TECHNICAL REVIEW Colonic polypectomy (with videos) Nicholas G. Burgess, MBChB, BSc, FRACP, Farzan F. Bahin, MBBS, FRACP, Michael J. Bourke, MBBS, FRACP Sydney, New South Wales, Australia The role of colonoscopic polypectomy in the prevention of were searched for English-language manuscripts by using colorectal cancer is now well-established. Resection of adeno- the keywords “colonoscopy” AND “colon OR colonic OR matous colonic polyps reduces colorectal cancer incidence1 colorectal” AND “polypORneoplasmORneoplasia” AND and mortality.2 Despite this proven effectiveness, polyp “polypectomy OR resection.” Studies were included for resection techniques and outcomes remain understudied, review if they were well-designed, prospective trials or and the potential for improvement in efficacy and safety is systematic reviews. Where these were not available, high. Advances in endoscopic and electrosurgical evidence was assessed from large, prospective, observa- technology have allowed the role of endoscopic resection tional trials and case series or reports from recognized to expand, reducing the reliance on surgery for early cancer experts. Each study was assessed according to the and larger or more complex lesions. The optimum GRADE guidelines (Table 1.), and, where sufficient resection technique for any given polyp is quick, ensures evidence was available, a recommendation was made complete adenoma removal, and minimizes adverse events. based on an overall review of the strength of the Variations in polyp size, morphology, histology, and evidence.3 Two reviewers independently reviewed the location mean that there cannot be a “one-size-fits-all” available evidence for each practice point, then arrived approach to resection technique and that polypectomy at a consensus agreement. Each section of the review must be tailored to the characteristics of the lesion, based contains a summary box of the key findings, an on the best available evidence. This review will focus on the indication of the strength of the evidence supporting technical aspects of endoscopic resection in the colon, that finding, and an indication of whether the highlight areas in which evidence is lacking, and comment statement is strong or weak, based on the available on future directions in research. evidence. Existing guidelines were reviewed by searching the National Guideline Clearinghouse for GRADING OF EVIDENCE evidence, specifically on the technical aspects of colon polyp resection. Polyp surveillance strategies and the In conducting this review, electronic databases, associated evidence are beyond the scope of this including MEDLINE/PubMed and the Cochrane Library, review. Before-resection endoscopic assessment of the target lesion is a pivotal component of polypectomy Abbreviations: APC, argon plasma coagulation; ASGE, American Society practice but is covered extensively elsewhere so is not for Gastrointestinal Endoscopy; CT, Computed tomography; DP, dimin- 4 utive polyp; EMR, Endoscopic mucosal resection; ESD, endoscopic sub- addressed in this review. Polypectomy is a technical mucosal dissection; EUS, Endoscopic ultrasound; PRR, polyp retrieval skill, so there are several aspects that are difficult to rate; SC-1, first surveillance colonoscopy; SC-2, second surveillance colo- objectively study. There is increasing evidence that noscopy; SSP, sessile serrated polyp. technique has a strong influence on polypectomy DISCLOSURE: N. Burgess was supported by a grant from the Westmead outcomes. As a result, we have provided technical tips Medical Research Foundation. F. Bahin was supported by a grant from to guide endoscopists on achieving efficient and safe the National Health and Medical Research Council of Australia. Neither excision of lesions. These are not primarily evidence entity influenced preparation, review, or approval of the manuscript. All based but are derived from the literature and our own other authors disclosed no financial relationships relevant to this article. experience, observation, and insights into the understanding of best-practice polypectomy. This video can be viewed directly A total of 2547 articles were identified by using from the GIE website or by using the search strategy. Titles were initially screened, the QR code and your mobile de- and 630 articles were deemed relevant for review. vice. Download a free QR code Article abstracts were individually evaluated for inclusion. scanner by searching “QR Scanner” A total of 410 were excluded.Thecompletetextsof in your mobile device’s app store. the remaining 220 were obtained for the articles that Copyright ª 2015 by the American Society for Gastrointestinal Endoscopy were deemed potentially relevant. In addition, a manual 0016-5107/$36.00 recursive search of the reference sections of the http://dx.doi.org/10.1016/j.gie.2014.12.027 selected studies was performed to identify other www.giejournal.org Volume 81, No. 4 : 2015 GASTROINTESTINAL ENDOSCOPY 813 Colonic polypectomy Burgess et al TABLE 1. GRADE system for rating the quality of evidence for effectiveness of complete resection for this type of guidelines3 forceps. Hot biopsy forceps techniques may provide an advan- Quality of tage over cold biopsy forceps polypectomy because of evidence Definition Symbol the penumbra of thermal ablation created beyond the High quality Further research is very unlikely to change 4444 focus of tissue excision. However, rates of incomplete our confidence in the estimate of effect. resection range from 17% to 22%,12,13 and the thermal ef- Moderate Further research is likely to have an 444B fect results in difficulty with histologic interpretation of quality important impact on our confidence in the the resected specimen.14-17 It is recommended that hot estimate of effect and may change the estimate. biopsy forceps are used with a low power, peak voltage limited current, and thought that brief application may Low quality Further research is very likely to have an 44BB important impact on our confidence in reduce thermal injury; however, in practice the majority the estimate of effect and is likely to of studies are performed with a coagulating current, change the estimate. and application time inherently varies.18,19 Considerable Very low Any estimate of effect is very uncertain. 4BBB lateral and deep thermal injury can occur with hot biopsy quality forceps. An in vivo porcine study showed that residual target tissue beneath the hot biopsy forceps ulcer occurred in 15%, lateral mucosal injury was unpredict- able, and transmural injury occurred in nearly a third of potentially relevant articles. The full manuscripts of cases.15 Observational studies have demonstrated a high thesearticleswerereviewedindetailtopreparea delayed bleeding rate associated with hot biopsy standardized evidence table and generate focused forceps use.19,20 A survey of hot biopsy forceps use by recommendations. U.S. endoscopists in 13,081 procedures suggested high rates of delayed bleeding (0.41%) and perforation (0.05%), particularly in the right side of the colon.21 REMOVAL OF DIMINUTIVE AND SMALL Unquestionably, removal of DPs should be safe. POLYPS Because of its ineffectiveness and high adverse event rates, hot biopsy forceps cannot be recommended for Diminutive polyps (DP) are defined as polyps %5mm removal of DPs. in size and are extremely common, occurring in 60% to Cold-snare polypectomy has emerged in recent years 70% of patients undergoing screening or surveillance colo- as a safe and efficient way to remove diminutive and noscopy.5 They have a low prevalence of advanced small (%9 mm) polyps, with lower rates of incomplete histologic features.5,6 Although resection of DPs by using resection than biopsy techniques22 and few adverse cold biopsy forceps is attractive, based on ease, accessi- events.23-25 The excision should include a 1- to 2–mm bility, and safety, this method has been associated with sig- rim around the polyp to ensure complete removal nificant rates of incomplete resection. Complete resection (Videos 1 and 2; available online at www.giejournal. by cold biopsy forceps occurred in only 39% when the ad- org). Intraprocedural bleeding is common; however, equacy of resection was assessed by performing EMR of this is typically self-limited and does not result in clini- the polypectomy site.7 Another study examined the DP cally significant bleeding even in anticoagulated pa- cold biopsy forceps site at endoscopy 1 to 4 weeks after tients.26 Cold-snare polypectomy is safe for lesions up the index resection. Residual adenoma was present in to 9 mm in size, with negligible rates of bleeding.23 29%.8 In contrast to this, a similar recent study has Cold-snare polypectomy of lesions O6mminsizeis shown that when performed in conjunction with associated with a residual protrusion in the center of chromoendoscopy and with careful washing and post- the defect (Fig. 1). This is not associated with short- resection examination, complete resection was achieved term sequelae; however, the protrusion may contain in 90% of DPs and 100% of polyps !3 mm in size.9 The muscularis mucosa, indicating incomplete mucosal key concern regarding cold biopsy forceps is that a resection. This aspect requires further research. Early number of bites may be required to remove the polyp, follow-up should be considered when the polyp contains and immediate bleeding and traumatic disruption of the high-grade dysplasia.27 A2003surveyofU.S. mucosal surface may interfere with the assessment of endoscopists showed that 80% used hot snare the adequacy of resection