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

Endoscopic resection of local recurrences of diminutive polyps by cold forceps polypectomy

OBJECTIVES

Cold forceps polypectomy (CFP) is an effective treatment for diminutive colorectal polyps. However, polyps occasionally recur, and there is no consensus on their long-term clinical management. Therefore, we investigated the short- and long-term clinical outcomes of re-CFP for recurrent diminutive colorectal polyps.

MATERIALS AND METHODS

This was a follow-up of a multicenter, prospective study investigating the clinical outcomes of diminutive colorectal polyps excised by CFP with narrowband imaging-enhanced endoscopy and jumbo forceps. We evaluated short-term outcomes of re-CFP and patients at 1-year follow-up post re-CFP for recurrent colorectal polyps to determine long-term recurrence rates. Additionally, complete resection rates, clinicopathological features, number of forceps bites, and rate of short-term adverse events managed by re-CFP were evaluated.

RESULTS

At 1-year follow-up, local recurrence was identified in 18 patients from the original study. The mean size of local recurrent polyps was 1.5 ± 0.6 mm, and all recurrent lesions were < 3 mm. Re-CFP could successfully excise locally recurrent polyps in all cases. All recurrent lesions were low-grade adenomas; no adverse events were reported. Additionally, 16 of 18 patients were evaluated endoscopically at 2-year follow-up; no recurrence was observed.

CONCLUSIONS

Recurrent lesions following initial CFP were small and pathologically benign, and re-CFP was an effective treatment.

Is Submucosal Injection Helpful in Cold Snare Polypectomy for Small Colorectal Polyps?

BACKGROUND/AIMS

Cold snare polypectomy (CSP) is an effective method of polyp removal for small colorectal polyps. However, the effect of submucosal injection in cold snare endoscopic mucosal resection (CS-EMR) for small polyps is unclear. Therefore, this study aimed to evaluate the effect of submucosal injection in CS-EMR for small polyps.

METHODS

Between 2018 and 2019, 100 consecutive small colorectal polyps (5-10 mm) were identified in 58 patients. The first 50 consecutive polyps were removed by CS-EMR, and the remaining 50 were removed by CSP. Demographic data, clinical data, endoscopic findings, procedure times, complication rates, and pathology data were collected.

RESULTS

No difference in the complete resection rate was observed between the CS-EMR and CSP groups. A total of 9 polyps showed post-polypectomy bleeding (7 had immediate bleeding, 1 had delayed bleeding, and 1 had both immediate and delayed bleeding). No difference in the bleeding rate was observed between the two groups. In multivariate analysis, warfarin (odds ratio [OR], 42.334; 95% confidence interval [CI], 1.006-1,781.758) and direct-acting oral anticoagulants (OR, 35.244; 95% CI, 3.853-322.397) showed a significantly increased risk of bleeding.

CONCLUSION

The effect of submucosal injection in CSP was not significant for small colorectal polyps.

Is jumbo biopsy forceps comparable to cold snare for diminutive colorectal polyps? - a meta-analysis

Background and study aims  Diminutive colorectal polyps are increasingly being detected and it is not clear whether jumbo biopsy forceps (JBF) has comparable efficacy to that of cold snare polypectomy (CSP) for management of these lesions. Methods  An electronic literature search was performed for studies comparing resection rates of JBF and CSP for diminutive polyps (≤ 5 mm). The primary outcome was incomplete resection rate (IRR). Secondary outcomes included failure of tissue retrieval and complication rates (post-polypectomy bleeding, perforation etc.). Leave-one-out analysis was performed to examine the disproportionate role of any of the studies. Meta-analysis outcomes and heterogeneity (I ² ) were computed using Comprehensive meta-analysis software. Results  A total of 4 studies (3 randomized controlled trials and 1 retrospective study) with 407 patients and 569 total polyps (mean size of 3.62 mm) was included for analysis. IRR of JBF was slightly higher than that of CSP (10.2 % vs 7.2 %) but this was not statistically significantly different (Pooled OR 1.76; 95 % CI 0.94-3.28; I ²  = 0 ). Leave-one-out analysis showed no significant difference in the pooled OR comparison either. Two of the 4 studies reported 0 % failure of tissue retrieval for JBF and 1 % and 4.3 % for CSP. There were no complications for either group from the 2 studies that reported this outcome. The quality of the included studies was moderate to high. Conclusions  This systematic review with only limited data shows that JBF and CSP are not statistically different in completely removing diminutive polyps, although careful endoscopic assessment is needed to ensure complete removal of all polyp tissue.

Personalizing Polypectomy Techniques Based on Polyp Characteristics

Polypectomy is an essential skill for all endoscopists performing lower gastrointestinal endoscopy. Different polypectomy tools and techniques have evolved and it is important that endoscopists are familiar with these so they can select the most appropriate technique for each polyp. This narrative review updates the different concepts in tailoring polypectomy technique to the characteristics of polyps. Effective polypectomy requires different components, including the following: careful evaluation of the polyp; decision making about optimal polyp management; actual polypectomy, which includes careful positioning of the endoscope and polyp; and postpolypectomy evaluation of the results (for completeness of resection and prophylaxis of complications).

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.

Dedicated Cold Snare vs. Traditional Snare for Polypectomy of Diminutive and Small Lesions in a Porcine Model: A Research Group for Endoscopic Instruments and Stents (REIS) Study

BACKGROUND/AIMS

The aim of this in vivo animal study was to evaluate the effectiveness and safety of dedicated cold snare (DCS) compared with those of traditional snare (TS) for cold snare polypectomy (CSP).

METHODS

A total of 36 diminutive (5 mm) and 36 small (9 mm) pseudolesions were made by electrocoagulation in the colons of mini-pigs.

RESULTS

For the diminutive lesions, there were no significant differences in technical success rate, procedure time, or complete resection rate between the DCS and TS groups; the rate of uneven resection margin in the DCS group was significantly lower than that of the TS group. For small lesions, technical success rate and complete resection rate were significantly higher in the DCS group than in the TS group (100% [18/18] vs. 55.6% [10/18], p=0.003; 94.4% [17/18] vs. 40% [4/10], p=0.006). In addition, the procedure duration was significantly shorter, and the rate of uneven resection margin was significantly lower in the DCS group (28.5 sec vs. 66.0 sec, p=0.006; 11.1% [2/18] vs. 100% [10/10], p<0.001). Two cases of perforation occurred in the DCS group. Multivariate analysis revealed that DCS use was independently associated with complete resection.

CONCLUSION

DCS is superior to TS in terms of technical success, complete resection, and reducing the duration of the procedure for CSP of small polyps.

Rates of Incomplete Resection of 1- to 20-mm Colorectal Polyps: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Incomplete resection of neoplastic colorectal polyps can result in postcolonoscopy colorectal cancer. We performed a systematic review and meta-analysis to determine the incomplete resection rate (IRR) of colorectal polyps and associated factors.

METHODS

We searched MEDLINE, EMBASE, EBM Reviews, and CINAHL to identify full-text articles that reported IRRs of polyps 1 to 20 mm, published until March 2019. Exclusion criteria were studies of inflammatory bowel disease cohorts, referrals for difficult polypectomy, polyp sizes larger than 20 mm, and endoscopic submucosal resection and/or dissection as polypectomy approaches. IRRs were calculated based on findings from biopsies taken at polypectomy sites or assessments of margins of resected polyps. The primary outcome was IRR for snare removal of polyps 1 to 20 mm. Secondary outcomes included IRR for polyps 1 to 10 mm and 10 to 20 mm, IRR for hot and cold snare removal of polyps 1 to 10 mm and 10 to 20 mm, IRR of snare removal with or without submucosal injection, and IRR for forceps and cold snare removal of polyps 1 to 5 mm.

RESULTS

We identified 6148 reports and used 32 studies, with a total of 9282 polyps, in our quantitative analysis. The IRR for snare removal of polyps 1 to 20 mm was 13.8% (95% confidence interval [CI] 10.3-17.3; 13 studies, 5128 polypectomies). IRRs were 15.9% for snare removal of polyps 1 to 10 mm (95% CI 9.6-22.1; 9 studies, 2531 polypectomies) and 20.8% for snare removal of polyps 10 to 20 mm (95% CI 12.9-28.8; 6 studies, 412 polypectomies). The IRR for hot snare removal of polyps 1 to 10 mm was 14.2% (95% CI 5.2-23.2) vs 17.3% for cold snare polypectomy (95% CI 14.3‒20.3). The IRR for forceps removal of polyps 1 to 5 mm was 9.9% (95% CI 7.1-13.0) vs 4.4% for snare polypectomy (95% CI 2.9-6.1).

CONCLUSIONS

In a systematic review and meta-analysis, we found that colorectal polyps 1 to 20 mm are frequently incompletely resected, and that risk increases for polyps 10 mm or larger. There is no difference in IRRs of cold vs hot snares for polyps 1 to 10 mm. Snare polypectomy should be used over forceps for polyps 1 to 5 mm.

Optimal Endoscopic Treatment and Surveillance of Serrated Polyps

Serrated polyps are considered precursor lesions that account for 15% to 30% of colorectal cancers, and they are overrepresented as a cause of interval cancers. They are difficult to detect and resect comprehensively; however, recent data suggest that high definition endoscopy, chromoendoscopy (via spray catheter, pump or orally), narrow band imaging, split-dose bowel preparation and a slower withdrawal (>6 minutes) can all improve detection. Cold snare resection is effective and safe for these lesions, including cold snare piecemeal endoscopic mucosal resection, which is likely to become the standard of care for lesions >10 mm in size. Sessile serrated lesions ≥10 mm in size, those exhbiting dysplasia, or traditional serrated adenomas increase the chance of future advanced neoplasia. Thus, a consensus is emerging: a surveillance examination at 3 years should be recommended if these lesions are detected. Serrated lesions likely carry equivalent risk to adenomas, so future guidelines may consider serrated class lesions and adenomas together for risk stratification. Patients with serrated polyposis syndrome should undergo surveillance every 1 to 2 years once the colon is cleared of larger lesions, and their first degree relatives should undergo screening every 5 years starting at age 40.

Indications for Cold Polypectomy Stratified by the Colorectal Polyp Size: A Systematic Review and Meta-Analysis

Objectives:

Cold polypectomy (CP) is widely used because of its safety profile. This systematic review and meta-analysis aimed to clarify the indications for CP based on polyp size.

Methods:

We searched PubMed and the Cochrane Library for randomized controlled trials that compared cold snare polypectomy (CSP) and other procedures for polyps ≤10 mm. Large-scale prospective observational studies were also searched to assess delayed bleeding rates. The studies were integrated to assess the risk ratio for incomplete resection rates according to polyp size. The Cochrane risk of bias tool was used to evaluate the study bias. The certainty of cumulative evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation system.

Results:

We found 280 articles and reviewed their eligibility. We selected and extracted 12 randomized controlled trials and 3 prospective observational studies. The risk ratio of incomplete resection of polyps ≤10 mm using CSP compared with hot snare polypectomy (HSP) was 1.36 (95% confidence interval [CI], 0.92-2.01). The risk ratio for incomplete removal using CSP compared with cold forceps polypectomy (CFP) was 0.50 (95% CI, 0.31-0.82). For polyps ≤3 mm, the risk ratio of CSP compared with CFP was 1.40 (95% CI, 0.39-4.95). Certainty of cumulative evidence was considered low. No delayed bleeding after CP was reported after the treatment of 3446 polyps.

Conclusions:

CSP and HSP may result in the same complete resection rates for polyps ≤10 mm. For polyps ≤3 mm, CFP and CSP may have the same resection rates (PROSPERO registration number: CRD42019122132).

Underwater versus conventional endoscopic resection of nondiminutive nonpedunculated colorectal lesions: a prospective randomized controlled trial (with video)

BACKGROUND AND AIMS

Incomplete resection of colorectal neoplasia decreases the efficacy of colonoscopy. Conventional resection (CR) of polyps, performed in a gas-distended colon, is the current standard, but incomplete resection rates of approximately 2% to 30% for nondiminutive (>5 mm), nonpedunculated lesions are reported. Underwater resection (UR) is a novel technique. The aim of this study was to determine the incomplete resection rates of colorectal lesions removed by UR versus CR.

METHODS

In a randomized controlled trial, patients with small (6-9 mm) and large (≥10 mm) nonpedunculated lesions were assigned to CR (gas-distended lumen) or UR (water-filled, gas-excluded lumen). Small lesions in both arms were removed with a dedicated cold snare. For CR, large lesions were removed with a hot snare after submucosal injection. For UR, large lesions were removed with a hot snare without submucosal injection. Four-quadrant biopsy samples around the resection sites were used to evaluate for incomplete resection.

RESULTS

Four hundred sixty-two eligible polyps (248 UR vs 214 CR) from 255 patients were removed. Incomplete resection rates for UR and CR were low and did not differ (2% vs 1.9%, P = .91). UR was performed significantly faster for lesions ≥10 mm in size (10-19 mm, 2.9 minutes vs 5.6 minutes, P < .0001); ≥20 mm, 7.3 minutes vs 9.5 minutes, P = .015).

CONCLUSIONS

Low incomplete resection rates are achievable with UR and CR. UR is effective and safe with the advantage of faster resection and potential cost savings for removal of larger (≥10 mm) lesions by avoiding submucosal injection. As an added approach, UR has potential to improve the cost-effectiveness of colonoscopy by increasing efficiency and reducing cost while maintaining quality. (Clinical trial registration number: NCT02889679.).

Discrepancy between self-reported and actual colonoscopy polypectomy practices for the removal of small polyps

BACKGROUND AND AIMS

Cold snare polypectomy (CSP) is associated with higher rates of complete resection compared with cold biopsy forceps (CBF) for the removal of small polyps (4-9 mm). This study aimed to evaluate self-reported polypectomy preferences and actual practice patterns among endoscopists at an academic center and to identify factors associated with the use of CSP for small polyps.

METHODS

In phase A, endoscopists completed a survey evaluating preferences for polypectomy techniques. In phase B, we performed a retrospective analysis of all consecutive colonoscopies with polypectomy (January 2016 to September 2018). Uni- and multivariate analysis were performed to identify factors associated with CSP for small polyps.

RESULTS

Nineteen of 26 (73%) endoscopists completed the survey (phase A); 3 (15.8%) were interventional endoscopists. Most respondents indicated that they use CSP (89.5%) for small polyps and identified no reasons for choosing CBF over CSP (73.7%). In phase B, we identified 1118 colonoscopies with 2625 polypectomies for polyps ≤9 mm. Most diminutive polyps (≤3 mm) were removed with CBF (819 of 912; 90%). CBF (46.2%) was also preferentially used for removal of small polyps (n = 1713), followed by hot snare polypectomy (27.2%), and CSP (26.6%). On multivariate analysis, interventional endoscopists were associated with a higher likelihood of using CSP for small polyps (odds ratio, 1.38; 95% confidence interval, 1.07-1.79; P = .01).

CONCLUSIONS

Significant discrepancy exists between self-reported preferences and actual polypectomy practices. CBF is still preferentially used over CSP for the removal of polyps sized 4-9 mm; further strategies are needed to monitor and implement adequate polypectomy techniques.

Clinical implications of decision making in colorectal polypectomy: an international survey of Western endoscopists suggests priorities for change

Introduction  Colonoscopy prevents colorectal cancer via the detection and resection of premalignant polyps. This effect may be attenuated by variations in polypectomy, with multiple techniques available and a wide range of experience amongst endoscopists. We assessed current practice against the best available contemporary evidence. Methods  An online survey was distributed to members of the gastroenterological and surgical societies of seven countries during July 2017. Images of colorectal polyps were presented and respondents requested to provide the polypectomy technique they would employ in their daily practice. Responses were compared to the evidence-based techniques in the 2017 ESGE Colorectal Polypectomy Guideline. Results  In total, 707 endoscopists (627 physicians, 71 surgeons, 9 nurse endoscopists, median practice duration 18 years) completed the survey. Of these, 3.1 % selected hot biopsy forceps and 5.2 % hot snare polypectomy (without submucosal lifting) to remove a 3 mm ascending colon polyp. Only 43.3 % selected cold snare polypectomy (CSP) to remove an 8 mm ascending colon polyp. Surgical referral was selected by 16.7 % of respondents for a 45 mm transverse colon polyp without endoscopic evidence of submucosal invasive cancer (SMIC). Endoscopic resection was selected by 12.0 % for an 80 mm sigmoid polyp with imaging consistent with deep SMIC, and a further 26.4 % selected tertiary endoscopist referral, suggesting they had not appreciated that it was endoscopically unresectable. Conclusion  CSP is underutilized for small polyp resection despite its favorable safety and efficacy. Benign polyps are commonly referred for surgery and overt SMIC is underappreciated using endoscopic imaging. Addressing these issues may reduce diathermy-related adverse events, surgery, and unnecessary colonoscopic procedures for patients and reduce rates of post-colonoscopy colorectal cancer.

Present Status of Endoscopic Submucosal Dissection for Non-Ampullary Duodenal Epithelial Tumors

Prediction of histology by endoscopic examination is important in the clinical management of non-ampullary duodenal epithelial tumors (NADETs), including adenoma and adenocarcinoma. The use of a simple scoring system based on the findings of white-light endoscopy or magnified endoscopy with narrow-band imaging is useful to differentiate between Vienna category 3 (C3) and C4/5 lesions. Less invasive endoscopic resection procedures, such as cold snare polypectomy, are quick to perform and convenient for small (<10 mm) C3 lesions. Neoplasms with higher grade histology, such as C4/5 lesions, should be treated by endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), or surgery. Although EMR often requires piecemeal resection, the complication rate is acceptable. Excellent complete resection rates could be achieved by ESD; however, it remains a challenging method considering the high risk of complications. Shielding or closure of the ulcer after ESD is effective at decreasing the risk of delayed bleeding and perforation. Laparoscopic endoscopic cooperative surgery is an ideal treatment with a high rate of en bloc resection and a low rate of complications, although it is limited to high-volume centers. Patients with NADETs could benefit from a multidisciplinary approach to stratify the optimal treatment based on endoscopic diagnoses.

Dye-based chromoendoscopy following polypectomy reduces incomplete polyp resection

Background and study aims  The completeness of a polyp resection is an important determinant of quality in colonoscopy, and may reduce incidence of interval cancers. Incomplete resection rates (IRR) vary widely and range from 6.5 % to 22.7 %. Residual disease is more likely with larger polyps, for sessile serrated adenomas, and with more proximal lesions. Chromoendoscopy is increasingly employed in lesion detection. The aims of this study were to assess local IRR, and to determine whether chromoendoscopy could correctly identify residual disease post polypectomy. Patients and methods  This was a prospective study examining post polypectomy sites. Chromoendoscopy (0.13 % indigo carmine) was applied to resection bases to identify residual disease. Targeted base biopsies were taken from identified residual disease (positive group) or random base biopsies were taken when a clear base was visualised (negative group). Overall rates of incomplete resection were documented. Reported rates post chromoendoscopy and actual histological rates were documented and compared. Results  A total of 102 polyps were identified for inclusion, of which 15 % (n = 16) were excluded. Resection quality was evaluated in 86 polyps of 61 patients (female n = 33 54 %; mean Age 62.3 years). Polyps were mainly removed by cold snare (n = 71, 82.5 %). Most polyps (n = 58, 67 %) measured between 5 to 10 mm. Polyps were largely located in the right colon (n = 57, 66 %). Overall histological residual disease occurred in 17 /86 (19.6 %). Chromoendoscopy correctly identified residual disease in 13 of 17 bases (76.5 %). Only four of /86 (4.6 %) of polyp bases were missclassified post-chromoendoscopy (odds ratio 0.284 (95 % CI 0.0857-0.9409), P  = 0.03). Conclusion  Indigo carmine chromoendoscopy improves early detection of residual disease post polypectomy, reducing incomplete resection rates.

Usefulness of cold polypectomy under linked color imaging

Background and study aims  Cold polypectomy is becoming popular for treatment of colon polyps due to its safety and convenience, but there is still the problem of tumor remnants. Because linked color imaging (LCI) improves polyp visibility, cold polypectomy under LCI is anticipated to reduce the tumor remnant rate. Therefore, we investigated the usefulness of this procedure. Patients and methods  Fifty patients scheduled to undergo cold polypectomy for treatment of colon polyps < 10 mm and assumed to be adenomas were registered prospectively. After performing cold snare polypectomy (CSP) under LCI, biopsy was performed at two resection margin sites for each polyp to determine the tumor remnant rate. Results  A total of 145 lesions were treated by CSP. Of the 139 lesions in which polyps were retrievable and diagnosed as adenomas pathologically, one lesion was recognized as a remnant adenoma on biopsy (remnant rate: 0.7 % [95 % CI: 0.0-4.4]). This remnant rate was extremely low. Treatment results were extremely promising given that en bloc resection, post-procedure bleeding, and perforation rates were 100 %, 0 %, and 0 %, respectively. Conclusion  Cold snare polypectomy under LCI may be an effective treatment method capable of reducing the tumor remnant rate. This trial was approved by our Institutional Ethics Committee and registered at the University Hospital Medical Information Network (UMIN 000033690).

Underwater cold snare polypectomy for colorectal adenomas

BACKGROUND AND AIM

Cold snare polypectomy (CSP) is a safe treatment for colorectal adenomas. However, the R0 resection rate is not sufficiently high because of inadequate resection of muscularis mucosa. We hypothesized that CSP in an underwater environment could improve this procedure by helping to safely achieve resection containing the muscularis mucosa. We have named this procedure underwater cold snare polypectomy (UCSP). We aimed to investigate the efficacy and safety of UCSP for colorectal adenomas.

METHODS

Between May 2017 and April 2018, patients diagnosed with colorectal adenomas <9 mm underwent UCSP. After follow-up colonoscopy 3 weeks later, the patients post-UCSP scars were biopsied. Outcomes were compared with those of a historical control group who underwent conventional CSP in our previous study using propensity score-matching methods.

RESULTS

Overall, 224 lesions in 65 patients were prospectively resected by UCSP. Pathologically, 209 lesions were adenomas (4.5 ± 1.5 mm) including one intramucosal carcinoma. Only one pathological residual adenoma was identified, but there was no significant difference in the residual rate between the UCSP and CSP groups (both 1.0%). No complications were observed. R0 resection rate and rate of area containing the muscularis mucosa in the UCSP group were significantly higher than those in the CSP group (80.2% vs 32.7%, P < 0.001; 50.0% vs 35.3%, P = 0.015).

CONCLUSION

Underwater cold snare polypectomy for diminutive and small colorectal adenomas was safe and effective from the perspective of pathological complete resection, which is likely facilitated by achieving an adequate depth of resection.

Comparison of Outcomes of Colorectal Polypectomy Using Traditional Snare and Rotary Snare: A Prospective Randomized Controlled Trial

Background and Objective

The aim of the current study was to compare the efficacy and safety of polypectomy by using rotary snare vs. traditional snare during colonoscopy.

Methods

A single-center randomized controlled trial, which included consecutive participants who were ≥18 years old and detected with polyp(s) during routine colonoscopy between July and September 2018, was conducted. Participants with colorectal polyps were randomized to receive polypectomy using rotary snares or traditional snares. The primary outcome measure was the comparison of the average time of removing a polyp between those two groups. The secondary outcome measure was to compare the polyp resection time by using SMSA (size, morphology, site, and access) scores.

Results

A total of two hundred participants were included in this study. Of them, 100 participants were randomly assigned to the rotary snare group (214 polyps) and the other 100 participants were randomly assigned to the traditional group (232 polyps). The mean resection time was significantly shorter in the rotary snare group than in the traditional snare group (24.41 ± 18.14 seconds vs. 29.53 ± 25.74 seconds, P = 0.021). In the subgroup analysis, the resection time was also shorter in the rotary snare group than in the traditional snare group in SMSA level 1 (18.51 ± 8.26 seconds vs.23.84 ± 15.07 seconds, P = 0.013) and in SMSA level 2 (25.03 ± 15.32 seconds vs.29.15 ± 24.82 seconds, P = 0.009), respectively.

Conclusion

Colorectal polyps could be removed more efficient by using rotary snares than by using traditional snares in SMSA level 1 and SMSA level 2.

Metachronous Neoplasias Arise in a Higher Proportion of Colon Segments From Which Large Polyps Were Previously Removed, and Can be Used to Estimate Incomplete Resection of 10-20 mm Colorectal Polyps

BACKGROUND & AIMS

Incomplete resection of polyps could be an important cause of post-colonoscopy colorectal cancer. However, it is difficult to study progression of incompletely removed polyps or their clinical importance. We aimed to estimate incomplete polyp resection using risk of metachronous neoplasia per colon segment.

METHODS

We performed a retrospective study of 1031 patients (6186 colon segments) who initially underwent resection of a large (10-20 mm) neoplastic polyp at 2 academic medical centers (from 2000 through 2012) and then underwent a subsequent colonoscopy within 0.5 to 5 years. We determined the proportions of metachronous neoplasia in colon segments from which a single large neoplastic polyp was removed and in segments without prior neoplasia. We then used the absolute difference in proportions between these groups to estimate the rate of incomplete resection. Our analysis assumed that development of metachronous neoplasia in each colon segment was the consequence of a newly grown polyp, a previously missed polyp, or an incompletely removed polyp.

RESULTS

Metachronous neoplasia was detected in 177 of 757 segments (23.4%) with a single large polyp, and in 438 of 4232 segments (10.3%) without any neoplasia at baseline colonoscopy (P < .001). Resections were therefore estimated to be incomplete in 13.0% of segments (95% CI, 9.8-16.2). This proportion was greater for sections with non-pedunculated polyps (18.3%; 95% CI, 14.2-22.5) than pedunculated polyps (3.5%; 95% CI, -0.7 to -11.3; P < .001). A higher proportion of piecemeal resections appeared to be incomplete (28.0%; 95% CI, 20.2-35.7) than of en bloc resections (9.2%; 95% CI, 5.9-12.5) (P < .001). No differences in incomplete resection were associated with polyp histology.

CONCLUSION

Metachronous neoplasia arises in a significantly higher proportion of colon segments from which a polyp was previously removed. Based on these data, we estimate that 13% of all large polyps are incompletely resected and 18% of large non-pedunculated polyps are incompletely resected. These findings indicate that incomplete resection could be a risk factor for later development of neoplasia. Segment metachronous neoplasia might be used as a marker of resection quality.

The Cold Revolution: How Far Can It Go?

Cold resection for small colonic polyps, and larger lesions, is being rapidly and widely adopted. Driven by an impressive safety and cost profile compared with conventional polypectomy, these advantages are offset by the limitations of smaller and shallower resection, and absent thermal effects that may permit persistence of residual neoplasia. To overcome this, optimal cold snare technique requires inclusion of a margin of normal mucosa and a piecemeal resection technique for larger polyps. This article examines the fundamentals of cold snare resection and evidence for its application, theorizes on limits to its application, and identifies areas for further research.

A simplified table using validated diagnostic criteria is effective to improve characterization of colorectal polyps: the CONECCT teaching program

Introduction and study aims  Accurate real-time endoscopic characterization of colorectal polyps is key to choosing the most appropriate treatment. Mastering the currently available classifications is challenging. We used validated criteria for these classifications to create a single table, named CONECCT, and evaluated the impact of a teaching program based on this tool. Methods  A prospective multicenter study involving GI fellows and attending physicians was conducted. During the first session, each trainee completed a pretest consisting in histological prediction and choice of treatment of 20 colorectal polyps still frames. This was followed by a 30-minute course on the CONECCT table, before taking a post-test using the same still frames reshuffled. During a second session at 3 - 6 months, a last test (T3 M) was performed, including these same still frames and 20 new ones. Results  A total 419 participants followed the teaching program between April 2017 and April 2018. The mean proportion of correctly predicted/treated lesions improved significantly from pretest to post-test and to T3 M, from 51.0 % to 74.0 % and to 66.6 % respectively ( P  < 0.001). Between pretest and post-test, 343 (86.6 %) trainees improved, and 153 (75.4 %) at T3 M. Significant improvement occurred for each subtype of polyp for fellows and attending physicians. Between the two sessions, trainees continued to progress in the histology prediction and treatment choice of polyps CONECCT IIA. Over-treatment decreased significantly from 30.1 % to 15.5 % at post-test and to 18.5 % at T3 M ( P  < 0.001). Conclusion  The CONECCT teaching program is effective to improve the histology prediction and the treatment choice by gastroenterologists, for each subtype of colorectal polyp.

Best Practices for Resection of Diminutive and Small Polyps in the Colorectum

Diminutive colorectal lesions are polyps and flat lesions 1 to 5 mm in size, and small are 6 to 9 mm in size. The best resection method is the cold snare. Cold forceps are acceptable for 1- to 3-mm lesions, but should not be used to piecemeal polyps. Cold snaring has few complications and is more effective than cold forceps for 4- to 5-mm polyps and as effective and more efficient than hot snaring for 6- to 9-mm polyps.

Clinicopathological features, diagnosis, and treatment of sessile serrated adenoma/polyp with dysplasia/carcinoma

Sessile serrated adenoma/polyps (SSA/Ps) are early precursor lesions in the serrated neoplasia pathway, which results in BRAF-mutated colorectal carcinomas with not only high levels of microsatellite instability but also microsatellite stable. SSA/Ps with advanced histology, including cytological dysplasia or minimally invasive carcinomas, are important lesions because SSA/Ps are considered major contributors to "interval cancers" and these lesions can rapidly become dysplastic or invasive carcinomas. Clinicopathologically, SSA/Ps with dysplasia or invasive carcinoma were associated with advanced age, female sex, and proximal colon. Although SSA/Ps with submucosal invasive carcinoma were smaller and invaded less deeply into the submucosal layer than conventional tubular adenomas with submucosal invasive carcinoma, SSA/Ps with submucosal invasive carcinoma frequently had a mucinous component and exhibited a higher potential for lymphatic invasion and lymph node metastasis. In an SSA/P series, endoscopic characteristics, including (semi)pedunculated morphology, double elevation, central depression, and reddishness, may help accurately diagnose SSA/Ps with advanced histology. Removal of SSA/Ps with dysplasia or invasive carcinoma was recommended. Endoscopic treatment such as endoscopic mucosal resection or endoscopic submucosal dissection is useful for those lesions. However, surgical resection with lymph node dissection might be indicated when SSA/Ps with invasive carcinoma are endoscopically suspected, because these have the high risk of lymph node metastasis. Greater awareness may promote further research into improving the detection, recognition, and complete resection rates of SSA/Ps with dysplasia or invasive carcinoma and reduce the interval cancer rates.

Assessing the Quality of Polypectomy and Teaching Polypectomy

Ineffective polypectomy technique may lead to incomplete polyp resection, high complication rates, interval colorectal cancer, and costly referral to surgery. Despite its central importance to endoscopy, training in polypectomy is not standardized nor has the most effective training approach been defined. Polypectomy competence is rarely reported and quality metrics for this skill are lacking. Use of tools and measurements to assess polypectomy outcomes is low. There is a need for standardization of training and remediation in polypectomy; defining standards of competent polypectomy and how it is feasibly measured; and integration of polypectomy quality metrics into training programs and the accreditation process.

Underwater polypectomy without submucosal injection for colorectal lesions ≤ 20 mm in size-a multicenter retrospective observational study

BACKGROUND

Underwater polypectomy (UWP) of large (≥ 20 mm) colorectal lesions is well described, but reports of UWP for lesions ≤ 20 mm in size, which account for > 95% of polyps encountered in routine clinical practice, are limited. We assessed the feasibility of UWP in routine practice across various sites for colorectal lesions ≤ 20 mm in size.

METHODS

A multicenter retrospective study was performed on pooled data from nine colonoscopists at 3 U.S., 1 Taiwanese and 2 Italian sites. Outcomes related to UWP on lesions ≤ 20 mm in size were analyzed.

RESULTS

In 117 patients, UWP netted 169 lesions. Polypectomy by hot (HSP, 54%) or cold (CSP, 41%) snare, and cold forceps (CFP, 5%) were performed successfully without endoscopic evidence of residual neoplasia or immediate clinically significant adverse events. The majority (74.6%) were tubular adenomas; 60.9% were from the proximal colon. Histopathologic margins were positive in 4 and unavailable in 26 CSP and 24 HSP specimens. The remainder had negative resection margins on pathologic reports.

CONCLUSION

UWP for colorectal lesions ≤ 20 mm in routine practice across multiple sites confirms the feasibility and acceptability of this technique. Improvement of resection outcomes by UWP in routine practice deserves further evaluation in a randomized controlled trial.

Colon polypectomy report card improves polypectomy competency: results of a prospective quality improvement study (with video)

BACKGROUND AND AIMS

Polypectomy competency varies significantly among providers. Poor polypectomy technique may lead to interval cancer and/or adverse events. Our aim was to determine the effect of a polypectomy skills report card on subsequent polypectomy performance.

METHODS

We conducted a 3-phase, prospective, single-blinded study. In phase 1 ("baseline"), we graded 10 polypectomies per endoscopist using the Direct Observation of Polypectomy Skills (DOPyS) tool (scores 1-4); mean overall scores ≥3 are competent. In phase 2 ("pre-report card"), we selected 10 additional polypectomies per endoscopist. We subsequently gave endoscopists a report card with baseline scores and instructional videos demonstrating optimal polypectomy technique. In phase 3 ("post-report card"), 10 additional polypectomies per endoscopist were selected. Raters, blinded to study phase, graded 10 pre- and 10 post-report card polypectomies per endoscopist. We compared mean DOPyS scores and rate of competent polypectomy in the pre- and post-report card phases.

RESULTS

We graded 110 pre- and 110 post-report card polypectomies performed by 11 endoscopists. The mean DOPyS score increased between the pre- and post-report card phases (2.7 ± .9 vs 3.0 ± .8, P = .01); this improvement was seen for diminutive (P < .0001) but not for small-to-large polyps. Rate of competent polypectomy significantly improved from the pre- to post-report card phase (56% vs 69%, P = .04); this improvement was seen for diminutive (57% vs 81%, P = .001) but not for small-to-large polyps (55% vs 36%, P = .2).

CONCLUSIONS

Report cards with educational videos effectively improved polypectomy technique, primarily because of improvements in resecting diminutive polyps. The improved competency and decreased piecemeal resection may reduce the risk of polyp recurrence. Further education is needed to improve larger polyp resection.

Risk of metachronous advanced lesions after resection of diminutive and small, non-advanced adenomas

BACKGROUND AND AIMS

Current post-polypectomy surveillance interval guidelines do not discriminate between 1-2 diminutive (1-5mm) and small (6-9mm) non-advanced adenomas. This study compared the risk for metachronous advanced lesions in these groups.

METHODS

Patients with 1-2 diminutive, non-advanced adenomas and no further advanced lesions, and patients with no polyps at baseline colonoscopy were retrospectively analyzed to determine the rate of metachronous advanced lesions. These were defined as the combined rate of colon cancer, advanced adenoma and ≥ 3 non-advanced adenomas at surveillance colonoscopy. Polyp size was measured either subjectively by the endoscopist or by pathology-based measurements.

RESULTS

Among patients with diminutive (n = 395) and small polyps (n = 110), advanced lesions were found in 68 patients (17.2%) and 16 patients (14.5%), respectively (P = 0.53), during a mean follow-up of 4.3 ± 0.9 years. In contrast, advanced lesions were observed in 33 patients (6.6%) in the no polyp group (n = 505), significantly lower than diminutive (P = 0.000) and small polyp groups (P = 0.002), despite a mean follow-up duration of 6.1 ± 1.9 years. The rate of metachronous advanced lesions was also similar between patients with 1-3mm polyps (16%) versus 7-9mm polyps (15.8%).

CONCLUSIONS

Our findings suggest that among patients who underwent polypectomy of up to 2 non-advanced adenomas, those with diminutive and small polyps have the same risk of metachronous advanced lesions; thus, supporting uniform recommendations for surveillance colonoscopy for these lesions.

Analysis of predictive factors for R0 resection and immediate bleeding of cold snare polypectomy in colonoscopy

Background

Factors associated with efficacy and safety of cold snare polypectomy (CSP) are not well established. The aim is to elucidate the predictors of R0 resection and immediate bleeding of CSP.

Methods

We retrospectively reviewed a database of patients who underwent CSP for subcentimetric polyps at the University of Tokyo Hospital in Japan. Using the data regarding the characteristics of patients and polyps, such as location, size, and macroscopic appearance; use of narrow band imaging with magnification (NBI-M); and endoscopists’ experience, we revealed the predictive factors associated with R0 resection and immediate post-CSP bleeding by univariate and multivariate analyses.

Results

In total, 399 polyps, in 200 patients without antithrombotics, were removed. Failure of tissue retrieval was noted in 4% of resected lesions. There was no intramucosal carcinoma observed. The overall rate of R0 resection was 46%. Multivariate analysis elucidated that the observation of the polyp with NBI-M was an independent predictor associated with R0 resection (odds ratio [OR] 1.90; p = 0.024). Although immediate post-CSP bleeding occurred in 19 polyps (4.8%), no delayed bleeding or perforation was observed. Multivariate analysis revealed protruded lesion as an independent risk factor for immediate bleeding (OR 3.54; p = 0.018).

Conclusions

A higher rate of R0 resection with CSP can be achieved by performing colonoscopy with NBI-M, than with white-light imaging. Macroscopic protruding appearance of a polyp is a risk factor for immediate bleeding.

BEST POLYPECTOMY TECHNIQUE FOR SMALL AND DIMINUTIVE COLORECTAL POLYPS: A SYSTEMATIC REVIEW AND META-ANALYSIS

BACKGROUND

Polypectomy of colorectal polyps is the mainstay of colorectal cancer prevention. Identification of the best polypectomy technique is imperative.

OBJECTIVE

This review aims at comparing efficacy of nine different resection methods for small colorectal polyps (<10 mm).

METHODS

We searched and selected only randomized controlled trials. Primary outcome was complete resection rates of small polyps by histological eradication. Secondary outcomes were: adverse events, retrieval tissue failures rates and duration of procedure.

RESULTS

Eighteen trials including 3215 patients and 5223 polyps were analysed. Overall, cold polypectomy had a significantly shorter time of procedure than hot polypectomy (RD -5.92, 95%CI -9.90 to -1.94, P<0.05), with no statistical difference on complete histological eradication (RD 0.08, 95%CI -0.03 to 0.19, P>0.05). Regarding cold polypectomy techniques, cold snare was found superior to cold forceps on complete and en-bloc resection rates and less time consuming. When comparing endoscopic mucosal resection (EMR) with hot-snare and cold-snare, the latter showed no-inferiority on histological eradication, adverse events or retrieval tissue failure rates.

CONCLUSION

Cold polypectomy is the best technique for resection of small colorectal polyps. Among cold methods, dedicated cold snare was found superior on histological eradication. Cold snare endoscopic mucosal resection might be considered an option for polyps from 5 to 9 mm.

Risk of delayed bleeding before and after implementation of cold snare polypectomy in a screening colonoscopy setting

Background and study aims  Cold snare polypectomy (CSP) is considered to be effective in reducing risk of delayed bleeding but randomized trials fail to support this owing to the small sample size. The current study aimed to compare risk of delayed bleeding before and after implementation of CSP in a screening colonoscopy setting. Patients and methods  This study retrospectively analyzed a prospectively maintained screening colonoscopy database in a university hospital in Taiwan. We compared the rate of delayed bleeding before and after implementation within similar periods (18 months and 15 months) and the respective number of polypectomies (1,304 and 1,255) performed to remove small and diminutive polyps. The main outcome measurement was delayed bleeding within the two periods. Multivariate analysis was performed to adjust for major confounders. Results  A total of 1,304 and 1,225 subjects received hot snare polypectomy (HSP) and CSP in two separate periods, respectively. Compared with the HSP, the CSP had a lower rate of delayed bleeding (0.1 % vs . 1.1 %, P  < 0.001), severe bleeding (0 % vs. 0.7 %, P  < 0.01), need for second-look colonoscopy (0 % vs. 0.8 %, P  < 0.01), and emergency service visits (0.1 % vs . 1.0 %, P  < 0.01). Total procedure time (12.60 ± 11.45 vs . 16.48 ± 14.27 min/person, P  < 0.01) and duration of hospital stay (1.18 ± 0.50 vs . 1.53 ± 5.78 hour/person, P  < 0.03) were also shorter after CSP implementation. Multivariate analysis showed that HSP was an independent risk factor for delayed bleeding after adjusting for age, gender, and number of polyps (adjusted odds ratio 14.4;95 % confidence interval = 1.88 - 110.6). Conclusion  Implementation of CSP significantly reduces risk of delayed bleeding associated with removing small and diminutive polyps in screening colonoscopy.

Endoscopic prediction of advanced histology in diminutive and small colorectal polyps

BACKGROUND AND AIM

Most polyps detected during colonoscopies are diminutive or small, and they rarely have advanced histology. Real-time prediction of advanced histology would help clinicians to assess the need for pathological evaluation. Here, we investigated endoscopic predictors of advanced histology in diminutive and small polyps.

METHODS

Consecutive patients with adenomatous polyps (<10 mm) removed endoscopically from January 2013 to December 2014 at a single tertiary cancer center were eligible for inclusion. Two endoscopists reviewed all endoscopic images to identify significant findings associated with advanced histology using multivariate models. The sensitivity, specificity, and negative predictive value of the identified endoscopic predictors for advanced histology were calculated.

RESULTS

Of 6170 polyps (4746 diminutive) removed from 2611 patients, 320 (5.2%) showed advanced histology, including five submucosal invasive cancers. In multivariate analysis, advanced histology was significantly associated with the following: loss of lobulation (odds ratio [OR] 61.7; 95% confidence interval [95% CI]: 19.1-199.0); heterogeneity in mucosal patterns (OR 29.0; 95% CI: 14.6-57.3); non-polypoid growth (OR 15.7; 95% CI: 4.4-55.5); white spots (OR 13.5; 95% CI: 7.8-23.5); and surface redness (OR 6.6; 95% CI: 3.0-14.5); and irregular capillary pattern (OR 4.8; 95% CI: 2.5-9.1). These significant predictors successfully predicted all submucosal invasive cancers as advanced histology. The sensitivity, specificity, and negative predictive values were 37.2%, 97.8%, and 96.6%.

CONCLUSIONS

We identified six endoscopic predictors for advanced histology in diminutive or small colon polyps. Diminutive and small polyps lacking these predictors would not be considered to have advanced histology.

Quality measures improving endoscopic screening of colorectal cancer: a review of the literature

INTRODUCTION

Colorectal cancer (CRC) is a major health-care problem all over the world and CRC screening is effective in reducing mortality and increasing the 5-year survival. Colonoscopy has a central role in CRC screening. It can be performed as a primary test, as a recall policy after a positive result of another screening test, and for surveillance. Since effectiveness of endoscopic screening depends on adequate detection and removal of colonic polyps, consistent quality measures, which are useful in enhancing the diagnostic yield of examination, are essential. Areas covered: The aim of this review is to analyze current evidence from literature supporting quality measures able to refine endoscopic screening of colorectal cancer. Expert commentary: Quality measures namely a) time slot allotted to colonoscopy, b) assessment of indication, c) bowel preparation, d) Cecal intubation, e) withdrawal time, f) adenoma detection rate, g) proper management of lesions (polypectomy technique, polyps retrieval rate and tattooing of resection sites), and h) adequate follow-up intervals play a key role in identifying malignant and at-risk lesions and improving the outcome of screening. Adherence to these quality measures is critical to maximize the effectiveness of CRC screening, as well as, a proper technique of colonoscopy and a quality report of the procedure. Among all recommended measures, adenoma detection rate is the most important and must be kept above the recommended quality threshold by all physicians practicing in the setting of screening.

Challenging management of familial adenomatous polyposis with advanced colorectal cancer: laparoscopic partial resection and cold snare polypectomy

Background and study aims  Prophylactic extended colectomy may be indicated because most surgically untreated patients with familial adenomatous polyposis (FAP) develop colorectal cancer (CRC) in their lifetime. However, some patients refuse to undergo surgery to avoid degradation of their quality of life. We report that FAP is controllable with laparoscopic partial resection and postoperative polypectomy even when complicated by advanced CRC. We also discuss the utility of cold snare polypectomy for resection of polyps.

Management and risk factors for incomplete resection associated with jumbo forceps polypectomy for diminutive colorectal polyps: a single-institution retrospective study

BACKGROUND

Cold forceps polypectomy is simple and widely used in clinical practice. However, there are concerns about the risk of incomplete resection using this technique. In recent years, it has been reported that polypectomy with jumbo forceps (JF) is an effective treatment modality for diminutive polyps (DPs) because JF are able to remove large tissue samples with the combined advantage of a higher complete histological resection rate for DPs than standard forceps. To our knowledge, no studies have evaluated the risk factors for incomplete resection when polypectomy with JF is performed for DPs.

METHODS

From among 1129 DPs resected using JF at Hiroshima City Asa Citizens Hospital between November 2015 and December 2016, we retrospectively evaluated the clinical outcomes of 999 tumors with known histopathology and investigated the relationship between incomplete resection and clinicopathological factors.

RESULTS

Most lesions [985 (87%)] were low-grade dysplasia and 14 (1%) were high-grade dysplasia. The en bloc resection rate was 92% (918/999) and the histological en bloc resection rate was 78% (777/999). Multivariate analysis showed that the significant independent predictors of incomplete resection were tumor size ≥ 4 mm [odds ratio (OR) 3.8; 95% confidence interval (CI) 2.65-5.37; p < 0.01], non-tangential direction of forceps in relation to the tumor (OR 1.73; 95% CI 1.21-2.45; p < 0.01), and lack of muscularis mucosae in the pathological specimen (OR 15.7; 95% CI 9.16-27.7; p < 0.01).

CONCLUSIONS

This study identified significant independent predictors of incomplete resection of DPs which may be helpful when planning polypectomy with JF.

Efficacy and safety of cold forceps polypectomy utilizing the jumbo cup: a prospective study

Background/Aims

There are few prospective studies on cold forceps polypectomy (CFP) using jumbo cup forceps. Therefore, we examined patients with diminutive polyps (5 mm or smaller) treated with CFP using jumbo cup forceps to achieve an adenoma-free colon and also assessed the safety of the procedure and the recurrence rate of missed or residual polyp after CFP by performing follow-up colonoscopy 1 year later.

Methods

We included patients with up to 5 adenomas removed at initial colonoscopy and analyzed data from a total of 361 patients with 573 adenomas. One-year follow-up colonoscopy was performed in 165 patients, at which 251 lesions were confirmed.

Results

The one-bite resection rate with CFP was highest for lesions 3 mm or smaller and decreased significantly with increasing lesion size. Post-procedural hemorrhage was observed in 1 of 573 lesions (0.17%). No perforation was noted. The definite recurrence rate was 0.8% (2/251 lesions). The probable recurrence rate, which was defined as recurrence in the same colorectal segment, was 17%. Adenoma-free colon was achieved in 55% of patients at initial resection. Multivariate analysis revealed that achievement of an adenoma-free colon was significantly associated with number of adenomas and years of endoscopic experience.

Conclusions

CFP using jumbo biopsy forceps was safe and showed a high one-bite resection rate for diminutive lesions of 3 mm or smaller. The low definite recurrence rate confirms the reliability of CFP using jumbo biopsy forceps. Number of adenomas and years of endoscopic experience were key factors in achieving an adenoma-free colon.

Complete polypectomy and early detection and management of residual disease to reduce the risk of interval colorectal cancers

Advances in colorectal polyp detection and resection methods aim to reduce interval cancer rates. Complete polypectomy is essential to reduce the risk of early recurrence and the development of interval cancers. To achieve this, polyps must first be correctly identified and then completely excised. This article reviews current adenoma detection methods in use and the management of residual disease.

Resection depth and layer of cold snare polypectomy versus endoscopic mucosal resection

BACKGROUND

Cold snare polypectomy (CSP) has not undergone sufficient histopathological evaluation. This study aimed to clarify the histopathological features of CSP specimens, including resection depth and layer, as compared with endoscopic mucosal resection (EMR).

METHODS

Polyps were recruited retrospectively. Sessile, semi-pedunculated, and 0-IIa polyps of ≤ 9 mm were selected by propensity score matching and classified as either a complete resection or one with an unevaluable/positive (X/+) margin. Resection depth and layer were estimated and the risk factors for an X/+ margin were evaluated.

RESULTS

A total of 1072 polyps were enrolled. After matching, 184 polyp pairs were selected. An X/+ margin was seen in 105/184 (57%) vs. 70/184 (38%) CSP vs. EMR specimens (p < 0.001): specimen damage was 53/184 (29%) vs. 30/184 (16%) (p < 0.01) and vertical margin (VM) X/+ was 11/184 (6%) vs. 2/184 (1%) (p < 0.05). Among 193 completely resected specimens, resection depth from the muscularis mucosae in CSP vs. EMR was 76 vs. 338 µm (p < 0.001) and resection layer was the submucosa in 7/79 (9%) vs. 105/114 (92%) (p < 0.001). In multivariate analysis, CSP was a risk factor for procedure-associated VMX/+ [odds ratio (OR) 6.80, 95% confidence interval (CI) 1.33-34.69, p < 0.05]. Sessile serrated adenoma/polyp (SSA/P) was a risk factor for VMX/+ margin in CSP specimens (OR 58.36, 95% CI 7.45-456.96, p < 0.001).

CONCLUSIONS

SSA/P and colorectal cancer may not be suitable for CSP adoption.

A comparison of the resection rate for cold and hot snare polypectomy for 4-9 mm colorectal polyps: a multicentre randomised controlled trial (CRESCENT study)

OBJECTIVE

To investigate the success rate of cold snare polypectomy (CSP) for complete resection of 4-9 mm colorectal adenomatous polyps compared with that of hot snare polypectomy (HSP).

DESIGN

A prospective, multicentre, randomised controlled, parallel, non-inferiority trial conducted in 12 Japanese endoscopy units. Endoscopically diagnosed sessile adenomatous polyps, 4-9 mm in size, were randomly assigned to the CSP or HSP group. After complete removal of the polyp using the allocated technique, biopsy specimens from the resection margin after polypectomy were obtained. The primary endpoint was the complete resection rate, defined as no evidence of adenomatous tissue in the biopsied specimens, among all pathologically confirmed adenomatous polyps.

RESULTS

A total of 796 eligible polyps were detected in 538 of 912 patients screened for eligibility between September 2015 and August 2016. The complete resection rate for CSP was 98.2% compared with 97.4% for HSP. The non-inferiority of CSP for complete resection compared with HSP was confirmed by the +0.8% (90% CI -1.0 to 2.7) complete resection rate (non-inferiority p<0.0001). Postoperative bleeding requiring endoscopic haemostasis occurred only in the HSP group (0.5%, 2 of 402 polyps).

CONCLUSIONS

The complete resection rate for CSP is not inferior to that for HSP. CSP can be one of the standard techniques for 4-9 mm colorectal polyps. (Study registration: UMIN000018328).

Efficacy and safety of cold versus hot snare polypectomy for resecting small colorectal polyps: Systematic review and meta-analysis

BACKGROUND AND AIM

Safety and effectiveness of cold snare polypectomy (CSP) compared with hot snare polypectomy (HSP) has been reported. The aim of the present study is to carry out a meta-analysis of the efficacy and safety of HSP and CSP.

METHODS

Randomized controlled trials were reviewed to compare HSP with CSP for resecting small colorectal polyps. Outcomes reviewed include complete resection rate, polyp retrieval, delayed bleeding, perforation and procedure time. Outcomes were documented by pooled risk ratios (RR) with 95% confidence intervals (CI) using the Mantel-Haenszel random effect model.

RESULTS

Eight studies were reviewed in this meta-analysis, including 1665 patients with 3195 polyps. Complete resection rate using HSP was similar to CSP (RR: 1.02, 95% CI: 0.98-1.07, P = 0.31). Polyp retrieval after HSP was similar to CSP (RR: 1.00, 95% CI: 1.00-1.01, P = 0.60). Delayed bleeding rate after HSP was higher than after CSP, although not significantly (patient basis: RR: 7.53, 95% CI: 0.94-60.24, P = 0.06; polyp basis: RR: 7.35, 95% CI: 0.91-59.33, P = 0.06). Perforation was not reported in all eight studies. Total colonoscopy time for HSP was significantly longer than CSP (mean difference 7.13 min, 95% CI: 5.32-8.94, P < 0.001). Specific polypectomy time for HSP was significantly longer than CSP (mean difference 30.92 s, 95% CI: 9.15-52.68, P = 0.005).

CONCLUSION

This meta-analysis shows significantly shorter procedure time using CSP compared with HSP. CSP tends toward less delayed bleeding compared with HSP. We recommend CSP as the standard treatment for resecting small benign colorectal polyps.

Comparison of cold and hot snaring polypectomy for small colorectal polyps: study protocol for a randomized controlled trial

Background

Colorectal cancer remains a considerable challenge in healthcare nowadays. Most patients’ disease develops via the adenoma–carcinoma sequence; colonoscopy with polypectomy effectively reduces both mortality and incidence by removing precancerous adenomas. Previous studies showed that polypectomy without electrocautery (cold snaring polypectomy) is a safe and time-saving procedure to manage polyps < 10 mm. However, randomized controlled trials have failed to prove the superiority of cold snaring polypectomy for reducing the risk of delayed bleeding in comparison with hot snaring polypectomy, generally because of their low statistical power that was limited by sample sizes. In this study, we aim to compare the risk of delayed bleeding following cold and hot snaring polypectomy based on a large sample size.

Methods

This is a prospective multicentre randomized controlled trial to compare cold and hot snaring polypectomy for the treatment of small colorectal polyps. A total of 4258 patients with small polyps (4–10 mm) will be randomized 1:1 to each group. Colonoscopy and polypectomy will be performed by 17 experienced endoscopists at six study sites. The randomization will be performed via an online website. Pathological examination using image-enhanced endoscopy with either narrow-band imaging or chromoendoscopy will be conducted to confirm optically and histologically that complete resections have been achieved, respectively. The primary outcome measurement is the risk of delayed bleeding. The secondary outcome measurements include the number of hemoclip applications, complete eradication confirmed optically and histologically, tissue retrieval rate, procedure time, emergency unit visits, and any adverse events such as immediate bleeding or perforation.

Discussion

We hypothesize that cold snaring polypectomy can reduce the risk of delayed bleeding by avoiding thermal injury. In addition, this study will also compare cold and hot snaring polypectomy in terms of the complete eradication rate and procedure time. Based on data collected, we will demonstrate that cold snaring polypectomy is a safe, effective, and economic procedure for small colorectal polyps. The results will also provide additional data on which to develop recommendations for treating small colorectal polyps.

Trial registration

ClinicalTrials.gov, NCT03373136. Registered on 29 November 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2743-z) contains supplementary material, which is available to authorized users.

Impact of 2 generational improvements in colonoscopes on adenoma miss rates: results of a prospective randomized multicenter tandem study

BACKGROUND AND AIMS

Numerous randomized studies have shown that changing certain features of colonoscopes, usually incorporated when switching from one endoscope generation to the next, mostly do not increase adenoma yield. There is, however, indirect evidence that it may be necessary to skip one instrument generation (ie, changing from one generation to the next but one) to achieve this effect.

METHODS

We compared the latest-generation colonoscopes from one company (Olympus Exera III, 190-C) with the next to last one (Olympus 160/5-C) in a prospective multicenter study randomized for the order of colonoscopes in a tandem fashion, involving 2 different examiners. Patients with increased risk for colorectal neoplasia undergoing colonoscopy (positive fecal occult blood test, personal/familial history of colorectal cancer/adenoma, rectal bleeding, recent change in bowel movements) were included. The primary outcome was the adenoma miss rate with the 190 (190-C) colonoscope in comparison with the 160/5 colonoscope (160/5-C).

RESULTS

A total of 856 patients (48.8% male; mean age, 58.3 years) with a personal (41%) or family (38%) history of colorectal neoplasia, rectal bleeding (19%), and other indications were included. Of the 429 patients in the 190-C first group, 16.6% (95% confidence interval [CI], 13.0%-20.1%) had at least one adenoma missed during the first procedure, compared with 30.2% (95% CI, 25.9%-34.6%) in the group with 160/5-C first (P < .001). Similarly, the adenoma detection rate during the first colonoscopy was 43.8% versus 36.5% (P = .030) for 190-C versus 160/5-C, respectively.

CONCLUSIONS

This randomized tandem trial showed lower adenoma miss rates and higher adenoma detection rates for the newer 190 colonoscopes compared with the 160/5 series. These results suggest that it takes multiple improvements, such as those implemented over 2 instrument generations, before an effect on adenoma (miss) rate can be observed. (Study registration number: ISRCTN 2010-A01256-33.).

Sessile Serrated Adenomas: How to Detect, Characterize and Resect

Serrated polyps are important contributors to the burden of colorectal cancers (CRC). These lesions were once considered to have no malignant potential, but currently up to 30% of all CRC are recognized to arise from the serrated neoplasia pathway. The primary premalignant lesions are sessile serrated adenomas/polyps (SSA/Ps), although traditional serrated adenomas are relatively uncommon. Compared to conventional adenomas, SSA/Ps are morphologically subtle with indistinct borders, may be difficult to detect endoscopically, are more prevalent than previously thought, are associated with synchronous and metachronous advanced neoplasia, and have a higher risk of incomplete resection. Although many lesions remain “dormant,” progressive disease is associated with the development of dysplasia and more rapid progression to CRC. As a result, SSA/Ps are strongly implicated in the development of interval cancers. These factors represent unique challenges that require a meticulous approach to their management. In this review, we summarize the contemporary literature on the characterization, detection and resection of SSA/Ps.

Hot snare polypectomy with or without saline solution/epinephrine lift for the complete resection of small colorectal polyps

BACKGROUND AND AIMS

The criteria for a standard polypectomy technique for complete removal of small colorectal polyps has not yet been established. This study aimed to compare the complete resection rate of hot snare polypectomy (HSP) with that of EMR for small, sessile, or flat polyps.

METHODS

Patients with 5- to 9-mm non-pedunculated colorectal polyps were prospectively randomized to the HSP or EMR group. The presence of residual polyps was assessed by performing histologic assessment of 4-quadrant forceps biopsy specimens taken from the edges of the polypectomy site. The primary outcome was the complete resection rate after HSP or EMR; the secondary outcomes were the proportion of procedure-related adverse events and specimen-loss rate. Sample size was estimated using a superiority trial design. We assumed that the complete resection rate of the EMR group would be at least 8% higher than that of the HSP group.

RESULTS

A total of 382 polyps in 269 patients were assessed and randomly assigned to each method using 4 × 4 block randomization. Of these, 353 polyps were finally analyzed based on the pathology results. The mean polyp size was 6.3 ± 1.3 mm. The complete resection rate did not differ between the HSP and EMR groups (88.4% [152/172] vs 92.8% [168/181], respectively; P = .2). The intraprocedural bleeding rate, immediately after polypectomy, was significantly higher in the HSP group than in the EMR group (5.2% vs 0.6%, respectively; P = .009). However, clinically significant bleeding and tissue retrieval failure rates did not differ between the groups. In the multivariate logistic regression analysis, sessile serrated adenoma/polyps or hyperplastic polyps were almost 3 times (odds ratio, 2.824; 95% confidence interval, 1.03-7.75; P = .044) more likely to be incompletely resected compared with other conventional adenomatous polyps. Except for pathology, we found no significant independent predictors for incomplete resection.

CONCLUSION

EMR for small non-pedunculated colorectal polyps is not superior to HSP in terms of complete resection or safety. Both methods can be performed according to the endoscopist's preference. (Clinical trial registration number: KCT0001640; cris.nih.go.kr.).

Should hot biopsy forceps be abandoned for polypectomy of diminutive colorectal polyps?

Standardized approach to polypectomy of diminutive colorectal polyps (DCPs) is lacking since cold biopsy forceps have been associated with high levels of recurrence, hot biopsy forceps are considered inadequate and risky and cold snaring is currently under investigation for its efficacy and safety. This has led to confusion and a gap in clinical practice. This article discusses the usefulness and contemporary practical applicability of hot biopsy forceps and provides well-intentioned criticism of the new European guidelines for the treatment of DCPs. Diminutive colorectal polyps are a source of frustration for the endoscopist since their small size is accompanied by a considerable risk of premalignant neoplasia and a small but non-negligible risk of advanced neoplasia and even cancer. Since the proportion of diminutive colorectal polyps is substantial and exceeds that of larger polyps, their effective removal poses a considerable workload and a therapeutic challenge. During the last decade, the introduction of cold snaring to routine endoscopy practice has attempted to overcome the use of prior techniques, such as hot biopsy forceps. It is important to recognize that with the exception of endoscopic methods that are obviously unsafe and inadequate to serve their purpose, all other interventional endoscopic methods are operator-dependent in the sense that specific expertise and training are obligatory for the success of any therapeutic intervention. Since relevant publications on hot biopsy forceps are still in favor of its careful use, as it has not yet demonstrated inferiority compared with newer techniques, it would be prudent for any medical practitioner to evaluate the available tools and judge any new proposed technique based on the evidence before it is adopted.

Challenges associated with the pathological diagnosis of colorectal tumors less than 10 mm in size

Various techniques including cold snare polypectomy and endoscopic mucosal resection are used for the removal of small colorectal polyps. Specimens of resected polyps are prepared in pathology laboratories and analyzed to make a pathological diagnosis. However, reports on how different resection methods influence the pathological diagnosis are limited. This article discusses the problems associated with the failure of polyp retrieval and fragmentation of small specimens during collection and the effects of certain parameters on the pathological diagnosis, particularly with regard to surgical margins. In the future, although pathologists are expected to encounter problems as a result of minor findings that are not clinically problematic, relatively rare cases such as submucosal invasion by a small carcinoma should not be overlooked.

Cold EMR of large sessile serrated polyps at colonoscopy (with video)

BACKGROUND AND AIMS

The optimal technique for the resection of sessile serrated polyps (SSPs) is unknown, with established limitations and risks with conventional polypectomy. Although cold snare polypectomy is safe, the efficacy of piecemeal resection for large lesions is untested. In this study we evaluate the safety and efficacy of cold EMR for large SSPs.

METHODS

Patients presenting for elective colonoscopy at an academic endoscopy center with 1 or more SSPs ≥10 mm in size were enrolled, excluding those on anticoagulant or antiplatelet therapy other than aspirin. Lesions were resected with a cold EMR technique comprising submucosal injection of succinylated gelatin and dilute methylene blue before piecemeal cold snare resection of all visible polyp with a margin of normal tissue. Outcomes were the presence of residual serrated neoplasia in biopsy specimens from the defect margin and findings on surveillance colonoscopy.

RESULTS

Cold EMR was performed on 163 SSPs during 105 procedures in 99 patients (97% women; median age, 57 years). The mean size was 17.5 mm: 61 SSPs were ≥20 mm and 13 SSPs ≥30 mm, and 97.5% were in the proximal colon. Cytologic dysplasia was present in 2 (1.2%). Margin biopsy specimens were positive in 2 lesions (1.2%). Surveillance colonoscopy for 82% of lesions (median, 5 months) showed residual serrated tissue in 1, treated with cold snare, but no evidence of recurrence in the remainder. Minor adverse events were seen in 3 patients; no delayed bleeding was observed.

CONCLUSIONS

Cold EMR is a safe and effective method for the removal of large SSPs.