Colonoscopic polypectomy

Rectus abdominis muscle abscess after performing colonoscopy-A case report

Endoscopic removal of premalignant polyps can prevent colorectal cancers. It is considered a safe procedure, yet there are some complications reported. Rectus abdominis muscle abscess (RAMA) is a type of pyomyositis seen as a complication of rectus sheath hematoma. Predisposing factors to RAMA include trauma, diabetes mellitus, alcohol abuse, Intravenous drug abuse and hematologic diseases.In this article, we report a case of a 74-year-old patient with abscess formation in the Rectus Abdominis muscle after colonoscopy and polypectomy with the application of abdominal pressure techniques without any early complications. Diagnosis of RAMA was made after a Computed Tomography scan and ultrasound-guided drainage, in addition to antibiotic therapy, were used as treatment.Although colonoscopy is considered a generally safe procedure, endoscopists should be aware of Rectus Abdominis sheath hemorrhage and RAMA in the following as a complication with the presentation of abdominal pain. Applying abdominal pressure should be done carefully To reduce minor trauma likelihood, owing to it being a predisposing factor of RAMA.

Endoscopic Management of Large Non-Pedunculated Colorectal Polyps

Large non-pedunculated colorectal polyps ≥20 mm (LNPCPs) comprise approximately 1% of all colorectal polyps. LNPCPs more commonly contain high-grade dysplasia, covert and overt cancer. These lesions can be resected using several means, including conventional endoscopic mucosal resection (EMR), cold-snare EMR (C-EMR) and endoscopic submucosal dissection (ESD). This review aimed to provide a comprehensive, critical and objective analysis of ER techniques. Evidence-based, selective resection algorithms should be used when choosing the most appropriate technique to ensure the safe and effective removal of LNPCPs. Due to its enhanced safety and comparable efficacy, there has been a paradigm shift towards cold-snare polypectomy (CSP) for the removal of small polyps (<10 mm). This technique is now being applied to the management of LNPCPs; however, further research is required to define the optimal LNPCP subtypes to target and the viable upper size limit. Adjuvant techniques, such as thermal ablation of the resection margin, significantly reduce recurrence risk. Bleeding risk can be mitigated using through-the-scope clips to close defects in the right colon. Endoscopic surveillance is important to detect recurrence and synchronous lesions. Recurrence can be readily managed using an endoscopic approach.

Complete polyp resection with cold snare versus hot snare polypectomy for polyps of 4-9 mm: a randomized controlled trial

BACKGROUND

Endoscopic screening with polypectomy reduces the incidence of colorectal cancer (CRC). Incomplete polyp removal may attenuate the effect of screening. This randomized trial compared cold snare polypectomy (CSP) with hot snare polypectomy (HSP) in terms of complete polyp resection.

METHODS

We included patients ≥ 40 years of age at eight hospitals in four countries who had at least one non-pedunculated polyp of 4-9 mm detected at colonoscopy. Patients were randomized 1:1 to CSP or HSP. Biopsies from the resection margins were obtained systematically after polypectomy in both groups. We hypothesized that CSP would be non-inferior to HSP, with a non-inferiority margin of 5 %. Logistic regression models were fitted to identify the factors explaining incomplete resection.

RESULTS

425 patients, with 601 polyps, randomized to either CSP or HSP were included in the analysis. Of 318 polyps removed by CSP and 283 polyps removed by HSP, 34 (10.7 %) and 21 (7.4 %) were incompletely resected, respectively, with an adjusted risk difference of 3.2 % (95 %CI -1.4 % to 7.8 %). There was no difference between the groups in terms of post-polypectomy bleeding, perforation, or abdominal pain. Independent risk factors for incomplete removal were serrated histology (odds ratio [OR] 3.96; 95 %CI 1.63 to 9.66) and hyperplastic histology (OR 2.52; 95 %CI 1.30 to 4.86) in adjusted analyses.

CONCLUSION

In this randomized trial, non-inferiority for CSP could not be demonstrated. Polyps with serrated histology are more prone to incomplete resection compared with adenomas. CSP can be used safely for small polyps in routine colonoscopy practice.

Underwater versus conventional cold snare polypectomy of colorectal polyps 4-9 mm in diameter: a prospective randomized controlled trial

BACKGROUND AND AIMS

Cold snare polypectomy (CSP) has been reported as safe and effective method for the removal of small colorectal polyps. However, some studies showed low R0 resection rate. Underwater endoscopic mucosal resection is an effective technique to increase the proportions of complete resection. Therefore, the aim was to compare the rate of R0 resection of colorectal polyps 4-9 mm in diameter between conventional CSP (C-CSP) and underwater CSP (U-CSP).

METHODS

This study was a prospective randomized controlled trial. A total of 198 polyps (4-9 mm) in 110 patients were enrolled between December 2019 and June 2020. The polyps were randomized to be treated with either C-CSP (100 polyps) or U-CSP (98 polyps).

RESULTS

The R0 resection rate was significantly higher in U-CSP group than in C-CSP groups (84.7% vs. 59.0%; p < 0.001). The polyp retrieval rate of C-CSP and U-CSP was 94.5% and 100% (p = 0.030). The rate of polyp fragmentation of C-CSP and U-CSP group was 5.3% and 0% (p = 0.027). The resection time and retrieval time were longer in C-CSP than U-CSP (45.0 ± 37.7 s vs. 34.1 ± 21.2 s, p = 0.032 and 51.9 ± 67.7 s vs. 12.7 ± 12.4 s, p < 0.001). No clinically significant bleeding or perforation occurred in either group.

CONCLUSIONS

The results of this study were excellent with U-CSP of 4-9 mm colorectal polyps in terms of R0 resection, polyp retrieval and fragmentation rate, and procedure/retrieval time. Therefore, U-CSP is a safe and effective technique for removing colorectal polyps 4-9 mm in diameter. KCT (0004530).

A Randomized Controlled Trial of Cold Snare Polypectomy Technique: Technique Matters More Than Snare Wire Diameter

INTRODUCTION

Cold snare polypectomy (CSP) is safe and effective for the removal of small adenomas (≤10 mm); however, reported incomplete resection rates (IRRs) vary. The optimal CSP technique, where a wide margin of normal tissue is resected around the target lesion, and snare design have both been hypothesized to reduce the IRR after CSP. We sought to investigate the efficacy of a thin-wire versus thick-wire diameter snare on IRR, using the standardized CSP technique.

METHODS

This was an international multicenter parallel design randomized trial with 17 endoscopists of varying experience (NCT02581254). Patients were randomized in a 1:1 ratio to the use of a thin-wire (0.30 mm) or thick-wire (0.47 mm) snare for CSP of small (≤10 mm) colorectal polyps. The primary end point was the IRR as determined by the histologic assessment of the defect margin after polypectomy.

RESULTS

Over 52 months to January 2020, 1,393 patients were eligible. A total of 660 patients with polyps (57.4% male) were randomized to a thin-wire (n = 339) or thick-wire (n = 321) snare. The overall IRR of the cohort was 1.5%. There was no significant difference in the IRR between the thin- and thick-wire arms; relative risk-0.41, 95% CI (0.11-1.56), P = 0.21. No significant differences were observed in the rate of adverse events.

DISCUSSION

In this multicenter randomized trial, CSP is safe and effective with very low rates of incomplete resection independent of the diameter of the snare wire used. This suggests that the optimal operator technique is more important than the snare design alone in minimizing residual adenoma after CSP.

Impact of technical innovations in EMR in the treatment of large nonpedunculated polyps involving the ileocecal valve (with video)

BACKGROUND AND AIMS

The endoscopic management of large nonpedunculated colorectal polyps involving the ileocecal valve (ICV-LNPCPs) remains challenging because of its unique anatomic features, with long-term outcomes inferior to LNPCPs not involving the ICV. We sought to evaluate the impact of technical innovations and advances in the EMR of ICV-LNPCPs.

METHODS

The performance of EMR for ICV-LNPCPs was retrospectively evaluated in a prospective observational cohort of LNPCPs ≥20 mm. Efficacy was measured by clinical success (removal of all polypoid tissue during index EMR and avoidance of surgery) and recurrence at first surveillance colonoscopy. Accounting for the adoption of technical innovations, comparisons were made between an historical cohort (September 2008 to April 2016) and contemporary cohort (May 2016 to October 2020). Safety was evaluated by documenting the frequencies of intraprocedural bleeding, delayed bleeding, deep mural injury, and delayed perforation.

RESULTS

Between September 2008 to October 2020, 142 ICV-LNPCPs were referred for EMR. Median ICV-LNPCP size was 35 mm (interquartile range, 25-50 mm). When comparing the contemporary (n = 66) and historical cohorts (n = 76) of ICV-LNPCPs, there were significant differences in clinical success (93.9% vs 77.6%, P = .006) and recurrence (4.6% vs 21.0%, P = .019).

CONCLUSIONS

With technical advances, ICV-LNPCPs can be effectively and safely managed by EMR, independent of lesion complexity. Most patients experience excellent outcomes and avoid surgery.

The quality of colorectal polypectomy. Is it enough to have just a visual assessment of the site?

INTRODUCTION

Performing a colonoscopy allows the examination of the entire colon and the assessment of polyps.

PATIENTS, MATERIALS AND METHODS

We performed a retrospective analysis of prospectively collected data from January 2018 until February 2020 (two years), in which we enrolled a number of 210 patients performing colonoscopy in the Research Center of Gastroenterology and Hepatology, University of Medicine and Pharmacy of Craiova, Romania. We performed 326 polypectomies.

RESULTS

We classified the polyps into diminutive (n=169), small (n=103) and large polyps (n=54). Regarding the polypectomy technique, our results indicated that 40 out of 48 (83.3%) polypectomies with the biopsy forceps were complete, as well as 27 out of 31 (87.1%) cold snare polypectomies and 12 out of 14 (85.7%) hot snare polypectomies. The differences were not statistically significant (p=0.116). Regarding the number of incomplete polypectomies, our data suggests that the high expertise endoscopist had two incomplete resections (5.1% of total), the medium expertise endoscopist 1 had also two incomplete resections (11.1% of total), the medium expertise endoscopist 2 had three incomplete resections (15% of total), the limited expertise endoscopist 1 had three incomplete resections (27.27% of total) and the limited expertise endoscopist 2 had four incomplete resections (30.76% of total). Analyzing the data, the differences were statistically significant (p=0.006).

CONCLUSIONS

Our study is able to suggest that high-definition white-light endoscopy (HD-WLE) macroscopic visualization of the polyp resection site is not enough to assess complete polyp resection and follow-up colonoscopy should be performed for cases with incomplete margins of resection.

Effects of age, sex and pathological type on the risk of multiple polyps: A Chinese teaching hospital study

OBJECTIVES

The lack of risk profile data on changes in multiple polyps identified by a colonoscopy constrains the creation of evidence-based guidelines. Our study aimed to investigate the relationship between size, location and histology of multiple polyps and patients' characteristics in a large teaching hospital-based Chinese population.

METHODS

We conducted a large, case-control, retrospective analysis on polyps obtained from 8308 patients who presented at the Digestive Endoscopy Center, Changhai Hospital (Shanghai, China) from January 2013 to August 2015. In total 10572 polyps were analyzed, with risk factors extrapolated through chart reviews of patients' electronic medical records.

RESULTS

Single polyps were identified in 6843 (82.4%) patients while multiple polyps were found in 1465 (17.6%). A multivariate analysis indicated that men were more likely than women to have multiple polyps (P < 0.001). Compared with the single polyps group, the numbers of patients with multiple polyps increased significantly with age (P < 0.001). Multiple small (6-9 mm) non-advanced adenomas were more likely to be found than were diminutive (<5 mm) non-advanced adenomas (P < 0.001). While most advanced and non-advanced adenomas were diagnosed in patients with single adenomas (55.9% and 65.6%, respectively), advanced adenomas were more likely than non-advanced adenomas to be in multiples (P < 0.001).

CONCLUSIONS

Our data indicate that particular features of colorectal polyps, such as their large size, advanced histology, together with patients' characteristics, including their sex and age, are risk factors associated with multiple polyps during diagnosis, screening and surveillance.

Efficacy and safety of cap-assisted endoscopic mucosal resection of ileocecal valve polyps

Background and study aims  Standard endoscopic mucosal resection (EMR) of ileocecal valve (ICV) polyps is challenging. Cap-assisted endoscopic mucosal resection (C-EMR) can be performed when polyps are not easily amenable to standard EMR. Current literature is limited regarding its efficacy and safety for ICV polyps. The objectives of this study were to assess the efficacy and safety of C-EMR for ICV polyps. Patients and methods  A retrospective review was conducted from September 2008 to November 2018 at a tertiary care center. Patients included in the study underwent C-EMR for ICV polyps by a single gastroenterologist (LHJ). Polyps were successfully eradicated if they were removed en-bloc as confirmed by pathology, or had a negative biopsy on follow-up colonoscopy. Outcomes of the procedures were evaluated, including complete adenoma clearance and adverse events. Results  Twenty-one ICV polyps were removed with C-EMR. Median polyp size was 15 mm (range, 5-45). The rate of complete adenoma clearance was 100 %. Procedure-related complications occurred in five patients (24 %): delayed GI bleeding (4.8 %) and deep mucosal resection/visible vessel (14.3 %). Three patients had subsequent surveillance colonoscopies at 8, 56, and 67 months, respectively. The third patient was found to have a 6-mm flat polyp at the edge of the previous polypectomy site. This was treated with C-EMR and repeat colonoscopy 6 months later did not show residual. Conclusion  C-EMR is highly effective in treating ICV polyps with a low complication rate. It is our suggested method in approaching ICV polyps that are difficult to remove via standard freehand snare EMR technique.

Volatile organic compounds in breath can serve as a non-invasive diagnostic biomarker for the detection of advanced adenomas and colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer diagnosis in the Western world.

AIM

To evaluate exhaled volatile organic compounds (VOCs) as a non-invasive biomarker for the detection of CRC and precursor lesions using an electronic nose.

METHODS

In this multicentre study adult colonoscopy patients, without inflammatory bowel disease or (previous) malignancy, were invited for breath analysis. Two-thirds of the breath tests were randomly assigned to develop training models which were used to predict the diagnosis of the remaining patients (external validation). In the end, all data were used to develop final-disease models to further improve the discriminatory power of the algorithms.

RESULTS

Five hundred and eleven breath samples were collected. Sixty-four patients were excluded due to an inadequate breath test (n = 51), incomplete colonoscopy (n = 8) or colitis (n = 5). Classification was based on the most advanced lesion found; CRC (n = 70), advanced adenomas (AAs) (n = 117), non-advanced adenoma (n = 117), hyperplastic polyp (n = 15), normal colonoscopy (n = 125). Training models for CRC and AAs had an area under the curve (AUC) of 0.76 and 0.71 and blind validation resulted in an AUC of 0.74 and 0.61 respectively. Final models for CRC and AAs yielded an AUC of 0.84 (sensitivity 95% and specificity 64%) and 0.73 (sensitivity and specificity 79% and 59%) respectively.

CONCLUSIONS

This study suggests that exhaled VOCs could potentially serve as a non-invasive biomarker for the detection of CRC and AAs. Future studies including more patients could further improve the discriminatory potential of VOC analysis for the detection of (pre-)malignant colorectal lesions. (https://clinicaltrials.gov Identifier NCT03488537).

A novel technique of endoscopic submucosal dissection for circumferential ileocecal valve adenomas with terminal ileum involvement: the "doughnut resection" (with videos)

BACKGROUND

Ileocecal valve (ICV) lesions are difficult to resect endoscopically and patients are often referred for laparoscopic colectomy. ICV involvement has been shown to be related to technical failure and tumor recurrence after endoscopic mucosal resection (EMR) and represents a challenge for endoscopic submucosal dissection (ESD). Few publications have focused specifically on endoscopic management of ICV lesions.

METHODS

We developed a novel ESD technique, the "doughnut resection," for circumferential ICV adenomas with terminal ileum involvement. Two circumferential mucosal incisions are performed, one in the ileum and the other in the cecum, followed by submucosal dissection of the disk of tissue between the two incisions around a guiding stent placed across the valve that helps guide the dissection as it crosses the valve orifice. The lesion is removed en bloc in the shape of a "doughnut" with two concentric assessable lateral margins. The underwater ESD technique and a gastroscope were used to facilitate the resection.

RESULTS

Seven patients received the doughnut resection. The median patient age was 67 years. All patients had prior biopsy and three had prior endoscopic resection (1-6 times). The median specimen diameter was 4.5 cm (range 3-8). All resections were en bloc and R0. There was no perforation, delayed bleeding, or other clinically significant adverse events. After a median follow-up of 21 months (range 12-32), there was no tumor recurrence.

CONCLUSION

The "doughnut resection" is a feasible, safe, and effective method to remove circumferential ICV lesions endoscopically even for patients with multiple prior tumor manipulations.

Practice patterns and predictors of prophylactic endoscopic clip usage during polypectomy

Background and study aims  Prophylactic endoscopic clips are commonly placed during polypectomy to reduce risk of delayed bleeding, although evidence to support this practice is unclear. Our study aimed to: (1) identify variables associated with prophylactic clip use; (2) explore variability between endoscopists' clipping practices and (3) study temporal trends in prophylactic clip use. Patients and methods  This was a retrospective cohort study in a high-volume unit dedicated to screening-related colonoscopies. Colonoscopies involving polypectomy from 2008 to 2014 were reviewed. The primary outcome was prophylactic clipping status, both at the patient level and per polyp. Hierarchical regression models yielded adjusted odds ratios (AORs) to determine predictors of prophylactic clipping. Results  A total of 8,366 colonoscopies involving 19,129 polypectomies were included. Polyp size ≥ 20 mm was associated with higher clip usage (AOR 2.94; 95 % CI: 2.43, 3.54) compared to polyps < 10 mm. Right-sided polyps were more likely to be clipped (AOR 2.78; 95 % CI: 2.34, 3.30) relative to the rectum. Surgeons clipped less than gastroenterologists (OR 0.52; 95 % CI: 0.44, 0.63). From 2008 to 2014, the crude proportion of prophylactically clipped cases increased by 7.4 % (95 % CI: 7.1, 7.6) from 1.9 % to 9.3 %. Significant inter-endoscopist variability in clipping practices was observed, notably, for polyps < 10 mm. Conclusions  Prophylactic clip usage was correlated with established risk factors for delayed bleeding. Significantly increased clip usage over time was shown. Given that evidence does not clearly support prophylactic clipping, there is a need to educate practitioners and limit healthcare resource utilization.

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.

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.

Colonoscopy, Polypectomy, and the Risk of Bleeding

Colonoscopy with polypectomy is the means by which the incidence of colon cancer may be reduced; however, polypectomy is not without risk. Physicians must carefully weigh the risks and benefits of colonoscopy, particularly when patients are given prescriptions for antiplatelet agents and anticoagulants. This article discusses the risks of colonoscopy and polypectomy and reviews the most recent data for managing antiplatelet agents and anticoagulants in the periendoscopic period.

Postpolypectomy Bleeding Prevention and More Complete Precancerous Colon Polyp Removal With Endoscopic Mucosal Stripping (EMS)

Background and Aims: Postpolypectomy bleeding and incomplete polyp removal are important complication and quality concerns of colonoscopy for colon cancer prevention. We investigated if endoscopic mucosal stripping (EMS) as a technical modification of traditional cold snare polypectomy to avoid submucosal injury during removal of non-pedunculated colon polyps could prevent postpolypectomy bleeding and facilitate complete polyp removal.

Methods: This is an Internal Review Board exemption-granted retrospective analysis of 5,142 colonoscopies with snare polypectomy performed by one of the authors (ZJC) at Minnesota Gastroenterology ambulatory endoscopy centers during a 12-year period divided into pre-EMS era (2005–2012, n = 2,973) and EMS era (2013–2016, n = 2169) with systemic adoption of EMS starting 2013. Change in postpolypectomy bleeding rate before and after EMS adoption and EMS polypectomy completeness were evaluated.

Results: Zero postpolypectomy bleeding case was found during EMS era (rate 0%) compared with 10 bleeding cases during pre-EMS era (rate 0.336%). This difference was statistically significant (P = 0.0055) and remained so after excluding 2 bleeding cases of pedunculated polyps (P = 0.012). All bleeding cases involved hot snare polypectomy. Histological examination of the involved polyps showed substantial submucosal vascular damage in contrast to a remarkable paucity of submucosa in comparable advanced polyps removed using EMS. Both biopsy and follow-up colonoscopy examination of the polypectomy sites confirmed that EMS more completely removed non-pedunculated advanced polyps.

Conclusions: EMS polypectomy was effective in preventing postpolypectomy bleeding and facilitated complete polyp removal.

Novel evaluation method for electrosurgical ablation by monopolar hot biopsy forceps for colonoscopy

Aim

This study evaluates tissue injury, which results from electrosurgical ablation, by correlating lesion depth to tissue impedance, and introduces a newly developed real-time feedback control system that can be applied for preventing excessive tissue injury. Although some previous studies had evaluated such tissue injuries in other ways, a specific mechanism is necessary to actually prevent excessive tissue injury.

Materials and methods

Ablation tests were performed by using an impedance bridge circuit and gel block that have been developed in two previous studies. Depth of the ablation site was measured with the use of a laser displacement measurement device. To simplify the programing work, voltage was used, as a substitution of tissue impedance, to evaluate tissue injury.

Results

The depth of the ablation site was found to increase with either increased power setting or ablation duration, and the depth was analyzed to investigate correlation with measured voltage. The real-time feedback control system was developed by achieving communication between LabVIEW and an Arduino microcontroller.

Conclusion

It is concluded that the depth of the ablation site modestly correlates with the measured voltage under specific conditions, and the newly developed system fulfills the goal of the design.

Histological Comparison of Cold versus Hot Snare Resections of the Colorectal Mucosa

BACKGROUND

Delayed postpolypectomy bleeding occurs more frequently after hot resection than after cold resection.

OBJECTIVE

To elucidate the underlying mechanism, we performed a histological comparison of tissue after cold and hot snare resections.

DESIGN

This is a prospective study, registered in the University Hospital Medical Information Network (UMIN000020104).

SETTING

This study was conducted at Aizu Medical Center, Fukushima Medical University, Japan.

PATIENTS

Fifteen patients scheduled to undergo resection of colorectal cancer were enrolled.

INTERVENTION

On the day before surgery, 2 mucosal resections (hot and cold) of normal mucosa were performed on each patient using the same snare without saline injection. The difference was only the application of electrocautery or not. Resection sites were placed close to the cancer to be included in the surgical specimen.

MAIN OUTCOME MEASURES

The primary outcome measure was the depth of destruction. Secondary outcome measures included the width of destruction, depth of the remaining submucosa, and number of vessels remaining at the resection sites. The number and diameter of vessels in undamaged submucosa were also evaluated.

RESULTS

All cold resections were limited to the shallow submucosa, whereas 60% of hot resections advanced to the deep submucosa and 20% to the muscularis propria (p < 0.001). There was no significant difference in the width of destruction. The number of remaining large vessels after hot resections trended toward fewer (p = 0.15) with a decreased depth of remaining submucosa (p = 0.007). In the deep submucosa, the vessel diameter was larger (p < 0.001) and the number of large vessels was greater (p = 0.018).

LIMITATIONS

Histological assessment was not blinded to the 2 reviewers. Normal mucosa was used instead of adenomatous tissue.

CONCLUSIONS

Hot resection caused damage to deeper layers involving more large vessels. This may explain the mechanism for the reduced incidence of hemorrhage after cold snare polypectomy. See Video Abstract at http://links.lww.com/DCR/A631.

Delayed Bleeding Following Cold Snare Polypectomy for Small Colorectal Polyps in Patients Taking Antithrombotic Agents

BACKGROUND

This study compared the incidence of delayed bleeding following 2 methods of cold snare polypectomy for colorectal polyps in patients taking antithrombotic agents.

METHODS

Patients undergoing cold snare polypectomy for colorectal polyps ≤10 mm without discontinuation of antithrombotic agents were enrolled. This was a retrospective study of a prospectively collected cohort based on a historical comparison of 2 time periods. A traditional cold snare was used between January 2012 and December 2013 and a dedicated cold snare was used between January 2014 and December 2015. Patients' and polyps' characteristics, antithrombotic agents used, the snare used, the number of clips used, and adverse events were documented from a hospital online database. Delayed bleeding was defined as bleeding that required endoscopic treatment within 2 weeks after polypectomy. The submucosal layer of the resected polyps (6 to 10 mm) was histologically examined for the presence of injured arteries.

RESULTS

A total of 172 patients having 370 eligible polyps were enrolled; traditional cold snare group, N=100 (212 polyps) and dedicated cold snare group, N=72 (158 polyps). The patients' and polyps' characteristics were similar between the 2 groups. Hemostatic clips were used more often with the traditional than dedicated cold snares [33/100 (33%) vs. 13/72 (18%), P=0.044]. Delayed bleeding following cold snare polypectomy occurred in 1.2% (2/172); 0% (0/72) with dedicated snare versus 2% (2/100) with the traditional snare (P=0.63). The presence of histologically demonstrated injured submucosal arteries with the dedicated cold snare was significantly less than with the traditional cold snare [4.1% (4/98) vs. 16% (17/105), P=0.009].

CONCLUSIONS

Colorectal polyps ≤10 mm can be removed without an increase in delayed bleeding using dedicated cold snare polypectomy in patients taking antithrombotic agents.

Polypectomy techniques among gastroenterologists in Norway - a nationwide survey

BACKGROUND AND STUDY AIMS

 Incomplete polyp removal has been estimated to cause 27 % of all colorectal cancers detected soon after colonoscopy. There is limited information regarding polypectomy techniques among endoscopists. The article is a nationwide survey of polypectomy techniques among Norwegian endoscopists.

MATERIALS AND METHODS

 We invited all board-certified gastroenterologists in Norway to complete a web-based questionnaire about their polypectomy technique. Inadequate polypectomy techniques were defined as using biopsy forceps for polyps larger than 3 mm in diameter, using hot biopsy forceps for polypectomy, and using the same electrocautery output irrespective of polyp size and morphology.

RESULTS

Twenty-six of 30 Norwegian gastroenterology departments participated in the study. A total of 119 endoscopists received the survey, and 70 (59 %) responded. Mean duration of endoscopy practice was 11.5 years, and 95 % had performed more than 1,000 colonoscopies during their career. Twenty-eight endoscopists (40 %) used one or more inadequate polypectomy techniques: 10 (14.3 %) used biopsy forceps for removal of polyps larger than 3 mm in diameter, five (7.1 %) used hot biopsy for polypectomy, and 17 (24 %) used the same electrocautery output for all polypectomies. Five (7 %) endoscopists reported that they did not remove polyps smaller than 4 mm.

CONCLUSION

 A substantial number of Norwegian endoscopists use inadequate polypectomy techniques. Improved training and certification of endoscopists is warranted.

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.

Efficacy and safety of cold snare resection in preventive screening colonoscopy

BACKGROUND AND AIM

 Removal of polyps during colonoscopy effectively prevents the development of colorectal cancer. So far, snare resection with high frequency current with or without prior submucosal saline injection is the method of choice. The aim of this study was to evaluate the feasibility, safety, and outcome of cold snare resection during routine endoscopy.

METHODS

 In this prospective study, 522 patients undergoing outpatient colonoscopy were included. Cold snare resection for diminutive (< 6 mm), small (6 - 9 mm), and larger polyps (> 9 - 15 mm) was performed using a dedicated cold snare device (Exacto ^® ) without prior submucosal injection. Outcome parameters included bleeding rate, perforation rate, procedure time, histologic evaluation of polyp margins, and success rates. The data were compared to a group of patients undergoing hot snare resection.

RESULTS

 Overall, 1233 polyps were removed using cold snare resection with an overall success rate of 99.4 %. All failures of cold snare resection occurred in the cecum (8/82, failure rate 9.8 %). In the remaining colon, the success rate was 100 %. Immediate post-polypectomy bleeding occurred in 0.49 % of all patients and was most frequently seen in polyps larger than 9 mm. The procedure time was significantly shorter using cold snare resection compared with hot snare resection (27.6 min vs. 35.7 min, P  < 0.01).

CONCLUSION

 Cold snare resection can be performed safely in outpatients for removal of small polyps in screening colonoscopy. It does not require prior saline injection and reduces procedure time without an increased risk of bleeding.

Role of the cold biopsy technique in diminutive and small colonic polyp removal: a systematic review and meta-analysis

BACKGROUND AND AIMS

The most commonly detected polyps during screening colonoscopy are diminutive and small polyps, and therefore endoscopic treatment of those polyps is a daily routine for every colonoscopist. The primary aim of this study was to compare the complete eradication rate of diminutive and small colorectal polyps using cold biopsy versus other techniques, because randomized controlled trials have shown conflicting results.

METHODS

In March 2015 we searched for randomized controlled trials in Medline, EMBASE, and ISI the Web of Science, starting with their dates of inception, and abstracts of pertinent scientific meetings (eg, American College of Gastroenterology, Digestive Disease Week). The primary outcome was complete removal of diminutive and small polyps (≤7 mm) by histologic eradication rates. The secondary outcome was total procedure time. Using RevMan (Cochrane), we used the Mantel-Haenszel random effects model for binary endpoints and the inverse variance method for continuous outcomes. Grading of Recommendations Assessment, Development and Evaluation was used to rate the quality of evidence for each outcome.

RESULTS

Five randomized controlled trials included a total of 668 patients and 721 polyps. Removal techniques included cold biopsy, jumbo biopsy, and cold snare polypectomy. Based on histologic criteria, incomplete polyp removal was significantly lower with cold snare/jumbo forceps biopsy technique than with the cold biopsy technique (relative risk, .40; 95% CI, .26-.62), with no heterogeneity (I(2), 0%). Total procedure time was an average of 2.66 minutes shorter for the cold snare/jumbo forceps biopsy techniques compared with the cold biopsy technique (95% CI, -5.14 to -.18). The quality of evidence was rated moderate.

CONCLUSIONS

There is moderate quality evidence that cold snare or jumbo biopsy techniques reduce the risk of incomplete diminutive polyp removal by 60% without increasing the total procedure time. Adequately powered randomized clinical trials are warranted to confirm these findings.

Do We Perform a Perfect Endoscopic Hemostasis Prophylactically with Argon Plasma Coagulation in Colonic Endoscopic Mucosal Resection?

BACKGROUND

Submucosal injection for endoscopic mucosal resection (EMR) may effect performing the prophylactic argon plasma coagulation (APC) of non-bleeding visible vessels on ulcer crater.

AIMS

The purpose of this study was to evaluate the clinical features of visible vessels in iatrogenic ulcers over time after prophylactic APC in colonic EMR.

PATIENTS AND METHODS

This study was designed as a prospective study. Between August and November 2013, a total of 40 patients who were admitted underwent prophylactic APC for non-bleeding visible vessels after colonic EMR. After confirming whether visible vessels were completely coagulated or not, the number of visible vessels in ulcers was counted over a specific time period, e.g. 1, 3, 5, or 7 min.

RESULTS

The mean number of visible vessels was significantly higher at 5 min (0.85 ± 1.14) after EMR with prophylactic APC compared to 1 and 3 min (1 min: 0.28 ± 0.60, P < 0.001; 3 min: 0.65 ± 0.87, P = 0.02) and there was no significant difference between 5 and 7 min (P = 0.31). Multivariate analysis showed that the size of the iatrogenic ulcer after EMR was associated with the occurrence of visible vessels (ulcer size >1 vs. ≤0.5 cm: OR 27.32, 95% CI 2.86-infinity).

CONCLUSIONS

A 5-min observation of the ulcer may be advantageous for the assessment of visible vessels after performing colonic EMR with prophylactic APC, and large (>1 cm) iatrogenic ulcers were associated with the occurrence of visible vessels after colonic EMR.

Cold snare piecemeal resection of colonic and duodenal polyps ≥1 cm

BACKGROUND

Endoscopic removal of duodenal and colorectal adenomas is currently considered to be the standard of care for prevention of adenocarcinoma. The use of cautery carries a risk of delayed bleeding, post-polypectomy syndrome, and perforation. We examined the safety and feasibility of removing colonic and duodenal polyps ≥ 1 cm using a piecemeal cold snare polypectomy technique.

PATIENTS

The study included 15 patients with duodenal polyps ≥ 1 cm and 15 patients with colonic polyps ≥ 1 cm.

MAIN OUTCOME MEASUREMENTS

Bleeding, perforation, abdominal pain, or hospitalization occurring within 2 weeks of polypectomy.

RESULTS

Between 24 August 2011 and 29 April 2013, 15 patients had removal of duodenal polyps ≥ 1 cm. Mean patient age was 64 years and 9/15 patients were male. The mean polyp size was 24 mm (10 - 60 mm). All polyps were removed with a cold snare and some required cold biopsy forceps. One patient required hospitalization for gastrointestinal blood loss 7 days post-polypectomy; this patient was using Coumadin. Between 27 February 2012 and 30 May 2013, 15 patients underwent resection of a ≥ 1 cm colonic polyp. Mean patient age was 68 years and 9/15 were male. The mean polyp size was 20 mm (10 - 45 mm). All polyps were primarily removed with a cold snare. None of the patients required hemostatic clips for control of immediate bleeding. One patient presented to the emergency department with abdominal pain 1 day after initial endoscopy. CT scan showed no abnormalities and the patient was discharged.

CONCLUSIONS

Cold snare polypectomy for large duodenal and colonic polyps is technically feasible and may have a favorable safety profile compared to standard electrocautery-based endoscopic resection. Comparative trials are required to determine the relative safety and efficacy of cold snare techniques for complete and durable resection of large polyps compared to standard hot snare methods.

Risk factors for incomplete polyp resection during colonoscopic polypectomy

Background/Aims

Colonoscopic polypectomy is highly efficient in preventing colorectal cancer, but polyps may not always be completely removed. Improved knowledge of the risk factors for incomplete polyp resection after polypectomy may decrease the cancer risk and additional costs. The aim of this study was to investigate the conditions that can cause incomplete polyp resection (IPR) after colonoscopic polypectomy.

Methods

A total of 12,970 polyps that were removed by colonoscopic polypectomy were investigated. Among them, we identified 228 cases with a positive resection margin and 228 controls with a clear resection margin that were matched for age, gender, and polyp size. We investigated the location, morphology, and histological type of the polyps and evaluated the skills of the endoscopist and assisting nurse.

Results

Multivariate analysis revealed that the polyps, which were located in the proximal part of the colon and rectum, were at significant risk of IPR. Histologically, an advanced polyp and an inexperienced assistant were also independent risk factors for IPR.

Conclusions

Polypectomy should be performed more carefully for polyps suspected to be cancerous and polyps located in the proximal part of the colon or rectum. A systematic training program for inexperienced assistants may be needed to decrease the risk of IPR.

Acute appendicitis following endoscopic mucosal resection of cecal adenoma

Endoscopic mucosal resection (EMR) allows the removal of flat or sessile lesions, laterally spreading tumors, and carcinoma of the colon or the rectum limited to the mucosa or the superficial submucosa. Acute appendicitis is the most common abdominal emergency requiring emergency surgery, and it is also a rare complication of diagnostic colonoscopy and therapeutic endoscopy, including EMR. In the case presented here, a 53-year-old female underwent colonoscopy due to a positive fecal occult blood test and was diagnosed with cecal adenoma. She was referred to our hospital and admitted for treatment. The patient had no other symptoms. EMR was performed, and 7 h after the surgery, the patient experienced right -lower abdominal pain. Laboratory tests performed the following day revealed a WBC count of 16000/mm³, a neutrophil count of 14144/mm³, and a C-reactive protein level of 2.20 mg/dL, indicating an inflammatory response. Computed tomography also revealed appendiceal wall thickening and swelling, so acute appendicitis following EMR was diagnosed. Antibiotics were initiated leading to total resolution of the symptoms, and the patient was discharged on the sixth post-operative day. Pathological analysis revealed a high-grade cecal tubular adenoma. Such acute appendicitis following EMR is extremely rare, and EMR of the cecum may be a rare cause of acute appendicitis.

Cold snare polypectomy versus cold forceps polypectomy for diminutive and small colorectal polyps: a randomized controlled trial

BACKGROUND

The optimal technique for removal of diminutive or small colorectal polyps is debatable.

OBJECTIVE

To compare the complete resection rates of cold snare polypectomy (CSP) and cold forceps polypectomy (CFP) for the removal of adenomatous polyps ≤7 mm.

DESIGN

Prospective randomized controlled study.

SETTING

A university hospital.

PATIENTS

A total of 139 patients who were found to have ≥1 colorectal adenomatous polyps ≤7 mm.

INTERVENTIONS

Polyps were randomized to be treated with either CSP or CFP. After the initial polypectomy, additional EMR was performed at the polypectomy site to assess the presence of residual polyp tissue.

MAIN OUTCOME MEASUREMENTS

Absence of residual polyp tissue in the EMR specimen of the polypectomy site was defined as complete resection.

RESULTS

Among a total of 145 polyps, 128 (88.3%) were adenomatous polyps. The overall complete resection rate for adenomatous polyps was significantly higher in the CSP group compared with the CFP group (57/59, 96.6% vs 57/69, 82.6%; P = .011). Although the complete resection rates for adenomatous polyps ≤4 mm were not different (27/27, 100% vs 31/32, 96.9%; P = 1.000), the complete resection rates for adenomatous polyps sized 5 to 7 mm was significantly higher in the CSP group compared with the CFP group (30/32, 93.8% vs 26/37, 70.3%; P = .013).

LIMITATIONS

Single-center study.

CONCLUSION

CSP is recommended for the complete resection of colorectal adenomatous polyps ≤7 mm. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01665898.).

Advances, problems, and complications of polypectomy

The major role of colonoscopy with polypectomy in reducing the incidence of and mortality from colorectal cancer has been firmly established. Yet there is cause to be uneasy. One of the most striking recent findings is that there is an alarmingly high incomplete polyp removal rate. This phenomenon, together with missed polyps during screening colonoscopy, is thought to be responsible for the majority of interval cancers. Knowledge of serrated polyps needs to broaden as well, since they are quite often missed or incompletely removed. Removal of small and diminutive polyps is almost devoid of complications. Cold snare polypectomy seems to be the best approach for these lesions, with biopsy forcep removal reserved only for the tiniest of polyps. Hot snare or hot biopsy forcep removal of these lesions is no longer recommended. Endoscopic mucosal resection and endoscopic submucosal dissection have proven to be effective in the removal of large colorectal lesions, avoiding surgery in the majority of patients, with acceptably low complication rates. Variants of these approaches, as well as new hybrid techniques, are being currently tested. In this paper, we review the current status of the different approaches in removing polypoid and nonpolypoid lesions of the colon, their complications, and future directions in the prevention of colorectal cancer.

A prospective comparative study of blended and pure coagulation current in endoscopic mucosal resection of large sessile colorectal polyps

BACKGROUND

The aim of this study was to compare pure coagulation and blended current in the resection of large colorectal sessile polyps (SPs).

PATIENTS AND METHODS

Between January 2009 and June 2012, 84 patients (45 men, 39 women; median age 66 y; range, 42 to 88 y) with large colorectal SPs (diameter ≥2 cm) were randomized in 1:1 ratio to undergo treatment by the "lift and cut" piecemeal resection technique. A total of 43 blended current subjects (group A) were well matched to 41 pure coagulation current subjects (group B), with a median lesion size of 3.9 cm (group A, 3.7 vs. group B, 4.2 cm; P=0.316), respectively. The rate of complications, the factors that predict complications, and the recurrence of adenoma were analyzed.

RESULTS

Complete macroscopic resection was achieved in 39 patients (90.7%) of group A and in 36 patients (87.6%) of group B (P=0.735). Argon plasma coagulation at resection's margins was performed in 10 patients (23.2%) of group A and in 14 patients (34.1%) of group B (P=0.269). Eight patients (9.5%) [group A, n=3 patients (7.1%) vs. group B, n=5 patients (12%); P=0.756] developed immediate (4) or delayed (4) bleeding. Four patients with bleeding were under treatment with selective serotonin reuptake inhibitors. All bleedings were successfully treated conservatively or with endoclipping and heater probe application. Perforation occurred in 1 patient of each group and was managed by clips closure and antibiotics and right hemicolectomy, respectively. Postpolypectomy syndrome was observed in 2 patients (4.6%) of group A and 3 patients (7.3%) of group B (P=0.834). In 3 patients, the histopathologic analysis of resected SPs revealed invasive carcinoma, and surgical resection was performed in 1 patient. Two patients refused operation. Among the patients who underwent follow-up surveillance colonoscopy, a total recurrence rate of 25.67% of adenomas with no difference was observed between the 2 groups [group A, n=8 patients (21.6%) vs. group B, n=11 patients (31.4%); P=0.345]. Recurrence of adenoma was observed in 12 patients (16.22%) without and in 7 patients (9.46%) with argon plasma coagulation treatment.

CONCLUSIONS

No difference was found in the rate of complications between the 2 types of current used in the resection of large colorectal SPs. However, an influence of selective serotonin reuptake inhibitors on postpolypectomy bleeding was observed, which deserves further investigation.

Removal of small colorectal polyps in anticoagulated patients: a prospective randomized comparison of cold snare and conventional polypectomy

BACKGROUND

The bleeding risk after cold snare polypectomy in anticoagulated patients is not known.

OBJECTIVE

To compare the bleeding risk after cold snare polypectomy or conventional polypectomy for small colorectal polyps in anticoagulated patients.

DESIGN

Prospective randomized controlled study.

SETTING

Municipal hospital in Japan.

INTERVENTIONS

Anticoagulated patients with colorectal polyps up to 10 mm in diameter were enrolled. Patients were randomized to polypectomy with either cold snare technique (Cold group) or conventional polypectomy (Conventional group) without discontinuation of warfarin. The primary outcome measure was delayed bleeding (ie, requiring endoscopic intervention within 2 weeks after polypectomy). Secondary outcome measures were immediate bleeding and retrieval rate of colorectal polyps.

RESULTS

Seventy patients were randomized (159 polyps): Cold group (n = 35, 78 polyps) and Conventional group (n = 35; 81 polyps). The patients' demographic characteristics including international normalized ratio and the number, size, and shape of polyps removed were similar between the 2 techniques. Immediate bleeding during the procedure was more common with conventional polypectomy (23% [8/35]) compared with cold polypectomy (5.7% [2/35]) (P = .042). No delayed bleeding occurred in the Cold group, whereas 5 patients (14%) required endoscopic hemostasis in the Conventional group (P = .027). Complete polyp retrieval rates were identical (94% [73/78] vs 93% [75/81]). The presence of histologically demonstrated injured arteries in the submucosal layer with cold snare was significantly less than with conventional snare (22% vs 39%, P = .023).

LIMITATION

Small sample size, single-center study.

CONCLUSIONS

Delayed bleeding requiring hemostasis occurred significantly less commonly after cold snare polypectomy than conventional polypectomy despite continuation of anticoagulants. Cold snare polypectomy is preferred for removal of small colorectal polyps in anticoagulated patients. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT 01553565.).

Cold snare polypectomy vs. Cold forceps polypectomy using double-biopsy technique for removal of diminutive colorectal polyps: a prospective randomized study

OBJECTIVES

There are few data on cold snare polypectomy (CSP) in direct comparison with cold forceps polypectomy (CFP) for colonoscopic resection of diminutive colorectal polyps (DCPs; ≤5 mm). The primary aim of this study was to compare the histologic polyp eradication rate of CSP with that of CFP using double-biopsy technique.

METHODS

This was a randomized controlled trial at a single academic hospital. Of the 165 patients invited, 54 consecutive patients having 117 eligible polyps were enrolled in this study. To evaluate histologic eradication of polyps, two or more additional biopsies were taken from the base and edges of the polypectomy site.

RESULTS

The mean size of polyps was 3.66 mm (±1.13). Most polyps evaluated were tubular adenomas (69.9%). The rate of histologic eradication was significantly higher in the CSP group than in the CFP group (93.2% vs. 75.9%, P=0.009). The time taken for polypectomy was significantly shorter in the CSP group (14.29 vs. 22.03 s, P<0.001). Failure of tissue retrieval was noted in 6.8% of polyps resected by CSP. Multivariate analysis revealed that the method of polypectomy (CFP) and the polyp size (≥4 mm) were independent predictors associated with incomplete histologic eradication (odds ratio (OR) 4.750 (95% confidence interval (CI): 1.459-15.466), OR 4.375 (95% CI: 1.345-14.235); all P<0.05, respectively).

CONCLUSIONS

CSP is superior to CFP for the endoscopic removal of DCPs with regard to completeness of polypectomy. CSP technique should be considered the primary method for endoscopic treatment of polyps in the 4-5-mm size range (ClinicalTrials.gov number: NCT01646242).

Colonoscopic polypectomy: current techniques and controversies

Colonoscopic polypectomy is fundamental to effective colonoscopy. Through its impact on the polyp-cancer sequence, colonoscopic polypectomy reduces colorectal cancer incidence and mortality. Because it eliminates electrosurgical risk, cold snaring has emerged as the preferred technique for most small and all diminutive polyps. Few clinical trial data are available on the effectiveness and safety of specific techniques. Polypectomy technique seems highly variable between endoscopists, with some techniques more effective than others are. Further research is needed to investigate operator variation in polypectomy outcomes and establish an evidence base for best practice.

Colon polypectomy: a review of routine and advanced techniques

The value of performing comprehensive screening colonoscopy with complete colon polypectomy is widely accepted. Colon cancer is a significant cause of worldwide mortality and prospective studies have proven that colonoscopic polypectomy reduces both the incidence and mortality related to this disease. Over the past few decades the array of instruments and techniques have greatly expanded to assist with the safe endoscopic removal of colon polyps. This article will review the published literature regarding efficacy and safety of standard polypectomy techniques such as snare polypectomy, electrocautery, and endoscopic mucosal resection along with newer techniques such as endoscopic submucosal dissection and combined laparoscopic techniques.

A prospective randomized comparison of cold vs hot snare polypectomy in the occurrence of postpolypectomy bleeding in small colonic polyps

AIM

Polypectomy techniques in the removal of polyps in the 3-8 mm size range are inconsistent. The aim of our study was to compare cold (CSP) with hot snare polypectomy (HSP) in the occurrence of postpolypectomy bleeding in small colonic polyps 3-8 mm in size.

METHOD

In all, 414 consecutive patients with small colorectal polyps 3-8 mm in size were prospectively randomized into the CSP group and the HSP group.

RESULTS

There was no early or late postpolypectomy bleeding in either group. Intraprocedural bleeding was significantly more frequent in the CSP group than the HSP group (CSP, 19/208; HSP, 2/206; P<0.001) but resolved spontaneously without any intervention in both groups.

CONCLUSION

The data show that the CSP technique is safe, effective and quicker than HSP for patients and it could be considered the ideal procedure for small polyp removal.

Serrated polyps: critical precursors to colorectal cancer

Colorectal polyps have been traditionally classified as either hyperplastic or adenomatous, with only the latter progressing to carcinoma. However, it is now recognized that certain subtypes of serrated polyps have a risk of malignant transformation via a serrated neoplasia pathway. Serrated polyps are a heterogeneous group of lesions with distinct morphologic, histologic and molecular genetics profiles. Based on available evidence, there are reasons to suspect that this pathway may contribute to interval or missed cancers because serrated lesions are more likely than conventional adenomas to be missed on colonoscopy, and the progression of serrated polyps to cancer may be more rapid. Therefore, it is paramount that physicians recognize the importance of serrated polyps and are aware of the latest surveillance guidelines.

Analysis of delayed postpolypectomy bleeding in a colorectal clinic

PURPOSE

The colonoscopic polypectomy has become a valuable procedure for removing precursors of colorectal cancer, but some complications can be occurred. The most common complication after colonoscopic polypectomy is bleeding, which is reported to range from 1% to 6% and which can be immediate or delayed. Because the management of delayed postpolypectomy bleeding could be difficult, the use of preventive technique and reductions of risk factors are essential.

METHODS

From January 2007 to December 2008, delayed hemorrhage occurred in 18 of the 1,841 polypectomy patients examined by one endoscopist. These cases were reviewed retrospectively for risk factors, pathologic findings, and treatment methods.

RESULTS

Delayed bleeding occurred in 18/1,841 patients (0.95%). The mean age was 55.9 ± 10.9 years, and the male-to-female ratio was 8:1. The most common site was the right colon (11 cases, 61.1%), and the average polyp size was 9.2 ± 2.8 mm. Delayed bleeding was identified from 1 to 5 days after resection (mean, 1.6 ± 1.2 days). The most common macroscopic type of polyp was a sessile polyp (10 cases, 55.6%), and histologic finding was a tubular adenoma in 13 cases (72.2%). Seventeen cases were treated with clipping for hemostasis and 1 case with epinephrine injection.

CONCLUSION

The right colon and a sessile polyp were associated with an increase in delayed postpolypectomy bleeding. Reducing risk factors and close observation were essential in high risk patients, and prompt management with hemoclips was effective.

How Should Patients Requiring Dual Antiplatelet Therapy be Managed When Undergoing Elective Endoscopic Gastrointestinal Procedures?

OPINION STATEMENT

The following are general guidelines for the management of patients on dual antiplatelet therapy as they undergo gastrointestinal procedures with potential for bleeding complications: Avoid cessation of all antiplatelet therapies after percutaneous coronary intervention (PCI) with stent placement when possible. Avoid cessation of clopidogrel (even when aspirin is continued) within the first 30 days after PCI and either drug-eluting stent (DES) or bare metal stent placement. Defer elective endoscopic procedures, possibly up to 12 months, if clinically acceptable from the time of PCI and DES placement. Perform endoscopic procedures, particularly those associated with bleeding risk, 5 to 7 days after thienopyridine drug cessation. Aspirin should be continued when possible. Resume thienopyridine and aspirin drug therapy after the procedure once hemostasis is achieved. A loading dose of the former should be considered among patients at risk for thrombosis. Continue platelet-directed therapy in patients undergoing elective endoscopy procedures associated with a low risk for bleeding.

Colonoscopic polypectomy and associated techniques

Polypectomy of colonic polyps has been shown to reduce the risk of colon cancer development and is considered a fundamental skill for all endoscopists who perform colonoscopy. A variety of polypectomy techniques and devices are available, and their use can vary greatly based on local availability and preferences. In general, cold forceps and cold snare have been the polypectomy methods of choice for smaller polyps, and hot snare has been the method of choice for larger polyps. The use of hot forceps has mostly fallen out of favor. Polypectomy for difficult to remove polyps may require the use of special devices and advanced techniques and has continued to evolve. As a result, the vast majority of polyps today can be removed endoscopically. Since electrocautery is frequently used for polypectomy, endoscopists should be thoroughly familiar with the basic principles of electrosurgery as it pertains to polypectomy. Tattooing of a polypectomy site is an important adjunct to polypectomy and can greatly facilitate future surgery or endoscopic surveillance. The two most common post-polypectomy complications are bleeding and perforation. Their incidence can be decreased with the use of meticulous polypectomy techniques and the application of some prophylactic maneuvers. This review will examine the technique of polypectomy and its complications from the perspective of the practicing gastroenterologist.

Recurrence after endoscopic piecemeal mucosal resection for large sessile colorectal polyps

AIM: To evaluate the safety and outcomes of endoscopic piecemeal mucosal resection (EPMR) for large sessile colorectal polyps.

METHODS: The patients enrolled in this study were 47 patients with 50 large sessile polyps (diameter, 2 cm or greater) who underwent EPMR using a submucosal saline injection technique between December 2002 and October 2005. All medical records, including characteristics of the patients and polyps, complications, and recurrences, were retrospectively reviewed. The first follow-up endoscopic examination was performed at 3-6 mo after initial endoscopic resection, and the second at 12 mo post-EPMR. Subsequent surveillance colonoscopic examinations were individualized, taking risk factors into account.

RESULTS: The patients were 23 men and 24 women, with a mean age of 60 years. Mean polyp size was 30.1 mm. Of 50 polyps identified, 34 (68%) were benign and 16 (32%) were malignant. There were 6 (12%) cases with EPMR-related bleeding: 5 intra-procedural and 1 early post-procedural bleeding. All bleeding episodes were managed by endoscopic clipping or argon beam coagulation. There were no perforations. Recurrence was identified in 5 cases (12.2%): 4 local recurrences detected at 3 mo post-EPMR and 1 local recurrence detected at 14 mo post-EPMR. The recurrence rate after EPMR was 3.1% for benign polyps and 33.3% for malignant polyps (P < 0.05). Median follow-up time was 37 mo.

CONCLUSION: EPMR is safe, but should be applied carefully in malignant polyps. Close follow-up endoscopic examinations are necessary for early detection of recurrence.

Cap-assisted endoscopic mucosal resection for colorectal polyps

PURPOSE

Cap-assisted endoscopic mucosal resection has been used to treat superficial esophageal and gastric cancers. Efficacy data in the colon are limited. The aim of the study was to evaluate the safety and efficacy of this technique in the treatment of sessile polyps and lateral spreading tumors in the colorectum.

METHODS

Two-hundred and fifty-five consecutive patients with sessile polyps or lateral spreading tumors >or=20 mm were treated between January 2000 and December 2007.

RESULTS

A total of 146 sessile polyps and 136 lateral spreading tumors were treated with cap-assisted endoscopic mucosal resection. Complications occurred in 22 (8.6%) patients (5.5% in sessile polyps and 10.3% in lateral spreading tumors). Intraprocedural bleeding occurred in 21 (7%) of polypectomies (6% in sessile polyps and 10% in lateral spreading tumors); all were controlled endoscopically. Postcoagulation syndrome occurred in 1 patient with lateral spreading tumor. No perforation occurred. Invasive adenocarcinoma was found in 35 patients, of whom 15 underwent surgery. Endoscopic follow-up in 200 patients with 216 adenomas for a median of 12.1 months showed recurrence in 8 (4%) who were treated with resection and/or ablation.

CONCLUSIONS

Cap-assisted endoscopic mucosal resection is an effective treatment for sessile polyps and lateral spreading tumors. A disadvantage of the technique is that the resection is piecemeal. Close surveillance provides the opportunity for additional tissue ablation, when required, to achieve complete lesion removal.

Endoscopic Polypectomy Using Endocautery in Three Dogs and One Cat

Endoscopic polypectomy has long been employed in humans with either gastric or colonic polyps. Despite the frequency of use in humans, reports in veterinary medicine remain scarce. The medical records of three dogs and one cat were reviewed. Two animals that were presented with hematochezia underwent colonoscopic polypectomy and were clinically normal 22 months and 6 months postpolypectomy. One animal that was presented with chronic vomiting underwent gastric polypectomy and was clinically normal 21 months postpolypectomy. One animal with an incidentally discovered gastric polyp underwent polypectomy without complication. Endoscopic polypectomy may be a viable alternative to surgery in veterinary patients with gastric or colonic polyps.