Colon polypectomy: a review of routine and advanced techniques

Cold Versus Hot Snare Endoscopic Resection of Large Nonpedunculated Colorectal Polyps: Randomized Controlled German CHRONICLE Trial

BACKGROUND & AIMS

Endoscopic mucosal resection (EMR) is standard therapy for nonpedunculated colorectal polyps ≥20 mm. It has been suggested recently that polyp resection without current (cold resection) may be superior to the standard technique using cutting/coagulation current (hot resection) by reducing adverse events (AEs), but evidence from a randomized trial is missing.

METHODS

In this randomized controlled multicentric trial involving 19 centers, nonpedunculated colorectal polyps ≥20 mm were randomly assigned to cold or hot EMR. The primary outcome was major AE (eg, perforation or postendoscopic bleeding). Among secondary outcomes, major AE subcategories, postpolypectomy syndrome, and residual adenoma were most relevant.

RESULTS

Between 2021 and 2023, there were 396 polyps in 363 patients (48.2% were female) enrolled for the intention-to-treat analysis. Major AEs occurred in 1.0% of the cold group and in 7.9% of the hot group (P = .001; odds ratio [OR], 0.12; 95% CI, 0.03-0.54). Rates for perforation and postendoscopic bleeding were significantly lower in the cold group, with 0% vs 3.9% (P = .007) and 1.0% vs 4.4% (P = .040). Postpolypectomy syndrome occurred with similar frequency (3.1% vs 4.4%; P = .490). After cold resection, residual adenoma was found more frequently, with 23.7% vs 13.8% (P = .020; OR, 1.94; 95% CI, 1.12-3.38). In multivariable analysis, lesion diameter of ≥4 cm was an independent predictor both for major AEs (OR, 3.37) and residual adenoma (OR, 2.47) and high-grade dysplasia/cancer for residual adenoma (OR, 2.92).

CONCLUSIONS

Cold resection of large, nonpedunculated colorectal polyps appears to be considerably safer than hot EMR; however, at the cost of a higher residual adenoma rate. Further studies have to confirm to what extent polyp size and histology can determine an individualized approach. German Clinical Trials Registry (Deutsches Register Klinischer Studien), Number DRKS00025170.

Post-endoscopic submucosal dissection electrocoagulation syndrome: a clinical overview

INTRODUCTION

Post-endoscopic submucosal dissection electrocoagulation syndrome (PEECS) is a rare complication following endoscopic submucosal dissection (ESD). However, many aspects of PEECS are still controversial and there is a lack of up-to-date review. The aim of this article is to provide a comprehensive review on PEECS.

AREAS COVERED

The English-language literature was searched for articles on PEECS, with a focus on its pathogenesis, definition, and diagnosis, incidence rate, risk factors, prevention, management, and prognosis.

EXPERT OPINION

Many aspects of PEECS are still controversial such as etiology, diagnostic criteria, prevention and management. The recent studies tend to agree on the diagnostic criteria for PEECS, defined as localized abdominal tenderness and fever or inflammatory response without delayed perforation. Most patients with PEECS have a favorable prognosis with conservative treatment and more high-quality studies are needed in the controversial aspects mentioned above.

Colo-colonic intussusception with post-polypectomy electrocoagulation syndrome: A case report

BACKGROUND

Post-polypectomy electrocoagulation syndrome (PPES) can occur after colonoscopic polypectomy and is usually treated conservatively with a positive prognosis. Nevertheless, there can be cases with complications developing.

CASE SUMMARY

A 58-year-old woman, who had no previous medical history, visited the Emergency Department of another hospital with symptoms of abdominal pain and fever, 1 d after multiple colonoscopic polypectomies. An abdominopelvic computed tomography (CT) scan demonstrated colo-colonic intussusception, and she was transferred to our hospital to consider an operation. CT showed colo-colonic intussusception with PPES and no evidence of obstruction. The physical examination showed localized mild tenderness on the right sided abdomen. The patient fasted and was admitted for treatment with intravenous antibiotics (piperacillin/tazobactam 4.5 g each 8 h, ornidazole 500 mg each 12 h). After admission, the symptoms got better and a follow-up CT scan demonstrated resolution of the PPES and intussusception. The patient was discharged on hospital day 9.

CONCLUSION

Colo-colic intussusception can occur with PPES, and it can be properly treated conservatively.

Novel Pixelwise Co-Registered Hematoxylin-Eosin and Multiphoton Microscopy Image Dataset for Human Colon Lesion Diagnosis

Colorectal cancer presents one of the most elevated incidences of cancer worldwide. Colonoscopy relies on histopathology analysis of hematoxylin-eosin (H&E) images of the removed tissue. Novel techniques such as multi-photon microscopy (MPM) show promising results for performing real-time optical biopsies. However, clinicians are not used to this imaging modality and correlation between MPM and H&E information is not clear. The objective of this paper is to describe and make publicly available an extensive dataset of fully co-registered H&E and MPM images that allows the research community to analyze the relationship between MPM and H&E histopathological images and the effect of the semantic gap that prevents clinicians from correctly diagnosing MPM images. The dataset provides a fully scanned tissue images at 10x optical resolution (0.5 µm/px) from 50 samples of lesions obtained by colonoscopies and colectomies. Diagnostics capabilities of TPF and H&E images were compared. Additionally, TPF tiles were virtually stained into H&E images by means of a deep-learning model. A panel of 5 expert pathologists evaluated the different modalities into three classes (healthy, adenoma/hyperplastic, and adenocarcinoma). Results showed that the performance of the pathologists over MPM images was 65% of the H&E performance while the virtual staining method achieved 90%. MPM imaging can provide appropriate information for diagnosing colorectal cancer without the need for H&E staining. However, the existing semantic gap among modalities needs to be corrected.

Analysis on the Characterization of Multiphoton Microscopy Images for Malignant Neoplastic Colon Lesion Detection under Deep Learning Methods

Background:

Colorectal cancer has a high incidence rate worldwide, with over 1.8 million new cases and 880,792 deaths in 2018. Fortunately, its early detection significantly increases the survival rate, reaching a cure rate of 90% when diagnosed at a localized stage. Colonoscopy is the gold standard technique for detection and removal of colorectal lesions with potential to evolve into cancer. When polyps are found in a patient, the current procedure is their complete removal. However, in this process, gastroenterologists cannot assure complete resection and clean margins which are given by the histopathology analysis of the removed tissue, which is performed at laboratory.

Aims:

In this paper, we demonstrate the capabilities of multiphoton microscopy (MPM) technology to provide imaging biomarkers that can be extracted by deep learning techniques to identify malignant neoplastic colon lesions and distinguish them from healthy, hyperplastic, or benign neoplastic tissue, without the need for histopathological staining.

Materials and Methods:

To this end, we present a novel MPM public dataset containing 14,712 images obtained from 42 patients and grouped into 2 classes. A convolutional neural network is trained on this dataset and a spatially coherent predictions scheme is applied for performance improvement.

Results:

We obtained a sensitivity of 0.8228 ± 0.1575 and a specificity of 0.9114 ± 0.0814 on detecting malignant neoplastic lesions. We also validated this approach to estimate the self-confidence of the network on its own predictions, obtaining a mean sensitivity of 0.8697 and a mean specificity of 0.9524 with the 18.67% of the images classified as uncertain.

Conclusions:

This work lays the foundations for performing in vivo optical colon biopsies by combining this novel imaging technology together with deep learning algorithms, hence avoiding unnecessary polyp resection and allowing in situ diagnosis assessment.

Gastrointestinal and Nongastrointestinal Complications of Esophagogastroduodenoscopy and Colonoscopy in the Real World: A Nationwide Standard Cohort Using the Common Data Model Database

Background/Aims

The global trend of an expanding aged population has increased concerns about complications correlated with gastrointestinal (GI) endoscopy in elderly patients; however, there have been few reports published on this issue.

Methods

In this retrospective, observational cohort study performed between 2012 and 2017, serious complications of esophagogastroduodenoscopy (EGD), colonoscopy, and colonoscopic polypectomy were compared between patients according to age (≥65 years vs 18–64 years). We used the Health Insurance Review and Assessment-National Patient Samples database, previously converted to the standardized Observational Medical Outcomes Partnership-Common Data Model. Serious complications within 30 days of the procedure included both GI complications (bleeding and perforation) and non-GI complications (cerebrovascular accident [CVA], acute myocardial infarction [AMI], congestive heart failure [CHF], and death).

Results

A total of 387,647 patients who underwent EGD, 241,094 who underwent colonoscopy, and 89,059 who underwent colonoscopic polypectomy were assessed as part of this investigation. During the study period, endoscopic procedures in the older group steadily increased in number in all endoscopy groups (all p<0.001). Further, pooled complication rates of bleeding, CVA, AMI, CHF, and death were approximately three times higher among older patients who underwent EGD or colonoscopy. Moreover, pooled complication rates of CVA, AMI, CHF, and death were approximately 2.2 to 5.0 times higher among older patients who underwent colonoscopic polypectomy.

Conclusions

Elderly patients experienced approximately three times more GI and non-GI complications after EGD or colonoscopy than young patients. Physicians should pay attention to the potential risks of GI endoscopy in elderly patients.

Real-World Use of Colonoscopy in an Older Population: A Nationwide Standard Cohort Study Using a Common Data Model

BACKGROUNDS AND AIMS

Rapid population aging is considered to be a major factor in increased colonoscopy use in Korea. However, real-world use of colonoscopy in older populations is rarely evaluated using Korean databases.

METHODS

We conducted a retrospective, observational cohort study of individuals aged over 20 years between 2012 and 2017. We used the Health Insurance Review and Assessment-National Patient Samples database, previously converted to the standardized Observational Medical Outcomes Partnership-Common Data Model. The use of diagnostic colonoscopy and colonoscopic polypectomy was evaluated, stratified by age group and sex.

RESULTS

During the study period, we captured data from the database on 240,406 patients who underwent diagnostic colonoscopy and 88,984 who underwent colonoscopic polypectomy. During the study period, use of diagnostic colonoscopy and colonoscopic polypectomy steadily increased, but both procedures were most significantly increased in the 65- to 85-year group compared to other age groups (p < 0.05). Average ages for both procedures significantly increased in the most recent 3 years (p < 0.05). Polypectomy rates for men plateaued in the 50- to 64-year age group, but rates for women steadily increased up to the 65- to 85-year group. Polypectomy rates were higher for men than for women in all index years.

CONCLUSIONS

The use of diagnostic colonoscopy and colonoscopic polypectomy significantly increased in the 65- to 85-year age group. Our findings suggest that more available colonoscopy resources should be allocated to older populations, considering the aging society in Asian countries.

Pediatric Colonoscopic Polypectomy Technique

Colonoscopy with polypectomy is frequently performed in pediatric patients based on symptoms, with the majority of polyps identified being benign juvenile pedunculated polyps with a vascular stalk. This is in distinction to adults where polypectomy is often performed as part of a colon cancer screening and prevention strategy and a higher fraction of polyps are sessile and or dysplastic. In adults, polypectomy techniques emphasize a need for deeper resection to ensure complete resection of adenomas or potential carcinoma in situ. Adenomatous polyps can occur in the pediatric age group and may be associated with an underlying polyposis, hereditary or chronic inflammatory conditions. Polypectomy techniques include use of cold biopsy forceps for very small polyps, cold snare polypectomy for small sessile polyps and hot snare polypectomy for the majority of polyps in the pediatric age group. Adjuvant techniques include epinephrine volume reduction, saline-assisted polypectomy and hemostatic techniques including injection, clip application and loop application to prevent or treat post-polypectomy bleeding. Electrosurgical principles guide the settings and type of current utilized during hot snare polypectomy. Polypectomy utilizing thermal techniques is associated with a higher risk of complications compared with diagnostic colonoscopy.

ASGE review of adverse events in colonoscopy

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

Serrated lesions and serrated polyposis syndrome

The serrated pathway has been shown to be an alternative colorectal carcinogenetic route potentially accounting for up to one third of all CRCs. Serrated lesions, particularly SSPs, have been a focus of research during the past few years. They have well-established histological and molecular characteristics that account for their potential carcinogenetic risk through the accumulation BRAF, KRAS and methylator profile (CpG) mutations. Their endoscopic identification and resection represent a challenge because of their specific characteristics, and the need for an adequate specimen for histological diagnosis. Knowledge of these lesions is key, as is the adoption of established criteria for their endoscopic description and histological diagnosis. SPS is the maximum expression of involvement by serrated lesions, is associated with increased risk for CRC, and requires attentive endoscopic follow-up, as well as family screening. While the exact etiopathogenic mechanism remains unknown, current research will likely provide us with appropriate answers in the not too distant future.

Endoscopic management of mucosal lesions in the gastrointestinal tract

With the increasing role of endoscopy in patient evaluation, more mucosal lesions, including gastric, duodenal and colonic polyps, are encountered during routine examinations. It is imperative for gastroenterologists to become familiar with the endoscopic management of these various gastrointestinal lesions. In this article, various resection techniques will be discussed, including hot/cold forceps polypectomy, hot/cold snare polypectomy, endoscopic mucosal resection, and endoscopic submucosal dissection. The article will also discuss the evidence regarding the efficacy and safety of these techniques and the future direction of endoscopic management of mucosal lesions in the gastrointestinal tract.

Factors predicting adverse events associated with therapeutic colonoscopy for colorectal neoplasia: a retrospective nationwide study in Japan

BACKGROUND AND AIMS

Few large studies have evaluated the adverse events associated with therapeutic colonoscopy for colorectal neoplasia, including bleeding and bowel perforation. Our aim was to investigate factors associated with these events, using a Japanese national inpatient database.

METHODS

We extracted data from the nationwide Japan Diagnosis Procedure Combination database for patients who underwent therapeutic colonoscopy for colorectal neoplasia between 2013 and 2014. Therapeutic colonoscopy included endoscopic submucosal dissection (ESD), EMR, and polypectomy. Outcomes included bleeding, perforation, cerebro-cardiovascular events, and in-hospital death. A multivariable logistic regression model was used to evaluate factors associated with bleeding and bowel perforation.

RESULTS

We analyzed 345,546 patients, including 16,812 (4.9%) who underwent ESD, 219,848 (63.6%) who underwent EMR, and 108,886 (31.5%) who underwent polypectomy. The rates of bleeding, bowel perforation, cardiovascular events, cerebrovascular events, and death were 32.5, 0.47, 0.05, 0.88, and 1.32 per 1000 patients, respectively. In the multivariate analysis, a higher bleeding rate was associated with being male, comorbid diseases, ESD, tumor size ≥2 cm, and use of drugs including low-dose aspirin, thienopyridines, non-aspirin antiplatelet drugs, novel oral anticoagulants, warfarin, non-steroidal anti-inflammatory drugs (NSAIDs), and steroids. A higher bowel perforation rate was associated with being male, renal disease, ESD, tumor size ≥2 cm, and drugs including warfarin, NSAIDs, and steroids.

CONCLUSIONS

Although the incidence of adverse events after therapeutic colonoscopy was low, several patient-related factors were significantly associated with bleeding and bowel perforation.

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.

Knife-assisted snare resection (KAR) of large and refractory colonic polyps at a Western centre: Feasibility, safety and efficacy study to guide future practice

OBJECTIVE

Endoscopic mucosal resection (EMR) is widely practiced in western countries. Endoscopic submucosal dissection (ESD) is very effective for treating complex polyps but colonic ESD in the western setting remains challenging. We have developed a novel technique of knife-assisted snare resection (KAR) for the resection of these complex lesions. Here we aim to describe the technique, evaluate its outcomes, identify outcome predictors and define its learning curve.

METHODS

We conducted a prospective cohort study of patients who had large and refractory polyps resected by KAR at our institution from 2007 to 2013. Polyp characteristics and procedure details were recorded. Endoscopic follow-up was performed to identify recurrence.

RESULTS

A total of 170 patients with polyps 20-170 mm in size were treated by KAR and followed up for a mean of 31.5 months (range 12-84 months). 29% of the polyps were >50 mm, 22% had fibrosis from previous unsuccessful interventions and 25% were in the right colon. The perforation rate (1.2%) and bleeding rate (4.7%) were acceptable and managed conservatively in most patients. Recurrence rate after the first attempt was 13.1%. Recurrence was significantly increased by polyp size >50 mm (p = 0.008; OR 5.03, 95% CI 1.54-16.48), presence of fibrosis (p = 0.002; OR 6.59, 95% CI 1.97-22.07) and piecemeal resection (p < 0.001; OR 0.31, CI 0.078-1.12). Cure rates were 87% after the first attempt, improving to 95.6% with further attempts. En bloc resection rate showed a linear increase and reached almost 80% as the endoscopist's cumulative experience approached 100 cases.

CONCLUSION

This is the largest reported Western series on KAR in the colon. We have demonstrated the feasibility, efficacy and safety of this technique in the treatment of complex polyps, with or without fibrosis and at all sites. KAR has shown better outcomes than either EMR or ESD. We have also managed to identify significant outcome predictors and define the learning curve.

Post-polypectomy electrocoagulation syndrome: a rare cause of acute abdominal pain

While generally safe, the most feared complication of colonoscopy is perforation of the colon, occurring in nearly 1 in 1,000 procedures, and is more common when polypectomy is performed and electrocautery is used. Less commonly known is the post-polypectomy electrocoagulation syndrome, a transmural burn of the colon which mimics the signs and symptoms of perforation as well as the time course, but follows a benign course and can be treated conservatively.

Endoscopic polypectomy for pacemaker patients: is it safe?

BACKGROUND

Endoscopic polypectomy is believed to reduce the incidence of colorectal cancer, and it has become a standard practice for the removal of gastrointestinal polyps. However, for patients with implanted cardiac devices, endoscopic polypectomy is thought to be relatively contraindicated. Aside from two case reports from around 10 years ago, few studies have evaluated the safety of endoscopic polypectomy for this population. In this study, polypectomy was performed in 14 consecutive pacemaker patients to determine the safety of endoscopic polypectomy using high-frequency current in patients with implanted cardiac devices.

METHODS

Fourteen patients with gastrointestinal polyps and implanted cardiac devices were evaluated, and endoscopic polypectomy was performed. Continuous monitoring of heart rate, blood pressure, oxygen saturation and electrocardiographic tracing was conducted. A trained cardiologist was present during the procedures. At the end of the procedures, the cardiac devices were reinterrogated to check for any changes.

RESULTS

Our results showed that a total of 61 procedures in 14 patients were all successfully completed, and no abnormalities were identified during continuous monitoring. There were no statistically significant differences in the preoperation, intraoperation and postoperation data. None of the patients suffered any arrhythmias or functional disruption to their cardiac devices.

CONCLUSIONS

Endoscopic polypectomy using high-frequency current appears to be safe when performed in patients with pacemakers. However, larger multicentre studies are needed to confirm the safety of this procedure in this patient population.