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Have We Defined Best Colonoscopic Polypectomy Practice in the United States?

2007; Elsevier BV; Volume: 5; Issue: 6 Linguagem: Inglês

10.1016/j.cgh.2007.03.027

1542-7714

Douglas K. Rex,

Esophageal Cancer Research and Treatment

In this issue, Fujishiro et al1Fujishiro M. et al.Outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms obtained in 200 consecutive cases.Clin Gastroenterol Hepatol. 2007; 5: 678-683Abstract Full Text Full Text PDF PubMed Scopus (309) Google Scholar report their experience with endoscopic submucosal dissection (ESD) of 200 large colorectal polyps. ESD was developed in Japan to improve the curative endoscopic resection of early gastric neoplasms, and ESD has recently been extended to the rectum and colon. The technical skills involved in ESD, which have been demonstrated on video at a number of North American meetings, are impressive and leave American endoscopists humbled and with a familiar sense of inferiority with respect to our Japanese colleagues. The technique starts with submucosal injection of a long-acting solution, followed by circumferential incision into the submucosa around the perimeter of the lesion, followed by submucosal dissection until the polyp is delivered, in one piece (en bloc resection) if possible. There were 12 perforations (6%) in the series, but only 1 required surgical resection. Patients were observed post-ESD in the hospital and discharged within 1 week. The recurrence rate at follow-up was only 1.8% and was 0% among the nearly 90% of patients with successful en bloc resection. There are excellent recent summaries of ESD technique2Kodashima S. Fujishiro M. Yahagi N. et al.Endoscopic submucosal dissection using flexknife.J Clin Gastroenterol. 2006; 40: 378-384Crossref PubMed Scopus (65) Google Scholar and commentaries on ESD3Das A. Endoscopic submucosal dissection: cure in one piece.Endoscopy. 2006; 38: 1044-1046Crossref PubMed Scopus (10) Google Scholar available.What is the rationale for ESD? First, the initial cure rate with ESD is much higher than that of traditional piecemeal polypectomy. Piecemeal technique has a failure rate at first follow-up that ranges from 14%–55%.4Binmoeller K.F. Bohnacker S. Seifert H. et al.Endoscopic snare excision of "giant" colorectal polyps.Gastrointest Endosc. 1996; 43: 183-188Abstract Full Text Full Text PDF PubMed Scopus (193) Google Scholar, 5Zlatanic J. Waye J.D. Kim P.S. et al.Large sessile colonic adenomas: use of argon plasma coagulator to supplement piecemeal snare polypectomy.Gastrointest Endosc. 1999; 49: 731-735Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 6Church J.M. Experience in the endoscopic management of large colonic polyps.ANZ J Surg. 2003; 73: 988-995Crossref PubMed Scopus (86) Google Scholar, 7Brooker J.C. Saunders B.P. Shah S.G. et al.Endoscopic resection of large sessile colonic polyps by specialist and non-specialist endoscopists.Br J Surg. 2002; 89: 1020-1024Crossref PubMed Scopus (72) Google Scholar, 8Doniec J.M. Lohnert M.S. Schniewind B. et al.Endoscopic removal of large colorectal polyps: prevention of unnecessary surgery?.Dis Colon Rectum. 2003; 46: 340-348Crossref PubMed Scopus (131) Google Scholar, 9Walsh R.M. Ackroyd F.W. Shellito P.C. Endoscopic resection of large sessile colorectal polyps.Gastrointest Endosc. 1992; 38: 303-309Abstract Full Text PDF PubMed Scopus (191) Google Scholar, 10Iishi H. Tatsuta M. Iseki K. et al.Endoscopic piecemeal resection with submucosal saline injection of large sessile colorectal polyps.Gastrointest Endosc. 2000; 51: 697-700Abstract Full Text Full Text PDF PubMed Scopus (143) Google Scholar, 11Conio M. Repici A. Demarquay J.F. et al.EMR of large sessile colorectal polyps.Gastrointest Endosc. 2004; 60: 234-241Abstract Full Text Full Text PDF PubMed Scopus (187) Google Scholar, 12Regula J. Wronska E. Polkowski M. et al.Argon plasma coagulation after piecemeal polypectomy of sessile colorectal adenomas: long-term follow-up study.Endoscopy. 2003; 35: 212-218Crossref PubMed Scopus (127) Google Scholar, 13Higaki S. Hashimoto S. Harada K. et al.Long-term follow-up of large flat colorectal tumors resected endoscopically.Endoscopy. 2003; 35: 845-849Crossref PubMed Scopus (109) Google Scholar, 14Bories E. Pesenti C. Monges G. et al.Endoscopic mucosal resection for advanced sessile adenoma and early-stage colorectal carcinoma.Endoscopy. 2006; 38: 231-235Crossref PubMed Scopus (71) Google Scholar These failures probably result from the inability to fully snare resect very flat portions that are present in many large sessile polyps, and survival of clusters of dysplastic cells in the flat portions and at the margin of the polyp and at the borders of resected pieces. Effective ablation of these flat areas and the polyp edges reduces the chance of residual polyp at first follow-up15Brooker J.C. Saunders B.P. Shah S.G. et al.Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations.Gastrointest Endosc. 2002; 55: 371-375Abstract Full Text Full Text PDF PubMed Scopus (251) Google Scholar but is still less effective than ESD. Second, ESD greatly improves the quality of the pathologic specimen, allowing greater assurance that the lateral and deep margins are free of neoplasia.Despite these advantages, ESD has limitations that will slow or prevent its spread to the United States in the near future (Table 1). First, in its current form it is not an efficient method of removing polyps. Although Fujishiro et al1Fujishiro M. et al.Outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms obtained in 200 consecutive cases.Clin Gastroenterol Hepatol. 2007; 5: 678-683Abstract Full Text Full Text PDF PubMed Scopus (309) Google Scholar did not describe times to complete ESD, resection times of 3–5 hours have been reported for performance of ESD in the stomach or colon.16Shimura T. Sasaki M. Kataoka H. et al.Advantages of endoscopic submucosal dissection over conventional endoscopic mucosal resection.J Gastroenterol Hepatol. 2006; (published online July 18:1-6.)Google Scholar, 17Fujishiro M. Yahagi N. Kakushima N. et al.Successful endoscopic en bloc resection of a large laterally spreading tumor in the rectosigmoid junction by endoscopic submucosal dissection.Gastrointest Endosc. 2006; 63: 178-183Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar Piecemeal polypectomy of large sessile polyps, which requires procedure times about 2-fold to 2.5-fold longer than colonoscopy with removal of small polyps,18Overhiser A. Rex D.K. Resources required for resection of large sessile colon polyps.Gastrointest Endosc. 2006; 63: AB202Abstract Full Text Full Text PDF Google Scholar is anecdotally considered to be too inefficient (and too dangerous) by many American endoscopists, and many endoscopically resectable polyps in the United States are being sent for surgical resection.19Onken J.E. Friedman J.Y. Subramanian S. et al.Treatment patterns and costs associated with sessile colorectal polyps.Am J Gastroenterol. 2002; 97: 2896-2901Crossref PubMed Scopus (40) Google Scholar From a practice perspective, spending multiple hours on endoscopic resection of a polyp is unlikely to be accepted on any significant scale in the United States without substantial adjustment in reimbursement. If ESD becomes efficient, training American endoscopists in ESD (or a subset of endoscopists at referral centers) will be an obstacle if it remains as technically demanding as it is currently. Other obstacles to ESD in the United States are the high perforation rates of ESD and teaching American endoscopists to recognize small perforations and close them with clips.20Heldwein W. Dollhopf M. Rosch T. et al.The Munich Polypectomy Study (MUPS): prospective analysis of complications and risk factors in 4000 colonic snare polypectomies.Endoscopy. 2005; 37: 1116-1122Crossref PubMed Scopus (288) Google Scholar, 21Taku K. Sano Y. Fu K.I. et al.Iatrogenic perforation at therapeutic colonoscopy: should the endoscopist attempt closure using endoclips or transfer immediately to surgery?.Endoscopy. 2006; 38: 428Crossref PubMed Scopus (38) Google Scholar, 22Fujishiro M. Yahagi N. Kakushima N. et al.Successful nonsurgical management of perforation complicating endoscopic submucosal dissection of gastrointestinal epithelial neoplasms.Endoscopy. 2006; 38: 1001-1006Crossref PubMed Scopus (157) Google Scholar Fear of perforation might be greater in the United States because the medicolegal environment is different (worse) than in Japan, and because even complex polypectomy in the United States is typically an outpatient procedure. ESD is a powerful concept, however, and development of easy-to-use, safe, and efficient systems to perform ESD should be a priority for endoscope and accessory manufacturers and endoscopic investigators. When ESD technique is more fully developed, it would help to conduct randomized comparisons of ESD with piecemeal polypectomy, particularly if ESD remains so time-consuming, focused on whether the long-term outcomes and costs of ESD and piecemeal polypectomy are substantially different.Table 1Piecemeal Polypectomy Versus Endoscopic Submucosal Dissection of Large Sessile Colorectal PolypsPiecemeal polypectomyESDEfficiencyFairPoorEffectivenessGoodExcellentQuality of pathology specimenInherently problematicExcellentPerforation riskAbout 1%About 5% Open table in a new tab If we accept the suggestion that ESD is not ready for prime time in the United States, where does that leave colonoscopic polypectomy practice in our country? Should we be satisfied with our current polypectomy practices? Is this an important topic that deserves increased attention, study, and resources? How much do polypectomy techniques vary between endoscopists, and do different techniques result in substantially different outcomes?Our main technical goals in colonoscopic polypectomy are effective eradication of polyps, minimal complications, and efficiency in completion of polypectomy and retrieval of specimens. In the United States, it has been estimated that more than 14 million colonoscopies per year are performed,23Seeff L.C. Richards T.B. Shapiro J.A. et al.How many endoscopies are performed for colorectal cancer screening? results from CDC's survey of endoscopic capacity.Gastroenterology. 2004; 127: 1670-1677Abstract Full Text Full Text PDF PubMed Scopus (365) Google Scholar of which a substantial fraction (for careful colonoscopists more than half)24Barclay R. Vicari J.J. Johanson J.F. et al.Effect of a pre-specified minimum colonoscopic withdrawal time on adenoma detection rates during screening colonoscopy.Gastrointest Endosc. 2006; 63: AB83Google Scholar include 1 or more polypectomies. Polypectomy is the means of preventing colorectal cancer during colonoscopy25Winawer S.J. Zauber A.G. Ho M.N. et al.Prevention of colorectal cancer by colonoscopic polypectomy: the National Polyp Study Workgroup.N Engl J Med. 1993; 329: 1977-1981Crossref PubMed Scopus (3862) Google Scholar, 26Citarda F. Tomaselli G. Capocaccia R. et al.Efficacy in standard clinical practice of colonoscopic polypectomy in reducing colorectal cancer incidence.Gut. 2001; 48: 812-815Crossref PubMed Scopus (611) Google Scholar and is the most important therapeutic procedure in gastrointestinal medicine. The National Polyp Study estimated that polypectomy prevented 76%–90% of incident colorectal cancers,25Winawer S.J. Zauber A.G. Ho M.N. et al.Prevention of colorectal cancer by colonoscopic polypectomy: the National Polyp Study Workgroup.N Engl J Med. 1993; 329: 1977-1981Crossref PubMed Scopus (3862) Google Scholar suggesting that our current polypectomy techniques are quite effective. On the other hand, U.S. dietary intervention27Schatzkin A. Lanza E. Corle D. et al.Lack of effect of a low-fat, high-fiber diet on the recurrence of colorectal adenomas: Polyp Prevention Trial Study Group.N Engl J Med. 2000; 342: 1149-1155Crossref PubMed Scopus (827) Google Scholar, 28Alberts D.S. Martinez M.E. Roe D.J. et al.Lack of effect of a high-fiber cereal supplement on the recurrence of colorectal adenomas: Phoenix Colon Cancer Prevention Physicians' Network.N Engl J Med. 2000; 342: 1156-1162Crossref PubMed Scopus (725) Google Scholar and chemoprevention29Robertson D.J. Greenberg E.R. Beach M. et al.Colorectal cancer in patients under close colonoscopic surveillance.Gastroenterology. 2005; 129: 34-41Abstract Full Text Full Text PDF PubMed Scopus (388) Google Scholar studies showed a much lower preventive effect against colorectal cancer by colonoscopy and polypectomy. Two studies have suggested that more than 25% of cancers that develop after colonoscopy might result from ineffective polypectomy.30Pabby A. Schoen R.E. Weissfeld J.L. et al.Analysis of colorectal cancer occurrence during surveillance colonoscopy in the dietary Polyp Prevention Trial.Gastrointest Endosc. 2005; 61: 385-391Abstract Full Text Full Text PDF PubMed Scopus (312) Google Scholar, 31Farrar W.D. Sawhney M.S. Nelson D.B. et al.Colorectal cancers found after a complete colonoscopy.Clin Gastroenterol Hepatol. 2006; 4: 1259-1264Abstract Full Text Full Text PDF PubMed Scopus (260) Google Scholar This and the widely variable success rates of eradication of large sessile polyps with piecemeal technique,4Binmoeller K.F. Bohnacker S. Seifert H. et al.Endoscopic snare excision of "giant" colorectal polyps.Gastrointest Endosc. 1996; 43: 183-188Abstract Full Text Full Text PDF PubMed Scopus (193) Google Scholar, 5Zlatanic J. Waye J.D. Kim P.S. et al.Large sessile colonic adenomas: use of argon plasma coagulator to supplement piecemeal snare polypectomy.Gastrointest Endosc. 1999; 49: 731-735Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 6Church J.M. Experience in the endoscopic management of large colonic polyps.ANZ J Surg. 2003; 73: 988-995Crossref PubMed Scopus (86) Google Scholar, 7Brooker J.C. Saunders B.P. Shah S.G. et al.Endoscopic resection of large sessile colonic polyps by specialist and non-specialist endoscopists.Br J Surg. 2002; 89: 1020-1024Crossref PubMed Scopus (72) Google Scholar, 8Doniec J.M. Lohnert M.S. Schniewind B. et al.Endoscopic removal of large colorectal polyps: prevention of unnecessary surgery?.Dis Colon Rectum. 2003; 46: 340-348Crossref PubMed Scopus (131) Google Scholar, 9Walsh R.M. Ackroyd F.W. Shellito P.C. Endoscopic resection of large sessile colorectal polyps.Gastrointest Endosc. 1992; 38: 303-309Abstract Full Text PDF PubMed Scopus (191) Google Scholar, 10Iishi H. Tatsuta M. Iseki K. et al.Endoscopic piecemeal resection with submucosal saline injection of large sessile colorectal polyps.Gastrointest Endosc. 2000; 51: 697-700Abstract Full Text Full Text PDF PubMed Scopus (143) Google Scholar, 11Conio M. Repici A. Demarquay J.F. et al.EMR of large sessile colorectal polyps.Gastrointest Endosc. 2004; 60: 234-241Abstract Full Text Full Text PDF PubMed Scopus (187) Google Scholar, 12Regula J. Wronska E. Polkowski M. et al.Argon plasma coagulation after piecemeal polypectomy of sessile colorectal adenomas: long-term follow-up study.Endoscopy. 2003; 35: 212-218Crossref PubMed Scopus (127) Google Scholar, 13Higaki S. Hashimoto S. Harada K. et al.Long-term follow-up of large flat colorectal tumors resected endoscopically.Endoscopy. 2003; 35: 845-849Crossref PubMed Scopus (109) Google Scholar, 14Bories E. Pesenti C. Monges G. et al.Endoscopic mucosal resection for advanced sessile adenoma and early-stage colorectal carcinoma.Endoscopy. 2006; 38: 231-235Crossref PubMed Scopus (71) Google Scholar as well as better eradication with snaring techniques compared with forceps removal of small polyps,32Ellis K. Shiel M. Marquis S. et al.Efficacy of hot biopsy forceps, cold micro-snare and microsnare with cautery techniques in the removal of diminutive colonic polyps.Gastrointest Endosc. 1997; 45 (abstract): AB107Abstract Full Text PDF Scopus (47) Google Scholar support the suggestion that some of our technical approaches to polypectomy are more effective than others. A survey in 200433Singh N. Harrison M. Rex D.K. A survey of colonoscopic polypectomy practices among clinical gastroenterologists.Gastrointest Endosc. 2004; 99: 414-418Abstract Full Text Full Text PDF Scopus (142) Google Scholar confirmed that polypectomy technique among U.S. gastroenterologists is highly variable (Table 2).Table 2Techniques for Small (<1 cm in Size) Polyp Removal by U.S. Clinical GastroenterologistsaPercent of physicians stating that they use this method to remove polyps of the given size.Polyp sizeCold forcepsCold snaresHot forcepsHot snaresMixed methods1–3 mm50.3%aPercent of physicians stating that they use this method to remove polyps of the given size.4.8%33.3%4.8%5.9%4–6 mm18.5%14.8%21.2%31.2%14.4%7–9 mm2.1%5.8%4.2%79.9%7.8%Adapted from reference 22Fujishiro M. Yahagi N. Kakushima N. et al.Successful nonsurgical management of perforation complicating endoscopic submucosal dissection of gastrointestinal epithelial neoplasms.Endoscopy. 2006; 38: 1001-1006Crossref PubMed Scopus (157) Google Scholar.a Percent of physicians stating that they use this method to remove polyps of the given size. Open table in a new tab In addition to the probability that variable polypectomy technique affects the success of polyp eradication, variable polypectomy technique almost certainly also affects complication rates. The most serious complication of polypectomy is perforation, and most colonoscopy perforations are polypectomy-related.34Levin T.R. Zhao W. Conell C. et al.Complications of colonoscopy in an integrated health care delivery system.Ann Intern Med. 2006; 145: 880-886Crossref PubMed Scopus (429) Google Scholar The perforation rate of colonoscopy in the U.S. Medicare population has been estimated at 1 in 500 overall and 1 in 1000 in screening patients.35Gatto N.M. Frucht H. Sundararajan V. et al.Risk of perforation after colonoscopy and sigmoidoscopy: a population-based study.J Natl Cancer Inst. 2003; 95: 230-236Crossref PubMed Scopus (410) Google Scholar If indeed we are doing 14 million colonoscopies per year, this would correspond to up to 14,000 perforations and perhaps several hundred colonoscopic perforation-related deaths per year, mostly from polypectomy. There has been the repeated suggestion that essentially all polypectomy-related perforations are from electrocautery, and that electrocautery is not necessary to remove small polyps effectively.36Tappero G. Gaia E. De Giuli P. et al.Cold snare excision of small colorectal polyps.Gastrointest Endosc. 1992; 38: 310-313Abstract Full Text PDF PubMed Scopus (146) Google Scholar, 37Deenadayalu V.P. Rex D.K. Colon polyp retrieval after cold snaring.Gastrointest Endosc. 2005; 62: 253-256Abstract Full Text Full Text PDF PubMed Scopus (80) Google Scholar In the absence of definitive trials, polypectomy techniques for small polyps have been quite variable (Table 2), and we remain unable to state whether specific techniques are clearly superior with regard to the outcomes of polyp eradication and safety. Given that 80% of colorectal polyps are ≤5 mm in size and 90% are ≤9 mm in size and that most polypectomy complications result from small polyp removal34Levin T.R. Zhao W. Conell C. et al.Complications of colonoscopy in an integrated health care delivery system.Ann Intern Med. 2006; 145: 880-886Crossref PubMed Scopus (429) Google Scholar because small polyps are so numerous, the issue of how best to remove small polyps is not trivial.Considering the situation overall, including the large number of polypectomies being performed, the importance of polypectomy to cancer prevention, the large total number of complications, the evidence of variable technique, and the suggestions that technique affects outcome, polypectomy technique is deserving of more study to define what techniques constitute best practice. Furthermore, although diagnostic colonoscopy might be threatened with extinction,38Regueiro C.R. Will screening colonoscopy disappear and transform gastroenterology practice? threats to clinical practice and recommendations to reduce their impact: report of a consensus conference conducted by the AGA Institute Future Trends Committee.Gastroenterology. 2006; 131: 1287-1312Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar polypectomy is not; thus, any poor outcomes caused by polypectomy techniques that are less effective or riskier will persist as a public health issue.In all likelihood, endoscopists practice polypectomy as they were taught and probably see little rationale for changing and have little comfort with changing when there is so little hard evidence that mandates change. We have seen a few randomized controlled trials on polypectomy technique,15Brooker J.C. Saunders B.P. Shah S.G. et al.Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations.Gastrointest Endosc. 2002; 55: 371-375Abstract Full Text Full Text PDF PubMed Scopus (251) Google Scholar, 39Shioji K. Suzuki Y. Kobayashi M. et al.Prophylactic clip application does not decrease delayed bleeding after colonoscopic polypectomy.Gastrointest Endosc. 2003; 57: 691-694Abstract Full Text Full Text PDF PubMed Scopus (207) Google Scholar, 40Di Giorgio P. De Luca L. Calcagno G. et al.Detachable snare versus epinephrine injection in the prevention of postpolypectomy bleeding: a randomized and controlled study.Endoscopy. 2004; 36: 860-863Crossref PubMed Scopus (147) Google Scholar, 41Paspatis G.A. Paraskeva K. Theodoropoulou A. et al.A prospective, randomized comparison of adrenaline injection in combination with detachable snare versus adrenaline injection alone in the prevention of postpolypectomy bleeding in large colonic polyps.Am J Gastroenterol. 2006; 101: 2805-2809Crossref PubMed Scopus (80) Google Scholar, 42Iishi H. Tatsuta M. Narahara H. et al.Endoscopic resection of large pedunculated colorectal polyps using a detachable snare.Gastrointest Endosc. 1996; 44: 594-597Abstract Full Text Full Text PDF PubMed Scopus (129) Google Scholar, 43Hsieh Y.H. Lin H.J. Tseng G.Y. et al.Is submucosal epinephrine injection necessary before polypectomy? a prospective, comparative study.Hepatogastroenterology. 2001; 48: 1379-1382PubMed Google Scholar primarily from outside the United States, and they are usually focused on ancillary techniques to prevent bleeding (Table 3). One can readily generate a list of questions that have not been answered in either randomized controlled trials or by other convincing study designs (Table 4). The problem in studying these issues is the large longitudinal studies that would often be needed to provide answers. Industry is unlikely to sponsor studies beyond those related to new device development. Perhaps our professional societies or the National Institutes of Health would consider funding if they can be convinced that defining best polypectomy technique is an important public health issue.Table 3Topics in Polypectomy Technique Addressed in Randomized Controlled TrialsEffectiveReferenceProphylactic clipping to prevent bleedingNo39Shioji K. Suzuki Y. Kobayashi M. et al.Prophylactic clip application does not decrease delayed bleeding after colonoscopic polypectomy.Gastrointest Endosc. 2003; 57: 691-694Abstract Full Text Full Text PDF PubMed Scopus (207) Google ScholarDetachable snares to prevent bleedingYes40Di Giorgio P. De Luca L. Calcagno G. et al.Detachable snare versus epinephrine injection in the prevention of postpolypectomy bleeding: a randomized and controlled study.Endoscopy. 2004; 36: 860-863Crossref PubMed Scopus (147) Google Scholar, 41Paspatis G.A. Paraskeva K. Theodoropoulou A. et al.A prospective, randomized comparison of adrenaline injection in combination with detachable snare versus adrenaline injection alone in the prevention of postpolypectomy bleeding in large colonic polyps.Am J Gastroenterol. 2006; 101: 2805-2809Crossref PubMed Scopus (80) Google Scholar, 42Iishi H. Tatsuta M. Narahara H. et al.Endoscopic resection of large pedunculated colorectal polyps using a detachable snare.Gastrointest Endosc. 1996; 44: 594-597Abstract Full Text Full Text PDF PubMed Scopus (129) Google ScholarEpinephrine to prevent immediate bleedingYes40Di Giorgio P. De Luca L. Calcagno G. et al.Detachable snare versus epinephrine injection in the prevention of postpolypectomy bleeding: a randomized and controlled study.Endoscopy. 2004; 36: 860-863Crossref PubMed Scopus (147) Google Scholar, 41Paspatis G.A. Paraskeva K. Theodoropoulou A. et al.A prospective, randomized comparison of adrenaline injection in combination with detachable snare versus adrenaline injection alone in the prevention of postpolypectomy bleeding in large colonic polyps.Am J Gastroenterol. 2006; 101: 2805-2809Crossref PubMed Scopus (80) Google ScholarRoutine APC in reducing recurrence after piecemeal polypectomyYes15Brooker J.C. Saunders B.P. Shah S.G. et al.Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations.Gastrointest Endosc. 2002; 55: 371-375Abstract Full Text Full Text PDF PubMed Scopus (251) Google ScholarAPC, argon plasma coagulation. Open table in a new tab Table 4Questions About Colonoscopic Polypectomy not Addressed in Randomized Controlled Trials1Does submucosal injection prevent perforation?2Are cold snaring and hot snaring comparable for eradication of small polyps?3Does cold snaring produce fewer complications than hot forceps and hot snaring?4What size sessile polyps can be safely removed in one piece by snare polypectomy (after submucosal injection), and how is this affected by location in the colon?5What size pieces can be safely removed during piecemeal polypectomy by snare polypectomy, and how is that affected by location in the colon?6Does snare size or shape affect the efficiency or eradication success of small or large polyp removal?7How does current selection affect the complication rate or eradication success of polypectomy (eg, coagulation vs cutting vs blended)?8Can real-time histology (eg, narrow band imaging, confocal laser microscopy, autofluorescence) replace submission of small polyps for histologic assessment without alteration of outcomes?9Are the outcomes (eg, effective polyp eradication, loss of patients to follow-up before verification of eradication, complications, cost of initial therapy, total costs of therapy) different for piecemeal polypectomy compared with ESD?10What are the outcomes and cost-effectiveness of piecemeal polypectomy (or ESD) compared with laparoscopic colectomy for large sessile polyps, and how is this affected by polyp size and location in the colon? Open table in a new tab I congratulate our Japanese colleagues on their achievements in ESD and look forward to developments in ESD technique that will make it more practical. Until then, let us not take other aspects of polypectomy practice for granted. Polypectomy is a cornerstone of gastrointestinal practice. Variable technique might have important effects on very clinically relevant outcomes. We owe it to our patients to define those techniques with the best outcomes. In this issue, Fujishiro et al1Fujishiro M. et al.Outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms obtained in 200 consecutive cases.Clin Gastroenterol Hepatol. 2007; 5: 678-683Abstract Full Text Full Text PDF PubMed Scopus (309) Google Scholar report their experience with endoscopic submucosal dissection (ESD) of 200 large colorectal polyps. ESD was developed in Japan to improve the curative endoscopic resection of early gastric neoplasms, and ESD has recently been extended to the rectum and colon. The technical skills involved in ESD, which have been demonstrated on video at a number of North American meetings, are impressive and leave American endoscopists humbled and with a familiar sense of inferiority with respect to our Japanese colleagues. The technique starts with submucosal injection of a long-acting solution, followed by circumferential incision into the submucosa around the perimeter of the lesion, followed by submucosal dissection until the polyp is delivered, in one piece (en bloc resection) if possible. There were 12 perforations (6%) in the series, but only 1 required surgical resection. Patients were observed post-ESD in the hospital and discharged within 1 week. The recurrence rate at follow-up was only 1.8% and was 0% among the nearly 90% of patients with successful en bloc resection. There are excellent recent summaries of ESD technique2Kodashima S. Fujishiro M. Yahagi N. et al.Endoscopic submucosal dissection using flexknife.J Clin Gastroenterol. 2006; 40: 378-384Crossref PubMed Scopus (65) Google Scholar and commentaries on ESD3Das A. Endoscopic submucosal dissection: cure in one piece.Endoscopy. 2006; 38: 1044-1046Crossref PubMed Scopus (10) Google Scholar available. What is the rationale for ESD? First, the initial cure rate with ESD is much higher than that of traditional piecemeal polypectomy. Piecemeal technique has a failure rate at first follow-up that ranges from 14%–55%.4Binmoeller K.F. Bohnacker S. Seifert H. et al.Endoscopic snare excision of "giant" colorectal polyps.Gastrointest Endosc. 1996; 43: 183-188Abstract Full Text Full Text PDF PubMed Scopus (193) Google Scholar, 5Zlatanic J. Waye J.D. Kim P.S. et al.Large sessile colonic adenomas: use of argon plasma coagulator to supplement piecemeal snare polypectomy.Gastrointest Endosc. 1999; 49: 731-735Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 6Church J.M. Experience in the endoscopic management of large colonic polyps.ANZ J Surg. 2003; 73: 988-995Crossref PubMed Scopus (86) Google Scholar, 7Brooker J.C. Saunders B.P. Shah S.G. et al.Endoscopic resection of large sessile colonic polyps by specialist and non-specialist endoscopists.Br J Surg. 2002; 89: 1020-1024Crossref PubMed Scopus (72) Google Scholar, 8Doniec J.M. Lohnert M.S. Schniewind B. et al.Endoscopic removal of large colorectal polyps: prevention of unnecessary surgery?.Dis Colon Rectum. 2003; 46: 340-348Crossref PubMed Scopus (131) Google Scholar, 9Walsh R.M. Ackroyd F.W. Shellito P.C. Endoscopic resection of large sessile colorectal polyps.Gastrointest Endosc. 1992; 38: 303-309Abstract Full Text PDF PubMed Scopus (191) Google Scholar, 10Iishi H. Tatsuta M. Iseki K. et al.Endoscopic piecemeal resection with submucosal saline injection of large sessile colorectal polyps.Gastrointest Endosc. 2000; 51: 697-700Abstract Full Text Full Text PDF PubMed Scopus (143) Google Scholar, 11Conio M. Repici A. Demarquay J.F. et al.EMR of large sessile colorectal polyps.Gastrointest Endosc. 2004; 60: 234-241Abstract Full Text Full Text PDF PubMed Scopus (187) Google Scholar, 12Regula J. Wronska E. Polkowski M. et al.Argon plasma coagulation after piecemeal polypectomy of sessile colorectal adenomas: long-term follow-up study.Endoscopy. 2003; 35: 212-218Crossref PubMed Scopus (127) Google Scholar, 13Higaki S. Hashimoto S. Harada K. et al.Long-term follow-up of large flat colorectal tumors resected endoscopically.Endoscopy. 2003; 35: 845-849Crossref PubMed Scopus (109) Google Scholar, 14Bories E. Pesenti C. Monges G. et al.Endoscopic mucosal resection for advanced sessile adenoma and early-stage colorectal carcinoma.Endoscopy. 2006; 38: 231-235Crossref PubMed Scopus (71) Google Scholar These failures probably result from the inability to fully snare resect very flat portions that are present in many large sessile polyps, and survival of clusters of dysplastic cells in the flat portions and at the margin of the polyp and at the borders of resected pieces. Effective ablation of these flat areas and the polyp edges reduces the chance of residual polyp at first follow-up15Brooker J.C. Saunders B.P. Shah S.G. et al.Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations.Gastrointest Endosc. 2002; 55: 371-375Abstract Full Text Full Text PDF PubMed Scopus (251) Google Scholar but is still less effective than ESD. Second, ESD greatly improves the quality of the pathologic specimen, allowing greater assurance that the lateral and deep margins are free of neoplasia. Despite these advantages, ESD has limitations that will slow or prevent its spread to the United States in the near future (Table 1). First, in its current form it is not an efficient method of removing polyps. Although Fujishiro et al1Fujishiro M. et al.Outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms obtained in 200 consecutive cases.Clin Gastroenterol Hepatol. 2007; 5: 678-683Abstract Full Text Full Text PDF PubMed Scopus (309) Google Scholar did not describe times to complete ESD, resection times of 3–5 hours have been reported for performance of ESD in the stomach or colon.16Shimura T. Sasaki M. Kataoka H. et al.Advantages of endoscopic submucosal dissection over conventional endoscopic mucosal resection.J Gastroenterol Hepatol. 2006; (published online July 18:1-6.)Google Scholar, 17Fujishiro M. Yahagi N. Kakushima N. et al.Successful endoscopic en bloc resection of a large laterally spreading tumor in the rectosigmoid junction by endoscopic submucosal dissection.Gastrointest Endosc. 2006; 63: 178-183Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar Piecemeal polypectomy of large sessile polyps, which requires procedure times about 2-fold to 2.5-fold longer than colonoscopy with removal of small polyps,18Overhiser A. Rex D.K. Resources required for resection of large sessile colon polyps.Gastrointest Endosc. 2006; 63: AB202Abstract Full Text Full Text PDF Google Scholar is anecdotally considered to be too inefficient (and too dangerous) by many American endoscopists, and many endoscopically resectable polyps in the United States are being sent for surgical resection.19Onken J.E. Friedman J.Y. Subramanian S. et al.Treatment patterns and costs associated with sessile colorectal polyps.Am J Gastroenterol. 2002; 97: 2896-2901Crossref PubMed Scopus (40) Google Scholar From a practice perspective, spending multiple hours on endoscopic resection of a polyp is unlikely to be accepted on any significant scale in the United States without substantial adjustment in reimbursement. If ESD becomes efficient, training American endoscopists in ESD (or a subset of endoscopists at referral centers) will be an obstacle if it remains as technically demanding as it is currently. Other obstacles to ESD in the United States are the high perforation rates of ESD and teaching American endoscopists to recognize small perforations and close them with clips.20Heldwein W. Dollhopf M. Rosch T. et al.The Munich Polypectomy Study (MUPS): prospective analysis of complications and risk factors in 4000 colonic snare polypectomies.Endoscopy. 2005; 37: 1116-1122Crossref PubMed Scopus (288) Google Scholar, 21Taku K. Sano Y. Fu K.I. et al.Iatrogenic perforation at therapeutic colonoscopy: should the endoscopist attempt closure using endoclips or transfer immediately to surgery?.Endoscopy. 2006; 38: 428Crossref PubMed Scopus (38) Google Scholar, 22Fujishiro M. Yahagi N. Kakushima N. et al.Successful nonsurgical management of perforation complicating endoscopic submucosal dissection of gastrointestinal epithelial neoplasms.Endoscopy. 2006; 38: 1001-1006Crossref PubMed Scopus (157) Google Scholar Fear of perforation might be greater in the United States because the medicolegal environment is different (worse) than in Japan, and because even complex polypectomy in the United States is typically an outpatient procedure. ESD is a powerful concept, however, and development of easy-to-use, safe, and efficient systems to perform ESD should be a priority for endoscope and accessory manufacturers and endoscopic investigators. When ESD technique is more fully developed, it would help to conduct randomized comparisons of ESD with piecemeal polypectomy, particularly if ESD remains so time-consuming, focused on whether the long-term outcomes and costs of ESD and piecemeal polypectomy are substantially different. If we accept the suggestion that ESD is not ready for prime time in the United States, where does that leave colonoscopic polypectomy practice in our country? Should we be satisfied with our current polypectomy practices? Is this an important topic that deserves increased attention, study, and resources? How much do polypectomy techniques vary between endoscopists, and do different techniques result in substantially different outcomes? Our main technical goals in colonoscopic polypectomy are effective eradication of polyps, minimal complications, and efficiency in completion of polypectomy and retrieval of specimens. In the United States, it has been estimated that more than 14 million colonoscopies per year are performed,23Seeff L.C. Richards T.B. Shapiro J.A. et al.How many endoscopies are performed for colorectal cancer screening? results from CDC's survey of endoscopic capacity.Gastroenterology. 2004; 127: 1670-1677Abstract Full Text Full Text PDF PubMed Scopus (365) Google Scholar of which a substantial fraction (for careful colonoscopists more than half)24Barclay R. Vicari J.J. Johanson J.F. et al.Effect of a pre-specified minimum colonoscopic withdrawal time on adenoma detection rates during screening colonoscopy.Gastrointest Endosc. 2006; 63: AB83Google Scholar include 1 or more polypectomies. Polypectomy is the means of preventing colorectal cancer during colonoscopy25Winawer S.J. Zauber A.G. Ho M.N. et al.Prevention of colorectal cancer by colonoscopic polypectomy: the National Polyp Study Workgroup.N Engl J Med. 1993; 329: 1977-1981Crossref PubMed Scopus (3862) Google Scholar, 26Citarda F. Tomaselli G. Capocaccia R. et al.Efficacy in standard clinical practice of colonoscopic polypectomy in reducing colorectal cancer incidence.Gut. 2001; 48: 812-815Crossref PubMed Scopus (611) Google Scholar and is the most important therapeutic procedure in gastrointestinal medicine. The National Polyp Study estimated that polypectomy prevented 76%–90% of incident colorectal cancers,25Winawer S.J. Zauber A.G. Ho M.N. et al.Prevention of colorectal cancer by colonoscopic polypectomy: the National Polyp Study Workgroup.N Engl J Med. 1993; 329: 1977-1981Crossref PubMed Scopus (3862) Google Scholar suggesting that our current polypectomy techniques are quite effective. On the other hand, U.S. dietary intervention27Schatzkin A. Lanza E. Corle D. et al.Lack of effect of a low-fat, high-fiber diet on the recurrence of colorectal adenomas: Polyp Prevention Trial Study Group.N Engl J Med. 2000; 342: 1149-1155Crossref PubMed Scopus (827) Google Scholar, 28Alberts D.S. Martinez M.E. Roe D.J. et al.Lack of effect of a high-fiber cereal supplement on the recurrence of colorectal adenomas: Phoenix Colon Cancer Prevention Physicians' Network.N Engl J Med. 2000; 342: 1156-1162Crossref PubMed Scopus (725) Google Scholar and chemoprevention29Robertson D.J. Greenberg E.R. Beach M. et al.Colorectal cancer in patients under close colonoscopic surveillance.Gastroenterology. 2005; 129: 34-41Abstract Full Text Full Text PDF PubMed Scopus (388) Google Scholar studies showed a much lower preventive effect against colorectal cancer by colonoscopy and polypectomy. Two studies have suggested that more than 25% of cancers that develop after colonoscopy might result from ineffective polypectomy.30Pabby A. Schoen R.E. Weissfeld J.L. et al.Analysis of colorectal cancer occurrence during surveillance colonoscopy in the dietary Polyp Prevention Trial.Gastrointest Endosc. 2005; 61: 385-391Abstract Full Text Full Text PDF PubMed Scopus (312) Google Scholar, 31Farrar W.D. Sawhney M.S. Nelson D.B. et al.Colorectal cancers found after a complete colonoscopy.Clin Gastroenterol Hepatol. 2006; 4: 1259-1264Abstract Full Text Full Text PDF PubMed Scopus (260) Google Scholar This and the widely variable success rates of eradication of large sessile polyps with piecemeal technique,4Binmoeller K.F. Bohnacker S. Seifert H. et al.Endoscopic snare excision of "giant" colorectal polyps.Gastrointest Endosc. 1996; 43: 183-188Abstract Full Text Full Text PDF PubMed Scopus (193) Google Scholar, 5Zlatanic J. Waye J.D. 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Endoscopic resection of large sessile colorectal polyps.Gastrointest Endosc. 1992; 38: 303-309Abstract Full Text PDF PubMed Scopus (191) Google Scholar, 10Iishi H. Tatsuta M. Iseki K. et al.Endoscopic piecemeal resection with submucosal saline injection of large sessile colorectal polyps.Gastrointest Endosc. 2000; 51: 697-700Abstract Full Text Full Text PDF PubMed Scopus (143) Google Scholar, 11Conio M. Repici A. Demarquay J.F. et al.EMR of large sessile colorectal polyps.Gastrointest Endosc. 2004; 60: 234-241Abstract Full Text Full Text PDF PubMed Scopus (187) Google Scholar, 12Regula J. Wronska E. Polkowski M. et al.Argon plasma coagulation after piecemeal polypectomy of sessile colorectal adenomas: long-term follow-up study.Endoscopy. 2003; 35: 212-218Crossref PubMed Scopus (127) Google Scholar, 13Higaki S. Hashimoto S. Harada K. et al.Long-term follow-up of large flat colorectal tumors resected endoscopically.Endoscopy. 2003; 35: 845-849Crossref PubMed Scopus (109) Google Scholar, 14Bories E. Pesenti C. Monges G. et al.Endoscopic mucosal resection for advanced sessile adenoma and early-stage colorectal carcinoma.Endoscopy. 2006; 38: 231-235Crossref PubMed Scopus (71) Google Scholar as well as better eradication with snaring techniques compared with forceps removal of small polyps,32Ellis K. Shiel M. Marquis S. et al.Efficacy of hot biopsy forceps, cold micro-snare and microsnare with cautery techniques in the removal of diminutive colonic polyps.Gastrointest Endosc. 1997; 45 (abstract): AB107Abstract Full Text PDF Scopus (47) Google Scholar support the suggestion that some of our technical approaches to polypectomy are more effective than others. A survey in 200433Singh N. Harrison M. Rex D.K. A survey of colonoscopic polypectomy practices among clinical gastroenterologists.Gastrointest Endosc. 2004; 99: 414-418Abstract Full Text Full Text PDF Scopus (142) Google Scholar confirmed that polypectomy technique among U.S. gastroenterologists is highly variable (Table 2). Adapted from reference 22Fujishiro M. Yahagi N. Kakushima N. et al.Successful nonsurgical management of perforation complicating endoscopic submucosal dissection of gastrointestinal epithelial neoplasms.Endoscopy. 2006; 38: 1001-1006Crossref PubMed Scopus (157) Google Scholar. In addition to the probability that variable polypectomy technique affects the success of polyp eradication, variable polypectomy technique almost certainly also affects complication rates. The most serious complication of polypectomy is perforation, and most colonoscopy perforations are polypectomy-related.34Levin T.R. Zhao W. Conell C. et al.Complications of colonoscopy in an integrated health care delivery system.Ann Intern Med. 2006; 145: 880-886Crossref PubMed Scopus (429) Google Scholar The perforation rate of colonoscopy in the U.S. Medicare population has been estimated at 1 in 500 overall and 1 in 1000 in screening patients.35Gatto N.M. Frucht H. Sundararajan V. et al.Risk of perforation after colonoscopy and sigmoidoscopy: a population-based study.J Natl Cancer Inst. 2003; 95: 230-236Crossref PubMed Scopus (410) Google Scholar If indeed we are doing 14 million colonoscopies per year, this would correspond to up to 14,000 perforations and perhaps several hundred colonoscopic perforation-related deaths per year, mostly from polypectomy. There has been the repeated suggestion that essentially all polypectomy-related perforations are from electrocautery, and that electrocautery is not necessary to remove small polyps effectively.36Tappero G. Gaia E. De Giuli P. et al.Cold snare excision of small colorectal polyps.Gastrointest Endosc. 1992; 38: 310-313Abstract Full Text PDF PubMed Scopus (146) Google Scholar, 37Deenadayalu V.P. Rex D.K. Colon polyp retrieval after cold snaring.Gastrointest Endosc. 2005; 62: 253-256Abstract Full Text Full Text PDF PubMed Scopus (80) Google Scholar In the absence of definitive trials, polypectomy techniques for small polyps have been quite variable (Table 2), and we remain unable to state whether specific techniques are clearly superior with regard to the outcomes of polyp eradication and safety. Given that 80% of colorectal polyps are ≤5 mm in size and 90% are ≤9 mm in size and that most polypectomy complications result from small polyp removal34Levin T.R. Zhao W. Conell C. et al.Complications of colonoscopy in an integrated health care delivery system.Ann Intern Med. 2006; 145: 880-886Crossref PubMed Scopus (429) Google Scholar because small polyps are so numerous, the issue of how best to remove small polyps is not trivial. Considering the situation overall, including the large number of polypectomies being performed, the importance of polypectomy to cancer prevention, the large total number of complications, the evidence of variable technique, and the suggestions that technique affects outcome, polypectomy technique is deserving of more study to define what techniques constitute best practice. Furthermore, although diagnostic colonoscopy might be threatened with extinction,38Regueiro C.R. Will screening colonoscopy disappear and transform gastroenterology practice? threats to clinical practice and recommendations to reduce their impact: report of a consensus conference conducted by the AGA Institute Future Trends Committee.Gastroenterology. 2006; 131: 1287-1312Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar polypectomy is not; thus, any poor outcomes caused by polypectomy techniques that are less effective or riskier will persist as a public health issue. In all likelihood, endoscopists practice polypectomy as they were taught and probably see little rationale for changing and have little comfort with changing when there is so little hard evidence that mandates change. We have seen a few randomized controlled trials on polypectomy technique,15Brooker J.C. Saunders B.P. Shah S.G. et al.Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations.Gastrointest Endosc. 2002; 55: 371-375Abstract Full Text Full Text PDF PubMed Scopus (251) Google Scholar, 39Shioji K. Suzuki Y. Kobayashi M. et al.Prophylactic clip application does not decrease delayed bleeding after colonoscopic polypectomy.Gastrointest Endosc. 2003; 57: 691-694Abstract Full Text Full Text PDF PubMed Scopus (207) Google Scholar, 40Di Giorgio P. De Luca L. Calcagno G. et al.Detachable snare versus epinephrine injection in the prevention of postpolypectomy bleeding: a randomized and controlled study.Endoscopy. 2004; 36: 860-863Crossref PubMed Scopus (147) Google Scholar, 41Paspatis G.A. Paraskeva K. Theodoropoulou A. et al.A prospective, randomized comparison of adrenaline injection in combination with detachable snare versus adrenaline injection alone in the prevention of postpolypectomy bleeding in large colonic polyps.Am J Gastroenterol. 2006; 101: 2805-2809Crossref PubMed Scopus (80) Google Scholar, 42Iishi H. Tatsuta M. Narahara H. et al.Endoscopic resection of large pedunculated colorectal polyps using a detachable snare.Gastrointest Endosc. 1996; 44: 594-597Abstract Full Text Full Text PDF PubMed Scopus (129) Google Scholar, 43Hsieh Y.H. Lin H.J. Tseng G.Y. et al.Is submucosal epinephrine injection necessary before polypectomy? a prospective, comparative study.Hepatogastroenterology. 2001; 48: 1379-1382PubMed Google Scholar primarily from outside the United States, and they are usually focused on ancillary techniques to prevent bleeding (Table 3). One can readily generate a list of questions that have not been answered in either randomized controlled trials or by other convincing study designs (Table 4). The problem in studying these issues is the large longitudinal studies that would often be needed to provide answers. Industry is unlikely to sponsor studies beyond those related to new device development. Perhaps our professional societies or the National Institutes of Health would consider funding if they can be convinced that defining best polypectomy technique is an important public health issue. APC, argon plasma coagulation. I congratulate our Japanese colleagues on their achievements in ESD and look forward to developments in ESD technique that will make it more practical. Until then, let us not take other aspects of polypectomy practice for granted. Polypectomy is a cornerstone of gastrointestinal practice. Variable technique might have important effects on very clinically relevant outcomes. We owe it to our patients to define those techniques with the best outcomes.