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)

Circumferential submucosal incision prior to endoscopic mucosal resection versus conventional endoscopic mucosal resection for colorectal lesions with endoscopic features of sessile serrated lesions

BACKGROUND AND AIMS

Sessile serrated lesions (SSLs) are more prone to incomplete resection than conventional adenomas. This study evaluated whether circumferential submucosal incision prior to endoscopic mucosal resection (CSI-EMR) can increase the rate of complete and en bloc resections of colorectal lesions with endoscopic features of SSL.

METHODS

Retrospective analyses and propensity score matching were performed for the resection of colorectal lesions ≥ 10 mm with endoscopic features of SSL.

RESULTS

After 1:1 ratio matching, 127 lesions in the CSI-EMR group and 127 in the EMR group were selected for analysis. The median size of the lesions was 15 mm (IQR 12-16) in both groups. There was no significant difference in either the complete resection rate or en bloc resection rate between CSI-EMR and EMR groups (96.9% vs. 92.9%, P = 0.155; 92.1% vs. 89.0%, P = 0.391). By contrast, the R0 resection rate was significantly higher in the CSI-EMR group than in the EMR group (89.8% vs. 59.8%, P < 0.001). The median procedure time was significantly longer in the CSI-EMR group than in the EMR group (6.28 min vs. 2.55 min, P < 0.001), whereas there was no significant difference between the two groups in the incidence of adverse events or recurrence rate. Multivariate analysis showed that CSI-EMR was the only factor significantly associated with R0 resection (P < 0.001).

CONCLUSIONS

For colorectal lesions with endoscopic features of SSL, CSI-EMR does not increase the complete or en bloc resection rate, but does increase the R0 resection rate. The procedure time is longer for CSI-EMR than EMR. The association of CSI-EMR with R0 resection and non-recurrence should be further evaluated.

Evidence-based clinical practice guidelines for management of colorectal polyps

BACKGROUND

The Japanese Society of Gastroenterology (JSGE) published ''Daicho Polyp Shinryo Guideline 2014'' in Japanese and a part of this guideline was published in English as "Evidence-based clinical practice guidelines for management of colorectal polyps" in the Journal of Gastroenterology in 2015. A revised version of the Japanese-language guideline was published in 2020, and here we introduce a part of the contents of revised version.

METHODS

The guideline committee discussed and drew up a series of clinical questions (CQs). Recommendation statements for the CQs were limited to items with multiple therapeutic options. Items with established conclusions that had 100% agreement with previous guidelines (background questions) and items with no (or old) evidence that are topics for future research (future research questions: FRQs) were given descriptions only. To address the CQs and FRQs, PubMed, ICHUSHI, and other sources were searched for relevant articles published in English from 1983 to October 2018 and articles published in Japanese from 1983 to November 2018. The Japan Medical Library Association was also commissioned to search for relevant materials. Manual searches were performed for questions with insufficient online references.

RESULTS

The professional committee created 18 CQs and statements concerning the current concept and diagnosis/treatment of various colorectal polyps, including their epidemiology, screening, pathophysiology, definition and classification, diagnosis, management, practical treatment, complications, and surveillance after treatment, and other colorectal lesions (submucosal tumors, nonneoplastic polyps, polyposis, hereditary tumors, ulcerative colitis-associated tumors/carcinomas).

CONCLUSIONS

After evaluation by the moderators, evidence-based clinical practice guidelines for management of colorectal polyps were proposed for 2020. This report addresses the therapeutic related CQs introduced when formulating these guidelines.

Incomplete endoscopic resection of colorectal polyps: a prospective quality assurance study

BACKGROUND

 Endoscopic screening with polypectomy has been shown to reduce colorectal cancer incidence in randomized trials. Incomplete polyp removal and subsequent development of post-colonoscopy cancers may attenuate the effect of screening. This study aimed to quantify the extent of incomplete polyp removal.

METHODS

 We included patients aged 50-75 years with nonpedunculated polyps ≥ 5 mm removed during colonoscopy at four hospitals in Norway. To evaluate completeness of polyp removal, biopsies from the resection margins were obtained after polypectomy. Logistic regression models were fitted to identify factors explaining incomplete resection.

RESULTS

 246 patients with 339 polyps underwent polypectomy between January 2015 and June 2017. A total of 12 polyps were excluded due to biopsy electrocautery damage, and 327 polyps in 246 patients (mean age 67 years [range 42-83]; 52 % male) were included in the analysis. Overall, 54 polyps (15.9 %) in 54 patients were incompletely resected. Histological diagnosis of the polyp (sessile serrated lesions vs. adenoma, odds ratio [OR] 10.9, 95 % confidence interval [CI] 3.9-30.1) and polyp location (proximal vs. distal colon, OR 2.8, 95 %CI 1.0-7.7) were independent risk factors for incomplete removal of polyps 5-19 mm. Board-certified endoscopists were not associated with lower rates of incomplete resection compared with trainees (14.0 % vs. 14.2 %), OR 1.0 (95 %CI 0.5-2.1).

CONCLUSION

Incomplete polyp resection was frequent after polypectomy in routine clinical practice. Serrated histology and proximal location were independent risk factors for incomplete resection. The performance of board-certified gastroenterologists was not superior to that of trainees.

Effect of Instruction on Preventing Delayed Bleeding after Colorectal Polypectomy and Endoscopic Mucosal Resection

Background: The frequency of delayed bleeding after colorectal polypectomy has been reported as 0.6–2.8%. With the increasing performance of polypectomy under continuous use of antithrombotic agents, care is required regarding delayed post-polypectomy bleeding (DPPB). Better instruction to educate endoscopists is therefore needed. We aimed to evaluate the effect of instruction and factors associated with delayed bleeding after endoscopic colorectal polyp resection. Methods: This single-center, retrospective study was performed to assess instruction in checking complete hemostasis and risk factors for onset of DPPB. The incidence of delayed bleeding, comorbidities, and medications were evaluated from medical records. Characteristics of historical control patients and patients after instruction were compared. Results: A total of 3318 polyps in 1002 patients were evaluated. The control group comprised 1479 polyps in 458 patients and the after-instruction group comprised 1839 polyps in 544 patients. DPPB occurred in 1.1% of polyps in control, and 0.4% in after-instruction. Instruction significantly decreased delayed bleeding, particularly in cases with antithrombotic agents. Hot polypectomy, clip placement, and use of antithrombotic agents were significant independent risk factors for DPPB even after instruction. Conclusion: The rate of delayed bleeding significantly decreased after instruction to check for complete hemostasis. Even after instruction, delayed bleeding can still occur in cases with antithrombotic agents or hot polypectomy.

Cold snare polypectomy for large sessile serrated lesions is safe but follow-up is needed: a single-centre retrospective study

Background and Aim

Cold snare polypectomy (CSP) is growing in popularity due to its safety and convenience. Its indication is benign tumours such as adenoma and sessile serrated lesions (SSLs) <10 mm in size. CSP for SSLs ≥10 mm in size has not been well examined. In this study, we aimed the feasibility of this treatment regarding therapeutic results and local recurrence.

Methods

This was a single‐centre retrospective cohort study. We reviewed SSLs with or without dysplasia of 10–20 mm that were resected by CSP from 2014 to 2020. All tumours were diagnosed endoscopically as SSLs without dysplasia before CSP with the help of magnifying narrow band imaging or blue laser imaging. We analysed the lesion characteristics, en bloc resection, histopathological diagnosis, adverse events and local recurrence. We analysed risk factors for recurrence, comparing recurrent lesions to non‐recurrent lesions. We also compared risk factors for lesions 10–14 mm in size to those for lesions 15–20 mm in size.

Results

We analysed 160 lesions in 100 patients (M_age ± SD = 67.7 ± 10.1 years). The polyp size (M ± SD) was 11.8 ± 2.8 mm, and the en bloc resection rate was 60.0% (96 cases). The rates of massive perioperative haemorrhage, postoperative haemorrhage and perforation were 1.3%, 0% and 0%, respectively. Regarding histopathological diagnosis, two (1.2%) cases showed SSLs with high‐grade dysplasia. The recurrence rate in 101 lesions with a median follow‐up period of 18 months (interquartile range 12–24 months) was 5.0%. There were no significant risk factors such as tumour size, location, morphology and so on in terms of recurrence. All recurrent cases could be resected by repeat CSP. The recurrence rates of lesions 10–14 mm in size and 15–20 mm in size were 4.7% and 6.3%, respectively (p = 0.713).

Conclusion

CSP of SSLs ≥10 mm in size according to magnifying endoscopic diagnosis was safe and promising, but the rate of recurrence was slightly high, meaning that close follow‐up is required.

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.

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).

Efficacy and safety of cold-snare endoscopic mucosal resection for colorectal adenomas 10 to 14 mm in size: a prospective observational study

BACKGROUND AND AIMS

Cold-snare endoscopic mucosal resection (CS-EMR) has been adapted in a piecemeal fashion as a safe and effective procedure for resection of colorectal polyps ≥10 mm. However, few data are available on en bloc CS-EMR for adenomas of 10 to 14 mm. Thus, this study evaluated the efficacy and safety of CS-EMR for these colorectal adenomas.

METHODS

In this single-arm, prospective, observational study, patients with at least 1 slightly elevated and sessile colorectal adenoma measuring 10 to 14 mm were recruited to undergo CS-EMR. The primary outcome was histological complete resection rate by CS-EMR, which was defined as en bloc resection, with a pathologically negative vertical margin and no neoplastic tissue obtained from 4 quadrants of the mucosal defect margin. Secondary outcomes were en bloc resection rate by CS-EMR, failure rate of CS-EMR, and the incidence of adverse events.

RESULTS

A total of 80 polyps from 72 patients were included. CS-EMR failed in 11 lesions (13.7%), all of which were resected using a high-frequency electric current. The rates of en bloc resection and histologic complete resection by CS-EMR were 82.5% (66 of 80) and 63.8% (51 of 80), respectively. No bleeding occurred during the CS-EMR procedure, and there was no delayed bleeding or perforation at the site where CS-EMR was performed.

CONCLUSIONS

CS-EMR can be safely performed in an en bloc fashion for some colorectal adenomas measuring 10 to 14 mm. However, there is room for improvement regarding the resectability and evaluation of the vertical margin after CS-EMR. (Clinical trial registration number: UMIN000031248.).

Anticoagulation and antiplatelet management in gastrointestinal endoscopy: A review of current evidence

The role of endoscopic procedures, in both diagnostic and therapeutic purposes is continually expanding and evolving rapidly. In this context, endoscopists will encounter patients prescribed on anticoagulant and antiplatelet medications frequently. This poses an increased risk of intraprocedural and delayed gastrointestinal bleeding. Thus, there is now greater importance on optimal pre, peri and post-operative management of anticoagulant and/or antiplatelet therapy to minimise the risk of post-procedural bleeding, without increasing the risk of a thromboembolic event as a consequence of therapy interruption. Currently, there are position statements and guidelines from the major gastroenterology societies. These are available to assist endoscopists with an evidenced-based systematic approach to anticoagulant and/or antiplatelet management in endoscopic procedures, to ensure optimal patient safety. However, since the publication of these guidelines, there is emerging evidence not previously considered in the recommendations that may warrant changes to our current clinical practices. Most notably and divergent from current position statements, is a growing concern regarding the use of heparin bridging therapy during warfarin cessation and its associated risk of increased bleeding, suggestive that this practice should be avoided. In addition, there is emerging evidence that anticoagulant and/or antiplatelet therapy may be safe to be continued in cold snare polypectomy for small polyps (< 10 mm).

Polypectomy Techniques

Polyps in the upper and lower gastrointestinal tract can be premalignant or malignant lesions that can be treated endoscopically in early stages to prevent morbidity and more invasive procedures. This article critically reviews the techniques available and provides recommendations for endoscopic polypectomy.

Hot snare polypectomy versus endoscopic mucosal resection for small colorectal polyps: a randomized controlled trial

BACKGROUND AND AIMS

This study was performed to compare endoscopic mucosal resection (EMR) with hot snare polypectomy (HSP) in terms of the complete resection rate and the incidence of adverse events for resecting small (5-10 mm) colorectal polyps.

METHODS

Small colorectal polyps (5-10 mm) with neoplastic features were randomly allocated to either the HSP or EMR group. A submucosal injection was performed prior to hot snaring in the EMR group only. Complete resection was defined as the absence of neoplastic tissue from two additional biopsies of the polypectomy site. R0 resection was defined as the absence of neoplastic tissue at the margin of the resected specimen.

RESULTS

A total of 362 colon polyps from 272 patients were included, and 167 polyps in the HSP group and 155 polyps in the EMR group were analyzed. Between the polypectomy techniques, there was no significant difference in the complete resection rates, which were 96.4% (161/167) in the HSP group and 95.5% (148/155) in the EMR group (P = 0.67). The R0 resection rate in the HSP and EMR groups was significantly different, with 49.7% (83/167) and 74.8% (116/155), respectively (P < 0.001). There was no significant difference in the incidence of adverse events between the two groups.

CONCLUSIONS

The complete resection rates for small (5-10 mm) polyps were not different between HSP and EMR.

TRIAL REGISTRY

ClincialTrials.gov number NCT02239536.

Underwater versus conventional endoscopic mucosal resection for small size non-pedunculated colorectal polyps: a randomized controlled trial : (UEMR vs. CEMR for small size non-pedunculated colorectal polyps)

BACKGROUND

Underwater endoscopic mucosal resection (UEMR) is a recently developed technique and can be performed during water-aided or ordinary colonoscopy for the treatment of colorectal polyps. The objective of this clinical trial was to evaluate the efficacy and safety of UEMR in comparison with conventional endoscopic mucosal resection (CEMR) of small non-pedunculated colorectal polyps.

METHODS

Patients with small size, non-pedunculated colorectal polyps (4-9 mm in size) who underwent colonoscopic polypectomy were enrolled in this multicenter randomized controlled clinical trial. The patients were randomly allocated to two groups, an UEMR group and a CEMR group. Efficacy and safety were compared between groups.

RESULTS

In the intention-to-treat (ITT) analysis, the complete resection rate was 83.1% (59/71) in the UEMR group and 87.3% (62/71) in the CEMR group. The en-bloc resection rate was 94.4% (67/71) in the UEMR group and 91.5% (65/71) in the CEMR group (difference 2.9%; 90% CI - 4.2 to 9.9%), showed noninferiority (noninferiority margin - 5.7% < - 4.2%). No significant difference in procedure time (81 s vs. 72 s, P = 0.183) was observed. Early bleeding was observed in 1.4% of patients in the CEMR group (1/71) and 1.4% of patients in the UEMR group (1/71). None of the patients in the UEMR group complained of postprocedural bloody stool, whereas two patients in the CEMR group (2/64) reported this adverse event.

CONCLUSION

Our results indicate that UEMR is safer and just as effective as CEMR in En-bloc resection for the treatment of small colorectal polyps as such, UEMR is recommended as an alternative approach to excising small and non-pedunculated colorectal adenomatous polyps.

TRIAL REGISTRATION

Clinical Trials.gov, NCT03833492 . Retrospectively registered on February 7, 2019.

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.

Prospective randomized trial comparing the pocket-creation method and conventional method of colorectal endoscopic submucosal dissection

BACKGROUND AND AIMS

Colorectal endoscopic submucosal dissection (ESD) is recognized as a challenging procedure. Previously, we reported that a new ESD strategy using the pocket-creation method (PCM) is useful for colorectal ESD, but no prospective randomized study has evaluated the efficacy of the PCM. The aim of this study was to evaluate the efficacy and safety of PCM for colorectal ESD compared with the conventional method (CM).

METHODS

This was a prospective randomized controlled trial at 3 institutions in Japan. Patients with superficial colorectal neoplastic lesions >20 mm predicted to be intramucosal were randomly assigned to undergo ESD using the PCM or CM. Primary outcome was the ESD completion rate defined as completion of colorectal ESD with an en bloc resection using the assigned ESD method without changing to other methods or assisted by other devices.

RESULTS

We analyzed 59 patients with 59 colorectal tumors in the PCM group and 55 in the CM group. The ESD completion rate was significantly higher in the PCM group compared with the CM group (93% [55/59] vs 73% [40/55]; P  = .01). En bloc resection rates, R0 resection rates, procedure time, and dissection speed were not significantly different between the 2 groups. The incidence of adverse events was similar in the 2 groups.

CONCLUSIONS

Use of the PCM allows the endoscopist to complete the procedure with the intended method more often than the CM with similar clinical outcomes. (Clinical trial registration number: UMIN 000024394.).

Blue laser imaging and linked color imaging improve the color difference value and visibility of colorectal polyps in underwater conditions

BACKGROUND AND AIM

Underwater endoscopic mucosal resection (UEMR) has become widespread for treating colorectal polyps. However, which observational mode is best suited for determining polyp margins underwater remains unclear. To determine the best mode, we analyzed three imaging modes: white light imaging (WLI), blue laser imaging (BLI) and linked color imaging (LCI).

METHODS

Images of consecutive colorectal polyps previously examined by these three modes before UEMR were analyzed according to the degree of underwater turbidity (transparent or cloudy). Color differences between the polyps and their surroundings were calculated using the Commission Internationale d'Eclairage Lab color space in which 3-D color parameters were expressed. Eight evaluators, who were blinded to the histology, scored the visibility from one (undetectable) to four (easily detectable) in both underwater conditions. The color differences and visibility scores were compared.

RESULTS

Seventy-three polyps were evaluated. Sixty-one polyps (44 adenomatous, 17 serrated) were observed under transparent conditions, and 12 polyps (seven adenomatous, five serrated) were observed under cloudy conditions. Under transparent conditions, color differences for the BLI (8.5) and LCI (7.9) were significantly higher than that of WLI (5.7; P < 0.001). Visibility scores for BLI (3.6) and LCI (3.4) were also higher than that of WLI (3.1; P < 0.0001). Under cloudy conditions, visibility scores for LCI (2.9) and WLI (2.7) were significantly higher than that of BLI (2.2; P < 0.0001 and P = 0.04, respectively).

CONCLUSIONS

BLI and LCI were better observational modes in transparent water; however, BLI was unsuitable for cloudy conditions.

Safety and efficacy of cold snare polypectomy for pedunculated (Ip) polyps measuring less than 10 mm in diameter

BACKGROUND

Although cold snare polypectomy (CSP) has spread rapidly, it still remains controversial whether CSP is safe for pedunculated (Ip) polyps.

PURPOSE

The aim of this study was to evaluate whether CSP for Ip polyps measuring less than 10 mm in diameter might be associated with an increased rate of delayed post-polypectomy bleeding (DPPB).

METHODS

A total of 1641 colorectal polyps in 634 patients were resected at Omori Red Cross Hospital between April 2018 and December 2018. The polyps were divided into two groups depending on the morphology: the Ip group (90 polyps), and the non-Ip group (1551 polyps).

RESULTS

Among the 1641 polyps, there was no case of DPPB, including in the Ip group. Immediate bleeding occurred in a total of 101 (6.2%) cases. Polyp location in the rectum (OR (95% CI), 3.61 (1.843-7.092); p < 0.001), polyp diameter ≥ 6 mm (OR (95% CI), 2.65 (1.702-4.132); p < 0.001), Ip morphology (OR (95% CI), 15.66 (9.262-26.49); p < 0.001), and treatment with antithrombotic agents (OR (95% CI), 2.18 (1.358-3.501); p = 0.0012) were identified as significant risk factors for immediate bleeding.

CONCLUSIONS

This is the first study conducted to examine the safety of CSP for Ip polyps measuring less than 10 mm in diameter. CSP can be performed with a high level of safety even for Ip polyps. Based on our findings, we believe that Ip polyps could be included as an indication for CSP. However, prospective, randomized studies are necessary to confirm our results.

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).

An international polypectomy practice survey

Background and study aims: In recent years, cold snare polypectomy (CSP) has been recommended as the preferred approach for removal of small and diminutive colorectal polyps. We conducted an international survey among endoscopists to understand the uptake of CSP and changes in polypectomy practice during recent years.Patients and methods: Endoscopists were invited through gastroenterology, colorectal surgery and endoscopy societies to participate in an online survey. The primary outcome was to identify the predominant polypectomy approach used to remove 4‒10 mm colorectal polyps. Secondary outcomes included the uptake of CSP in the past 5 years, current polypectomy practice patterns for 1‒20 mm polyps, practice changes in recent years, and perceived benefits/concerns related to different polypectomy techniques.Results: The survey was distributed internationally by nine societies and completed by 808 endoscopists (response rate 3.7%). CSP was the predominant polypectomy technique for 4‒5 mm polyps (67.0%, 95% CI, 63.7-70.2%) and 6‒10 mm polyps (55.2%, 95% CI, 51.8-58.6%). For 1‒3 mm polyps, cold forceps remained the predominant technique (78.4%, 95% CI, 75.6-81.3%), whereas hot snare polypectomy (HSP) remained the predominant technique for 10‒20 mm polyps (92.5%, 95% CI, 90.7-94.3%). 87.5% (95% CI, 85.2-89.8%) of endoscopists reported an increase in CSP use during the past 5 years.Conclusions: This survey found a substantial increase in CSP use during recent years. CSP has become the predominant polypectomy approach for 4‒10 mm colorectal polyps, while HSP remained the predominant approach for larger (10‒20 mm) polyps. Clinical practice patterns are well aligned with recently issued guideline recommendations.

Clinical importance of cold polypectomy during the insertion phase in the left side of the colon and rectum: a multicenter randomized controlled trial (PRESECT study)

BACKGROUND AND AIMS

Colorectal polyps are often detected during the insertion phase of colonoscopy but are commonly removed during the withdrawal phase. We aimed to investigate the clinical advantages of instant removal of colorectal polyps during the insertion phase to determine the appropriate strategy for polyps detected on insertion.

METHODS

This prospective, multicenter, randomized trial targeted patients with at least 1 left-sided polyp <10 mm in size detected unintentionally on endoscope insertion from April 2018 to March 2019. Patients were allocated to the following 2 groups: study group, consisting of patients who had polyp removal instantly on insertion, and control group, comprising patients who had the endoscope inserted to the cecum first and polyps removed subsequently on withdrawal. Carbon dioxide gas insufflation and cold polypectomy were applied to minimize the influences of polypectomy on endoscope insertion. Twenty advanced endoscopists from 7 community-based institutions participated in this trial.

RESULTS

Of 1451 patients enrolled, 220 patients were eligible for full assessment. Mean total procedure time was significantly shorter in the study group (18.9 vs 22.3 minutes, P < .001). Mean pure cecal intubation time and number of polyps per patient were similar between the 2 groups. In the control group, among 107 polyps found during insertion, 48 (45.8%) required reinspection and 7 (6.5%) were completely missed, with an average reinspection time of approximately 3 minutes.

CONCLUSIONS

Polypectomy during the insertion phase in the colon and rectum significantly shortens the total procedure time and eliminates all missed polyps without experiencing any disadvantages.

Efficacy and safety of three different endoscopic methods in treatment of 6-20 mm colorectal polyps

Objective: Endoscopic resection of colorectal polyps is widely established as the optimal method to manage precancerous lesions. But the optimal technique for removal of the polyps is uncertain. The aim of this study was to compare the efficacy and safety of three methods for the management of 6-20mm colorectal polyps.Methods: A prospective, randomised controlled trial was conducted at the 900TH Hospital of Joint Logistics Support Force in Fujian, China. Endoscopically diagnosed colorectal polyps, 6-20 mm in size, were randomly assigned to the cold snare polypectomy (CSP), cold snare endoscopic mucosal resection (CS-EMR) or endoscopic mucosal resection (EMR) group. After polypectomy, additional 3-5 forceps biopsies by leading narrow-band imaging (NBI) were performed at the base and margins of polypectomy sites to assess the presence of residual polyp tissue and all samples were sent for histopathological analysis to assess completeness of resection. Polypectomy timing, tissue retrieval and complications were recorded at the time of the procedure.Results: A total of 781 polyps in 404 patients were assessed and randomly assigned to each group. Of these, 763 polyps were finally analyzed based on the pathology results. The complete resection rates with CSP, CS-EMR and EMR were 81.6%, 94.1% and 95.5%, respectively (p < .001). The intraprocedural bleeding rate, immediately after polypectomy, was significantly higher in the CSP group than in the CS-EMR and EMR group (9.4% vs. 4.4% vs. 1.9%; p < .001). However,delayed bleeding was higher in the EMR group than in the CSP and CS-EMR group (2.6% vs. 1.2% vs. 0.8%, respectively; p = .215). In the multivariate analysis showed that the operation method, lesion size, morphology and the number of resection were independent risk factors for complete resection rate (CRR) (p < .05), but the location and pathological classification of polyps had no significant influence on CRR.Conclusions: CS-EMR is safe and effective in the treatment of 6-20 mm colorectal polyps. Especially for 6-15 mm non-pedunculated polyps, CS-EMR has a high histological complete resection rate comparable to EMR, and retains the low risk of delayed complications after polypectomy with cold snare. CS-EMR is expected to become a more valuable new cold-cutting technique after cold snare polypectomy.

Antiplatelets, anticoagulants, and colonoscopic polypectomy

The management of antiplatelet and anticoagulant (ie, antithrombotic) agents is challenging in the periendoscopic setting. In this state-of-the-art update, we review current best practice recommendations focusing on the risk of immediate and delayed postpolypectomy bleeding in the context of drug discontinuation (ie, temporary interruption) and drug continuation. The data regarding polypectomy technique (cold snare vs conventional thermal-based) and prophylactic placement of hemostatic clips are evaluated to assess whether these endoscopic techniques are beneficial in reducing postpolypectomy bleeding. Finally, clinical takeaways are provided to facilitate safer polypectomy among patients on antiplatelet and anticoagulant agents.

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.

Idiopathic Ileocolonic Varices Coexisting with a Colon Polyp Treated Successfully by Endoscopy: A Case Report and Literature Review

Colonic varices are usually associated with portal hypertension. Idiopathic colonic varices are extremely rare. A 68-year-old man with a positive fecal occult blood test result underwent colonoscopy. We detected idiopathic ileocolonic varices and a coexisting ascending colon polyp. While reviewing the literature, we found cases of biopsies and polypectomies resulting in significant bleeding. We herein report a case of idiopathic ileocolonic varices coexisting with a colon polyp treated successfully by endoscopy. The coexistence of colonic varices and a colorectal lesion that requires endoscopic treatment may lead to significant bleeding. During management, the development of a treatment strategy and obtaining informed consent are necessary.

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.

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.

Lesion Retrieval, Specimen Handling, and Endoscopic Marking in Colonoscopy

Retrieval of lesions after endoscopic polypectomy enables histopathologic analysis and guides future surgical management and endoscopic surveillance intervals. Various techniques and devices have been described with distinct advantages and disadvantages to accomplish retrieval. Appropriate histopathologic analysis depends on lesion handling and preparation. How lesions are handled further depends on size, endoscopic appearance, and removal technique. Endoscopic marking or tattooing is a well-described process that uses dye mediums to leave longstanding marks in the colon. Techniques, dye mediums, and locations within the colon influence tattoo approach.

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.

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.

Endoscopic Management of Post-Polypectomy Bleeding

Post-polypectomy bleeding (PPB) is one of the most common complications of endoscopic polypectomy. There are multiple risk factors related to patient and polyp characteristics that should be considered. In most cases, immediate PPB can be effectively managed endoscopically when recognized and managed promptly. Delayed PPB can manifest in a myriad of ways. In severe delayed PPB, resuscitation for hemodynamic stabilization should be prioritized, followed by endoscopic evaluation and therapy once the patient is stabilized. Future areas of research in PPB include the risks of direct oral anticoagulants and of specific electrosurgical settings for hot-snare polypectomy vs. cold-snare polypectomy, benefits of closure of post-polypectomy mucosal defects using through-the-scope clips, and prospective comparative evaluation of newer hemostasis agents such as hemostatic spray powder and over-the-scope clips.

Continuous Anticoagulation and Cold Snare Polypectomy Versus Heparin Bridging and Hot Snare Polypectomy in Patients on Anticoagulants With Subcentimeter Polyps: A Randomized Controlled Trial

BACKGROUND

Management of anticoagulants for patients undergoing polypectomy is still controversial. Cold snare polypectomy (CSP) is reported to cause less bleeding than hot snare polypectomy (HSP).

OBJECTIVE

To compare outcomes between continuous administration of anticoagulants (CA) with CSP (CA+CSP) and periprocedural heparin bridging (HB) with HSP (HB+HSP) for subcentimeter colorectal polyps.

DESIGN

Multicenter, parallel, noninferiority randomized controlled trial. (University Hospital Medical Information Network Clinical Trials Registry: UMIN000019355).

SETTING

30 Japanese institutions.

PATIENTS

Patients receiving anticoagulant therapy (warfarin or direct oral anticoagulants) who had at least 1 nonpedunculated subcentimeter colorectal polyp.

INTERVENTION

Patients were randomly assigned to undergo HB+HSP or CA+CSP and followed up 28 days after polypectomy.

MEASUREMENTS

The primary end point was incidence of polypectomy-related major bleeding (based on the incidence of poorly controlled intraprocedural bleeding or postpolypectomy bleeding requiring endoscopic hemostasis). The prespecified inferiority margin was -5% (CA+CSP vs. HB+HSP).

RESULTS

A total of 184 patients were enrolled: 90 in the HB+HSP group, 92 in the CA+CSP group, and 2 who declined to participate after enrollment. The incidence of polypectomy-related major bleeding in the HB+HSP and CA+CSP groups was 12.0% (95% CI, 5.0% to 19.1%) and 4.7% (CI, 0.2% to 9.2%), respectively. The intergroup difference for the primary end point was +7.3% (CI, -1.0% to 15.7%), with a 0.4% lower limit of 2-sided 90% CI, demonstrating the noninferiority of CA+CSP. The mean procedure time for each polyp and the hospitalization period were longer in the HB+HSP than in the CA+CSP group.

LIMITATION

An open-label trial assessing 2 factors (anticoagulation approach and polypectomy procedure type) simultaneously.

CONCLUSION

Patients having CA+CSP for subcentimeter colorectal polyps who were receiving oral anticoagulants did not have an increased incidence of polypectomy-related major bleeding, and procedure time and hospitalization were shorter than in those having HB+HSP.

PRIMARY FUNDING SOURCE

Japanese Gastroenterological Association.

Comparison of Underwater vs Conventional Endoscopic Mucosal Resection of Intermediate-Size Colorectal Polyps

BACKGROUND & AIMS

Endoscopic mucosal resection (EMR) with submucosal injection is an established method for removing colorectal polyps, although the en bloc resection rate decreases when polyp size exceeds 10 mm. Piecemeal resection increases local recurrence. Underwater EMR (UEMR) is an effective technique for removal of sessile colorectal polyps and we investigated whether it is superior to conventional EMR (CEMR).

METHODS

We conducted a multicenter randomized controlled trial at 5 institutions in Japan. Patients with endoscopically diagnosed, intermediate-size (10-20 mm) sessile colorectal lesions were randomly assigned to undergo UEMR or CEMR. Only the most proximal lesion was registered. The UEMR procedure included immersion of the entire lumen in water and snare resection of the lesion without submucosal injection of normal saline. We analyzed outcomes of 108 colorectal lesions in the UEMR group and 102 lesions in the CEMR group. R0 resection was defined as en bloc resection with a histologically confirmed negative resection margin. The primary endpoint was the difference in the R0 resection rates between groups.

RESULTS

The proportions of R0 resections were 69% (95% confidence interval [CI] 59%-77%) in the UEMR group vs 50% (95% CI 40%-60%) in the CEMR group (P = .011). The proportions of en bloc resections were 89% (95% CI 81%-94%) in the UEMR group vs 75% (95% CI 65%-83%) in the CEMR group (P = .007). There was no significant difference in median procedure time (165 vs 175 seconds) or proportions of patients with adverse events (2.8% in the UEMR group vs 2.0% in the CEMR group).

CONCLUSIONS

In a multicenter randomized controlled trial, we found that UEMR significantly increased the proportions of R0 resections for 10- to 20-mm sessile colorectal lesions without increasing adverse events or procedure time. Use of this procedure should be encouraged. Trials registry number: UMIN000018989.

Cold snare polypectomy: Indications, devices, techniques, outcomes and future

Colonoscopy has been shown to reduce the risk of colon cancer by enabling the removal of precancerous lesions. Although cold snare and hot snare polypectomy have similar retrieval rates and complete resection rates, rates of delayed bleeding tend to be lower with cold snare polypectomy than with hot snare polypectomy, especially for patients taking antithrombotic agents. However, among cold snares there may be differences in terms of the completeness of polyp excision, as complete removal appears more likely with thin-wire dedicated cold snares compared to the traditional, thick-wire cold snares. Cold snare polypectomy may be especially well suited for use in patients taking antithrombotic agents, due to its minimal risk of delayed bleeding. Histological analyses suggest that cold snare polypectomy causes less damage to blood vessels in the submucosal layers, which results in a reduced incidence of hemorrhage compared to hot snare polypectomy. However, cold snare removal of small polyps may result in fragmentation of small specimens during collection and concerns as to whether the resection is complete. An endoscopy biomarker of effective cold snare polypectomy technique is needed to ensure complete removal of non-pedunculated colorectal polyps ≤10 mm. Future uses of cold snare polypectomy may include piecemeal removal of sessile serrated adenoma/polyp lesions >10 mm. Currently, cold snare polypectomy should be considered a primary method for colorectal polyps of less than 10 mm, especially those in the 4- to 10-mm range.

Hot snare vs. cold snare polypectomy for endoscopic removal of 4 - 10 mm colorectal polyps during colonoscopy: a systematic review and meta-analysis of randomized controlled studies

Introduction  In recent years, cold snare polypectomy (CSP) has increasingly been used over hot snare polypectomy (HSP) for the removal of colorectal polyps (4 - 10 mm in size). However, the optimal technique (CSP vs. HSP), in terms of complete polyp resection and complications, is uncertain. Our aim was to compare incomplete resection rate (IRR) of polyps and complications using CSP vs. HSP. Methods  Randomized controlled studies (RCTs) comparing CSP and HSP for removal of 4 - 10 mm colorectal polyps were considered. Studies were included in the analysis if they obtained biopsy specimens from the resection margin to confirm the absence of residual tissue and reported complications. IRR and complication rate were the outcome measures. Pooled rates were reported as Odds Ratios (OR) or risk difference with 95 % Confidence Interval (CI). Results  In total, three RCTs were included in the final analysis. A total of 1051 patients with 1485 polyps were randomized to either HSP group (n = 741 polyps) or CSP group (n = 744 polyps). The overall IRR did not differ between the two groups (HSP vs. CSP: 2.4 % vs. 4.7 %; OR 0.51, 95 %CI 0.13 - 1.99, P  = 0.33, I 2  = 73 %). The HSP group had a lower rate of overall complications compared to the CSP group (3.7 % vs. 6.6 %; OR 0.53, 95 % CI 0.3 - 0.94, P  = 0.03, I 2  = 0 %). Polyp retrieval rates were not different between the two groups (99 % vs. 98.1 %). Conclusion  Our results suggest that HSP and CSP techniques can be effectively used for the complete removal of 4 - 10 mm colorectal polyps; however, HSP has a lower incidence of overall complications.

Resection rates and safety profile of cold vs. hot snare polypectomy in polyps sized 5-10 mm and 11-20 mm

BACKGROUND AND AIMS

Hot snare (HS) is widely used for the resection of adenomas >5 mm. The cold snare (CS) has a better safety profile and is more cost-effective. The aims of this study were to evaluate effectiveness and safety of CS polypectomy (CSP) compared to HS polypectomy (HSP) for adenomas sized 5-10 mm and 11-20 mm.

METHODS

4018 colonoscopies performed within "quality certificate for screening colonoscopy" with one polypectomy of an adenoma sized 5-20 mm each were included. Retrieval rates, complete resection rates and complication rates were assessed and compared between CSP and HSP for adenomas sized 5-10 mm and 11-20 mm. Histologic subgroups were additionally assessed.

RESULTS

Complete resection rates (5-10 mm: CSP: 89.4% vs. HSP: 87.9%, p = 0.33; 11-20 mm: CSP: 81.8% vs. 80.9%; p = 1), retrieval rates (5-10 mm: CSP: 99.5% vs. HSP: 99.4%, p = 0.76; 11-20 mm: CSP: 100% vs. HSP: 99%, p = 1) and complication rates (5-10 mm: CSP: 0.2% vs. HSP: 0.2%; p = 1; 11-20 mm: CSP: 0% vs. HSP: 1%, p = 1) were equal between CSP and HSP for adenomas sized 5-10 mm as well as 11-20 mm. For serrated adenomas sized 5-10 mm, HSP was superior to CSP (88.7% vs. 77.2%, p < 0.05) regarding the complete resection rate, but not for advanced adenomas (HSP: 89.1% vs. 87.3%, p = 0.69) or adenomas with high-grade dysplasia (HSP: 76.7% vs. 75%, p = 1).

CONCLUSION

This study further supports the use of CSP for polyps sized 5-10 mm and additionally suggests also using CSP for polyps sized 11-20 mm. These findings, as well as the best method for resection of serrated polyps should be validated in further studies.

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.

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.

Usefulness of close observation with non-magnified blue laser imaging for determining cold polypectomy indications

PURPOSE

To examine the usefulness of non-magnified close observation with blue laser imaging (BLI) using a colonoscope with close observation capability in determining indications for cold polypectomy.

METHODS

We conducted an image evaluation study on 100 consecutive colorectal lesions of 10 mm or less which were observed endoscopically without magnification using BLI mode prior to treatment. Two experts and two non-experts reviewed the images using the Japan NBI expert team (JNET) classification and the diagnostic accuracy was analyzed.

RESULTS

The final pathological diagnoses of the 100 lesions were hyperplastic/sessile serrated polyp (HP/SSP), low grade dysplasia (LGD), high grade dysplasia (HGD) and deep submucosal invasive cancer (dSM), respectively, in 12, 79, 9 and 0 lesions. When JNET classification type 1 corresponds to HP/SSP; 2A to LGD; 2B to HGD; and 3 to dSM; the overall diagnostic accuracy was 84.3%. Accuracy was 90.5% for experts and 78.0% for non-experts. High confidence rate was 67.5% for experts and 48.0% for non-experts. In diagnostic accuracy for HGD, the sensitivity, specificity, PPV and NPV were, respectively, 77.8%, 98.9%, 87.5% and 97.8% for experts; and 66.6%, 92.3%, 46.2% and 96.6% for non-experts.

CONCLUSIONS

The diagnostic accuracy of unmagnified close observation with BLI using a colonoscope with close observation capability is similar to that reported for magnifying endoscopy and is useful in predicting the histological diagnosis of colorectal polyps of 10 mm or less although the effectiveness may be limited for non-experts. This modality is a potentially useful tool in deciding indications for cold polypectomy.

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.

Feasibility of Underwater Endoscopic Mucosal Resection for Colorectal Lesions: A Single Center Study in Japan

Background

Underwater endoscopic mucosal resection (U-EMR) has emerged as an alternative technique for the resection of colorectal lesions. This study aimed to evaluate our initial experience using U-EMR.

Methods

This is a single-center, retrospective case series study. We analyzed the clinical outcomes of consecutive patients who underwent U-EMR in our endoscopy center, from December 2015 to February 2017.

Results

Our analysis included 64 lesions, contributed by 38 patients, with a mean age of 68.6 years (range, 25 to 90 years). The study sample included 33 right-sided and 25 left-sided colon lesions, and seven rectal lesions, with an average size of 16.2 mm (6 - 40 mm). Of these, 46 lesions were polypoid and 18 ones non-polypoid. Histologically, 31 lesions were low-grade adenomas, eight ones were high-grade adenomas, 11 were mucosal cancers, four were submucosal cancers, and 10 were classified as “others”. En bloc resection was achieved in 52 (81%) lesions, with an en bloc resection rate of 95% for lesions < 20 mm and 55% for lesions ≥ 20 mm. Complete resection of neoplastic epithelial lesions, defined by a negative pathological margin, was achieved in 32 of 59 neoplastic epithelial lesions (54%). We identified three cases (5%) of post-procedural bleeding and one case of perforation (2%).

Conclusions

U-EMR can be feasibly used for resection of colonic lesions, including lesions ≥ 20 mm, although the en bloc resection rate for these lesions was lower than for lesions < 20 mm.