Society of Gastroenterology (BSG) Guidelines.A National Institute of Health and Care Excellence (NICE) compliant BSG guideline development process was used throughout and the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool was used to structure the guideline development process. A systematic review of literature was conducted for English language articles up to May 2014 concerning the assessment and management of LNPCPs. Quality of evaluated studies was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) Methodology Checklist System. Proposed recommendation statements were evaluated by each member of the Guideline Development Group (GDG) on a scale from 1 (strongly agree) to 5 (strongly disagree) with >80% agreement required for consensus to be reached. Where consensus was not reached a modified Delphi process was used to re-evaluate and modify proposed statements until consensus was reached or the statement discarded. A round table meeting was subsequently held to finalise recommendations and to evaluate the strength of evidence discussed. The GRADE tool was used to assess the strength of evidence and strength of recommendation for finalised statements.KPIs, a training framework and potential research questions for the management of LNPCPs were also developed. It is hoped that these guidelines will improve the assessment and management of LNPCPs.