Efficacy and safety of endoscopic resection of large colorectal polyps: a systematic review and meta-analysis

Colorectal endoscopic submucosal dissection (ESD)

Endoscopic submucosal dissection (ESD) is an interventional procedure for en-bloc resection of gastrointestinal lesions. ESD is a challenging and can involve a reasonable degree of risk, therefore case selection is of crucial importance, especially in the colo-rectum. This procedure should be mainly used for dissection of lesions when there is a high suspicion of superficial malignant invasion; several classifications have been proposed in order to better identify lesions suitable for ESD. However, case selection is still an issue, since only about 8-10% of dissected lesions are superficially invading cancer and most of cases involve benign or massively invading cancer. In addition, significant differences have been reported between Asian and Western countries in regard to main outcomes, and therefore measures should be adopted as soon as possible to reduce this discrepancy.

Colorectal endoscopic mucosal resection (EMR)

Colonoscopy has the benefit of detecting and treating precancerous adenomatous polyps and thus reduces mortality associated with CRC. Screening colonoscopy is the keystone for prevention of colorectal cancer. Over the last 20 years there has been increased in the management of large colorectal polyps from surgery to endoscopic removal techniques which is less invasive. Traditionally surgical resection was the treatment of choice for many years for larger polyps but colectomy poses significant morbidity of 14-46% and mortality of up to 7%. There are several advantages of endoscopic resection technique over surgery; it is less invasive, less expensive, has rapid recovery, and preserves the normal gut functions. In addition patient satisfaction and efficacy of EMR is higher with minor complications. Thus, this has facilitated the development of advanced resection technique for the treatment of large colorectal polyps called as endoscopic mucosal resection (EMR).

Recent Advances in Endoscopy

In this narrative review, invited by the Editors of Gastroenterology, we summarize recent advances in the field of gastrointestinal endoscopy. We have chosen articles published primarily in the past 2-3 years. Although a thorough literature review was performed for each topic, the nature of the article is subjective and systematic and is based on the authors' experience and expertise regarding articles we believed were most likely to be of high clinical and scientific importance.

Colorectal endoscopic submucosal dissection: patient selection and special considerations

Endoscopic submucosal dissection (ESD) enables en bloc resection of large complex colorectal superficial neoplastic lesions, resulting in very low rates of local recurrence, high-quality pathologic specimens for accurate histopathologic diagnosis and potentially curative treatment of early adenocarcinoma without resorting to major surgical resection. The safety and efficacy of the technique, which was pioneered in the upper gastrointestinal tract, has been established by the consistently impressive outcomes from expert centers in Japan and some other eastern countries. However, ESD is challenging to perform in the colorectum and there is a significant risk of complications, particularly in the early stages of the learning curve. Early studies from western centers raised concerns about the high complication rates, and the impressive results from Japanese centers were not replicated. As a result, many western endoscopists are skeptical about the role of ESD and few centers have incorporated the technique into their practice. Nevertheless, although the distribution of expertise, referral centers and modes of practice may differ in Japan and western countries, ESD has an important role and can be safely and effectively incorporated into western practice. Key to achieving this is meticulous lesion assessment and selection, appropriate referral to centers with the necessary expertise and experience and application of the appropriate technique individualized to the patient. This review discusses the advantages, risks and benefits of ESD to treat colorectal lesions and the importance of preprocedure lesion assessment and in vivo diagnosis and outlines a pragmatic rationale for appropriate lesion selection as well as the patient, technical and institutional factors that should be considered.

Effectiveness and safety of endoscopic resection for gastric GISTs: a systematic review

AIMS

To evaluate the effectiveness and safety of endoscopic resection for gastric gastrointestinal stromal tumors (GISTs).

MATERIAL AND METHODS

The effectiveness and safety of endoscopic resection were mainly assessed by complete resection rate, postoperative adverse event rate, and recurrence rate. Moreover, a comparison of endoscopic with laparoscopic resection for gastric GISTs was made through weighted mean difference by STATA 12.0 with regard to operation time, blood loss, and length of stay after including patients who underwent endoscopic or laparoscopic resection for gastric GISTs in the comparative studies.

RESULTS

Eleven studies investigating endoscopic resection for GISTs were included. For stromal tumors <2 cm in average diameters the pooled rates of complete resection, postoperative adverse events and recurrence were 0.97, 0.08, and 0.03, respectively. Only five retrospective studies directly compared endoscopic with laparoscopic resection for gastric GISTs with average diameters from 1.1 cm to 3.8 cm, and endoscopic resection had a shorter operation time than laparoscopic resection, but there were no significant differences in intraoperative blood loss, length of stay, postoperative complications, and postoperative recurrence rates between the two approaches.

CONCLUSIONS

Endoscopic resection is predominantly tried for gastric GISTs of relatively small size. It seems effective and safe for gastric GISTs <2 cm in average diameter, with relatively short operation times.

Clinical outcomes after endoscopic submucosal dissection for colorectal neoplasia: a systematic review and meta-analysis

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is an endoscopic resection technique for lesions suspicious of superficial malignancy. It is performed using an ESD knife on its own (standard technique) or by the sequential use of a knife and a snare (hybrid technique). The experience with these techniques is different in Asian and non-Asian countries. We performed a systematic review and meta-analysis of available evidence on colorectal ESD.

METHODS

Electronic databases were searched up to August 2016 for studies evaluating R0, en bloc resection, and adverse event rates of both techniques for the treatment of colorectal lesions. Proportions were pooled by a random effects model.

RESULTS

Ninety-seven studies (71 performed in Asia) evaluated the standard technique and 12 studies (7 in Asia) the hybrid technique. The R0 resection rate of the standard technique was 82.9%, and it was significantly lower in non-Asian versus Asian countries: 71.3% versus 85.6%. The en bloc resection rate was 91% and was significantly lower in non-Asian versus Asian countries (81.2% vs 93%, respectively). Surgery was needed in 1.1% of the ESD-related adverse events, with a significant difference between non-Asian and Asian countries (3.1% vs 0.8%). The R0 and en bloc resection rates with the hybrid technique were significantly lower than those achieved with the standard technique: 60.6% and 68.4%, respectively, with similar adverse event rates.

CONCLUSIONS

In non-Asian countries the standard ESD technique is still failing to achieve acceptable levels of performance. The hybrid technique showed low R0 resection rates and should not be considered as an adequate alternative to the standard technique.

Polypectomy and advanced endoscopic resection

Most colorectal cancers evolve from colorectal adenomatous polyps in a pathway known as the adenoma to carcinoma sequence. Early detection and removal of colorectal adenomas can prevent the development of colorectal cancer. The vast majority of these polyps can be resected endoscopically. Advances in endoscopic resection techniques have led to expanded indications for endoscopic polypectomy, whereby giant polyps, scarred lesions and early cancers may be cured. We will outline conventional endoscopic mucosal resection techniques as well as more complex resection methods such as endoscopic submucosal dissection, full thickness resection and the use of combined endoscopic and laparoscopic assisted approaches to resection. We will also explore the role of a virtual multidisciplinary team to aid decision-making when managing large and complex colorectal polyps. This review will provide an update on the endoscopic management of colorectal polyps and highlight exciting new developments in this ever-expanding field.

Adenoma recurrence after piecemeal colonic EMR is predictable: the Sydney EMR recurrence tool

BACKGROUND AND AIMS

EMR is the primary treatment of large laterally spreading lesions (LSLs) in the colon. Residual or recurrent adenoma (RRA) is a major limitation. We aimed to identify a robust method to stratify the risk of RRA.

METHODS

Prospective multicenter data on consecutive LSLs ≥20 mm removed by piecemeal EMR from 8 Australian tertiary-care centers were included (September 2008 until May 2016). A logistic regression model for endoscopically determined recurrence (EDR) was created on a randomly selected half of the cohort to yield the Sydney EMR recurrence tool (SERT), a 4-point score to stratify the incidence of RRA based on characteristics of the index EMR. SERT was validated on the remainder of the cohort.

RESULTS

Analysis was performed on 1178 lesions that underwent first surveillance colonoscopy (SC1) (median 4.9 months, interquartile range [IQR] 4.9-6.2). EDR was detected in 228 of 1178 (19.4%) patients. LSL size ≥40 mm (odds ratio [OR] 2.47; P < .001), bleeding during the procedure (OR 1.78; P = .024), and high-grade dysplasia (OR 1.72; P = .029) were identified as independent predictors of EDR and allocated scores of 2, 1, and 1, respectively to create SERT. Lesions with SERT scores of 0 (SERT = 0) had a negative predictive value of 91.3% for RRA at SC1, and SERT was shown to stratify RRA to specific follow-up intervals by using Kaplan Meier curves (log-rank P < .001).

CONCLUSIONS

Guidelines recommend SC1 within 6 months of EMR. SERT accurately stratifies the incidence of RRA after EMR. SERT = 0 lesions could safely undergo first surveillance at 18 months, whereas lesions with SERT scores between 1 and 4 (SERT 1-4) require surveillance at 6 and 18 months. (Clinical trial registration number: NCT01368289.).

Management of early colonic neoplasia: where are we now and where are we heading?

There have been considerable advances in the endoscopic treatment of colorectal neoplasia. The development of endoscopic submucosal dissection and full thickness resection techniques is changing the way benign disease and early cancers are managed. This article reviews the evidence behind these new techniques and discusses where this field is likely to move in the future. Areas covered: A PubMed literature review of resection techniques for colonic neoplasia was performed. The clinical and cost effectiveness of endoscopic mucosal resection (EMR) is examined. The development of endoscopic submucosal dissection (ESD) and knife assisted resection is described and issues around training reviewed. Efficacy is compared to both EMR and transanal endoscopic microsurgery. The future is considered, including full thickness resection techniques and robotic endoscopy. Expert commentary: The perceived barriers to ESD are falling, and views that such techniques are only possible in Japan are disappearing. The key barriers to uptake will be training, and the development of educational programmes should be seen as a priority. The debate between TEMS and ESD will continue, but ESD is more flexible and cheaper. This will become less significant as the number of endoscopists trained in ESD grows and some TEMS surgeons may shift across towards ESD.

Optimizing Resection of Large Colorectal Polyps

OPINION STATEMENT

Polypectomy reduces the incidence and mortality of colorectal cancer (CRC). The widespread adoption of CRC screening, more rigorous colonoscopy techniques, and advancements in endoscopic imaging have led to a greater awareness of complex polyps. Whereas surgery was once considered necessary for many large sessile or laterally spreading lesions (LSLs) in the colorectum, the majority can now be removed endoscopically. Endoscopic mucosal resection (EMR) is an established technique for treatment of colorectal LSLs. When performed by experts, EMR is highly effective and safe and can be completed in an outpatient or day-stay setting. Advancements in EMR effectiveness encompass a better understanding of the factors leading to post-EMR recurrence, protocols to recognize and treat it, and interventions that prevent recurrent or residual adenoma. New techniques for treating intra-procedural bleeding and a novel classification system to identify and inform proactive management of deep mural injury enhance the safety profile of EMR. However, each of these incremental advancements necessitates a meticulous and systematic approach that only committed and properly trained endoscopists can master. While alternative interventions such as endoscopic submucosal dissection (ESD) offer potential advantages over EMR, the added procedural complexity, risks, and costs limit the relevance of ESD to a minority of lesions in the colorectum. This article reviews the expanding body of evidence supporting EMR as the first-line treatment of colorectal LSLs ≥20 mm.

Extended endoscopic mucosal resection does not reduce recurrence compared with standard endoscopic mucosal resection of large laterally spreading colorectal lesions

BACKGROUND AND AIMS

Effective interventions to prevent residual and/or recurrent adenoma (RRA) after EMR of large sessile and laterally spreading colorectal lesions (LSL) are yet to be determined. RRA may occur due to inconspicuous adenoma at the EMR margin. We aimed to determine the efficacy and safety of extended EMR (X-EMR) compared with standard EMR (S-EMR).

METHODS

A single-center post hoc analysis of LSL ≥20 mm referred for treatment was performed. S-EMR was the standard sequential inject and resect method including a 1-mm to 2-mm margin of normal mucosa around the lesion. With X-EMR, at least a 5-mm margin of normal mucosa was excised. Patient and lesion characteristics and procedural outcomes were recorded. The primary endpoint was RRA at first surveillance colonoscopy at 4 months.

RESULTS

Between January 2009 and May 2011, 471 lesions (mean size, 37.9 mm) in 424 patients were resected by S-EMR, and between January 2012 and December 2013, 448 lesions (mean size, 39.1 mm) in 396 patients were resected by X-EMR. Resection was successful in 92.3% and 92.6% of referred lesions in the S-EMR and X-EMR groups, respectively (P = .978). X-EMR was independently associated with a higher risk of intraprocedural bleeding (IPB) (odds ratio, 3.1; 95% confidence interval [CI], 2.0-5.0; P < .001) but not other adverse events. RRA was present in 39 of 333 patients (11.7%) and 30 of 296 patients (10.1%) in the S-EMR and X-EMR groups, respectively (P = .15). X-EMR was not related to recurrence (hazard ratio, 0.8; 95% CI, 0.5-1.3; P = .399).

CONCLUSIONS

X-EMR does not reduce RRA and increases the risk of IPB compared with S-EMR. Alternative methods for the prevention of RRA are required.

The potential impact of local excision for T1 colonic cancer in elderly and comorbid populations: a decision analysis

BACKGROUND

Population-based bowel cancer screening has resulted in increasing numbers of patients with T1 colonic cancer. The need for colectomy in this group is questioned due to the low risk of lymphatic spread and increased treatment morbidity, particularly for elderly, comorbid patients. This study examined the quality-of-life benefits and risks of endoscopic resection compared with results after colectomy, for low-risk and high-risk T1 colonic cancer.

METHODS

Decision analysis using a Markov simulation model was performed; patients were managed with either endoscopic resection (advanced therapeutic endoscopy) or colectomy. Lesions were considered high risk according to accepted national guidelines. Probabilities and utilities (perception of quality of life) were derived from published data. Hypothetical cohorts of 65- and 80-year-old, fit and unfit patients with low-risk or high-risk T1 colonic cancer were studied. The primary outcome was quality-adjusted life expectancy (QALE) in life-years (QALYs).

RESULTS

In low-risk T1 colonic neoplasia, endoscopic resection increases QALE by 0.09 QALYS for fit 65-year-olds and by 0.67 for unfit 80-year-olds. For high-risk T1 cancers, the QALE benefit for surgical resection is 0.24 QALYs for fit 65-year-olds and the endoscopic QALE benefit is 0.47 for unfit 80-year-olds. The model findings only favored surgery with high local recurrence rates and when quality of life under surveillance was perceived poorly.

CONCLUSIONS

Under broad assumptions, endoscopic resection is a reasonable treatment option for both low-risk and high-risk T1 colonic cancer, particularly in elderly, comorbid patients. Exploration of methods to facilitate endoscopic resection of T1 colonic neoplasia appears warranted.

Expert opinions and scientific evidence for colonoscopy key performance indicators

Colonoscopy is a widely performed procedure with procedural volumes increasing annually throughout the world. Many procedures are now performed as part of colorectal cancer screening programmes. Colonoscopy should be of high quality and measures of this quality should be evidence based. New UK key performance indicators and quality assurance standards have been developed by a working group with consensus agreement on each standard reached. This paper reviews the scientific basis for each of the quality measures published in the UK standards.

Endoscopic resection of colorectal polyps in patients on antiplatelet therapy: an evidence-based guidance for clinicians

Due to the rising prevalence of coronary heart disease, endoscopists are more frequently performing a polypectomy in patients on antiplatelet therapy (APT) and dual antiplatelet therapy (DATP). Despite the availability of several guidelines with regard to the management of antiplatelet drugs during the periprocedure period, there is still variability in the current clinical practice. This may be influenced by the low quality of the evidence supporting recommendations, because most of the studies dealing with APT and polypectomy are observational and retrospective, and include mainly small (< 10 mm) polyps. However, some recommendations can still be made. An estimation of the bleeding and thrombotic risk of the patient should be made in advance. In the case of DAPT the procedure should be postponed, at least until clopidogrel can be safely withheld. If possible, non-aspirin antiplatelet drugs should be withheld 5-7 days before the procedure. Polyp size is the main factor related with post-polypectomy bleeding and it is the factor that should drive clinical decisions regarding the resection method and the use of endoscopic prophylactic measures. Non-aspirin antiplatelet agents can be reintroduced 24-48 hours after the procedure. In conclusion, there is little data with regard to the management of DAPT in patients with a scheduled polypectomy. Large randomized controlled trials are needed to support clinical recommendations.

Evaluation and long-term outcomes of the different modalities used in colonic endoscopic mucosal resection

Endoscopic mucosal resection (EMR) has been used in western countries to remove colonic polyps for at least the last two decades. Significant experience has been accumulated and the efficacy of the method has recently been evaluated in a large meta-analysis. A number of variations to modify the technique, including knife-assisted, cap-assisted, ligation devices, and underwater EMR, have been developed in an attempt to improve outcomes. However, to date there are only limited data comparing these techniques or demonstrating the superiority of any one of them. This article reviews the current evidence on the efficacy of each of these modified techniques.

Colorectal endoscopic submucosal dissection: a systematic review and meta-analysis

Background and study aims: Endoscopic submucosal dissection (ESD) is an advanced endoscopic technique that allows en-bloc resection of gastrointestinal tumor. We systematically review the medical literature in order to evaluate the safety and efficacy of colorectal ESD. Patients and methods: We performed a comprehensive literature search of MEDLINE, EMBASE, Ovid, CINAHL, and Cochrane for studies reporting on the clinical efficacy and safety profile of colorectal ESD. Results: Included in this study were 13833 tumors in 13603 patients (42 % female) who underwent colorectal ESD between 1998 and 2014. The R0 resection rate was 83 % (95 % CI, 80 - 86 %) with significant between-study heterogeneity (P < 0.001) which was partly explained by difference in continent (P = 0.004), study design (P = 0.04), duration of the procedure (P = 0.009), and, marginally, by average tumor size (P = 0.09). Endoscopic en bloc and curative resection rates were 92 % (95 % CI, 90 - 94 %) and 86 % (95 % CI, 80 - 90 %), respectively. The rates of immediate and delayed perforation were 4.2 % (95 % CI, 3.5 - 5.0 %) and 0.22 % (95 % CI, 0.11 - 0.46 %), respectively, while rates of immediate and delayed major bleeding were 0.75 % (95 % CI, 0.31 - 1.8 %) and 2.1 % (95 % CI, 1.6 - 2.6 %). After an average postoperative follow up of 19 months, the rate of tumor recurrence was 0.04 % (95 % CI, 0.01 - 0.31) among those with R0 resection and 3.6 % (95 % CI, 1.4 - 8.8 %) among those without R0 resection. Overall, irrespective of the resection status, recurrence rate was 1.0 % (95 % CI, 0.42 - 2.1 %). Conclusions: Our meta-analysis, the largest and most comprehensive assessment of colorectal ESD to date, showed that colorectal ESD is safe and effective for colorectal tumors and warrants consideration as first-line therapy when an expert operator is available.

Update on Difficult Polypectomy Techniques

Endoscopists often encounter colon polyps that are technically difficult to resect. These lesions traditionally were managed surgically, with significant potential morbidity and mortality. Recent advances in endoscopic techniques and instruments have allowed endoscopists to safely and effectively remove colorectal lesions with high technical and clinical success and potentially avoid invasive surgery. Endoscopic mucosal resection (EMR) has gained acceptance as the first-line therapy for large colorectal lesions. Endoscopic submucosal dissection (ESD) has been reported to be associated with higher rate of en bloc resection and less risk of short-time recurrence, but with an increased risk of adverse events. Therefore, the role of colorectal ESD should be restricted to lesions with high-risk morphologic features of submucosal invasion. In this article, we review the recent literature on the endoscopic management of difficult colorectal neoplasms.

A Scoring System to Determine Risk of Delayed Bleeding After Endoscopic Mucosal Resection of Large Colorectal Lesions

BACKGROUND & AIMS

After endoscopic mucosal resection (EMR) of colorectal lesions, delayed bleeding is the most common serious complication, but there are no guidelines for its prevention. We aimed to identify risk factors associated with delayed bleeding that required medical attention after discharge until day 15 and develop a scoring system to identify patients at risk.

METHODS

We performed a prospective study of 1214 consecutive patients with nonpedunculated colorectal lesions 20 mm or larger treated by EMR (n = 1255) at 23 hospitals in Spain, from February 2013 through February 2015. Patients were examined 15 days after the procedure, and medical data were collected. We used the data to create a delayed bleeding scoring system, and assigned a weight to each risk factor based on the β parameter from multivariate logistic regression analysis. Patients were classified as being at low, average, or high risk for delayed bleeding.

RESULTS

Delayed bleeding occurred in 46 cases (3.7%, 95% confidence interval, 2.7%-4.9%). In multivariate analysis, factors associated with delayed bleeding included age ≥75 years (odds ratio [OR], 2.36; P < .01), American Society of Anesthesiologist classification scores of III or IV (OR, 1.90; P ≤ .05), aspirin use during EMR (OR, 3.16; P < .05), right-sided lesions (OR, 4.86; P < .01), lesion size ≥40 mm (OR, 1.91; P ≤ .05), and a mucosal gap not closed by hemoclips (OR, 3.63; P ≤ .01). We developed a risk scoring system based on these 6 variables that assigned patients to the low-risk (score, 0-3), average-risk (score, 4-7), or high-risk (score, 8-10) categories with a receiver operating characteristic curve of 0.77 (95% confidence interval, 0.70-0.83). In these groups, the probabilities of delayed bleeding were 0.6%, 5.5%, and 40%, respectively.

CONCLUSIONS

The risk of delayed bleeding after EMR of large colorectal lesions is 3.7%. We developed a risk scoring system based on 6 factors that determined the risk for delayed bleeding (receiver operating characteristic curve, 0.77). The factors most strongly associated with delayed bleeding were right-sided lesions, aspirin use, and mucosal defects not closed by hemoclips. Patients considered to be high risk (score, 8-10) had a 40% probability of delayed bleeding.

Efficacy and safety of endoscopic mucosal resection of non-ampullary duodenal polyps: a systematic review

BACKGROUND AND AIMS

Data on the safety and efficacy of endoscopic resection of non-ampullary duodenal polyps are limited. This study evaluated the safety and efficacy of endoscopic mucosal resection (EMR) of sporadic non-ampullary duodenal polyps.

METHODS

Relevant studies for the meta-analysis were identified through search of PUBMED and EMBASE databases. Studies employing EMR for the management of sporadic duodenal polyps in the non-ampullary region were included. The primary outcome was the surgical intervention rates due to non-curative endoscopic resection (incomplete removal/recurrence necessitating surgery) and/or management of procedural adverse events.

RESULTS

A total of 440 patients (485 duodenal polyps) from 14 studies were included. The mean size of the polyps was 13 mm to 35 mm. Surgical intervention due to non-curative EMR and adverse events was required in 2 % (95 % confidence interval [CI] 0 - 4 %). EMR was successfully accomplished in 93 % (95 %CI 89 - 97 %). The overall bleeding rate after EMR was 16 % (95 %CI 10 - 23 %), and the pooled delayed bleeding rate was 5 % (95 %CI 2 - 7 %). The overall incidence of perforation was 1 % (95 %CI 1 - 3 %). Over a median follow-up period of 6 - 72 months, the recurrence rate after EMR was 15 % (95 %CI 7 - 23 %). Six studies (pooled recurrence 20 %, 95 %CI 14 - 27 %) reported on the outcomes of managing recurrent polyps, for which endoscopic removal was successful in 62 % (95 %CI 37 - 87 %). There was no procedure related mortality.

CONCLUSION

EMR appears to be a safe and effective therapeutic option for management of sporadic non-ampullary duodenal polyps. Long-term endoscopic surveillance is required to manage and treat recurrent disease.

Endoscopic mucosal resection (EMR) versus endoscopic submucosal dissection (ESD) for resection of large distal non-pedunculated colorectal adenomas (MATILDA-trial): rationale and design of a multicenter randomized clinical trial

Background

Endoscopic mucosal resection (EMR) is currently the most used technique for resection of large distal colorectal polyps. However, in large lesions EMR can often only be performed in a piecemeal fashion resulting in relatively low radical (R0)-resection rates and high recurrence rates. Endoscopic submucosal dissection (ESD) is a newer procedure that is more difficult resulting in a longer procedural time, but is promising due to the high en-bloc resection rates and the very low recurrence rates. We aim to evaluate the (cost-)effectiveness of ESD against EMR on both short (i.e. 6 months) and long-term (i.e. 36 months). We hypothesize that in the short-run ESD is more time consuming resulting in higher healthcare costs, but is (cost-) effective on the long-term due to lower patients burden, a higher number of R0-resections and lower recurrence rates with less need for repeated procedures.

Methods

This is a multicenter randomized clinical trial in patients with a non-pedunculated polyp larger than 20 mm in the rectum, sigmoid, or descending colon suspected to be an adenoma by means of endoscopic assessment. Primary endpoint is recurrence rate at follow-up colonoscopy at 6 months. Secondary endpoints are R0-resection rate, perceived burden and quality of life, healthcare resources utilization and costs, surgical referral rate, complication rate and recurrence rate at 36 months. Quality-adjusted-life-year (QALY) will be estimated taking an area under the curve approach and using EQ-5D-indexes. Healthcare costs will be calculated by multiplying used healthcare services with unit prices. The cost-effectiveness of ESD against EMR will be expressed as incremental cost-effectiveness ratios (ICER) showing additional costs per recurrence free patient and as ICER showing additional costs per QALY.

Discussion

If this trial confirms ESD to be favorable on the long-term, the burden of extra colonoscopies and repeated procedures can be prevented for future patients.

Trial registration

NCT02657044 (Clinicaltrials.gov), registered January 8, 2016.

Endoscopic resection of colorectal lesions: The narrowing divide between East and West

Colonic polypectomy is an effective way of reducing colon cancer mortality. Multiple techniques now exist for the resection of polyps, and the endoscopist must decide on the appropriate resection approach for individual patients and lesions. This decision should maximize efficacy, safety and cost-effectiveness and provide optimal oncological outcomes while minimizing unnecessary surgical treatment. Advances in endoscopic imaging technology are improving the accuracy of endoscopic diagnosis and allowing more precise risk assessment of colonic lesions. Resection technique can be tailored to the endoscopic findings. Diminutive (≤5 mm) and small polyps (≤9 mm) are best resected primarily by snare techniques. Cold snare polypectomy has proven safety, but efficacy and technique require further study. There is variation in techniques used for polyps 6-20 mm in size and incomplete resection rates for conventional polypectomy may be considerable. Endoscopic mucosal resection (EMR) is well established, safe and effective for lesions without submucosal invasion (SMI); however, recurrence is a key limitation. Endoscopic submucosal dissection (ESD) is well established in the East; however, it is resource intensive and its role in lesions with a low risk of SMI is questionable. ESD in the West remains incompletely defined and is associated with high adverse event rates, but it is becoming increasingly available and successful as experience grows. Emerging full-thickness resection technologies are still in their infancy and remain experimental as a result of the absence of reliable closure devices and techniques. Patient-focused outcomes should guide technique selection.

Coagulation syndrome: Delayed perforation after colorectal endoscopic treatments

Various procedure-related adverse events related to colonoscopic treatment have been reported. Previous studies on the complications of colonoscopic treatment have focused primarily on perforation or bleeding. Coagulation syndrome (CS), which is synonymous with transmural burn syndrome following endoscopic treatment, is another typical adverse event. CS is the result of electrocoagulation injury to the bowel wall that induces a transmural burn and localized peritonitis resulting in serosal inflammation. CS occurs after polypectomy, endoscopic mucosal resection (EMR), and even endoscopic submucosal dissection (ESD). The occurrence of CS after polypectomy or EMR varies according previous reports; most report an occurrence rate around 1%. However, artificial ulcers after ESD are largely theoretical, and CS following ESD was reported in about 9% of cases, which is higher than that for CS after polypectomy or EMR. Most cases of post-polypectomy syndrome (PPS) have an excellent prognosis, and they are managed conservatively with medical therapy. PPS rarely develops into delayed perforation. Delayed perforation is a severe adverse event that often requires emergency surgery. Since few studies have reported on CS and delayed perforation associated with CS, we focused on CS after colonoscopic treatments in this review. Clinicians should consider delayed perforation in CS patients.