Adenoma and polyp detection rates during insertion versus withdrawal phase of colonoscopy: a systematic review and meta-analysis of randomized controlled trials

      Background and Aims

      Colonoscopy is the preferred modality for colorectal cancer screening because it has both diagnostic and therapeutic capabilities. Current consensus states that colonoscopy should be performed with initial rapid passage of the instrument to the cecum, followed by thorough evaluation for and removal of all polyps during a deliberate slow withdrawal. Reports have suggested that polyps that are seen but not removed during insertion are sometimes quite difficult to find during withdrawal.


      We performed a comprehensive literature search of several major databases (from inception to March 2020) to identify randomized controlled trials comparing inspection and polypectomy during the insertion phase as opposed to the traditional practice of inspection and polypectomy performed entirely during the withdrawal phase. We examined differences in terms of adenoma detection rate (ADR), polyps detected per patient (PDPP), cecal intubation time (CIT), withdrawal time, and total procedure time.


      Seven randomized controlled trials, including 3834 patients, were included in our final analysis. The insertion/withdrawal cohort had 1951 patients and the withdrawal-only cohort 1883 patients. Pooled odds of adenoma detection in the insertion/withdrawal cohort was .99 (P = .8). ADR was 47.2% in the insertion/withdrawal cohort and 48.6% in the withdrawal-only cohort. Although total procedure and withdrawal times were shorter in the insertion/withdrawal cohort, PDPP in both cohorts were not statistically significant (1.4 vs 1.5, P = .7).


      Additional inspection and polypectomy during the insertion and withdrawal phases of colonoscopy offer no additional benefit in terms of ADR or PDPP.


      ADR (adenoma detection rate), CI (confidence interval), CIT (cecal intubation time), PDPP (polyps detected per patient), TPT (total procedure time), WT (withdrawal time)
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        • Siegel R.L.
        • Miller K.D.
        • Jemal A.
        Cancer statistics, 2020.
        CA Cancer J Clin. 2020; 70: 7-30
        • Ward E.M.
        • Sherman R.L.
        • Henley S.J.
        • et al.
        Annual report to the nation on the status of cancer, featuring cancer in men and women age 20-49 years.
        J Natl Cancer Inst. 2019; 111: 1279-1297
        • Doubeni C.A.
        • Corley D.A.
        • Quinn V.P.
        • et al.
        Effectiveness of screening colonoscopy in reducing the risk of death from right and left colon cancer: a large community-based study.
        Gut. 2018; 67: 291-298
        • van Rijn J.C.
        • Reitsma J.B.
        • Stoker J.
        • et al.
        Polyp miss rate determined by tandem colonoscopy: a systematic review.
        Am J Gastroenterol. 2006; 101: 343-350
        • Teramoto A.
        • Iwatate M.
        • Hirata D.
        • et al.
        Clinical importance of cold polypectomy during insertion phase in left side colon and rectum: a pilot study.
        J Gastroenterol Hepatol. 2018; 33: 132
        • Teramoto A.
        • Aoyama N.
        • Ebisutani C.
        • et al.
        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).
        Gastrointest Endosc. 2020; 91: 917-924
        • Jadad A.R.
        • Moore R.A.
        • Carroll D.
        • et al.
        Assessing the quality of reports of randomized clinical trials: Is blinding necessary?.
        Control Clin Trials. 1996; 17: 1-12
        • DerSimonian R.
        • Laird N.
        Meta-analysis in clinical trials.
        Control Clin Trials. 1986; 7: 177-188
        • Sutton A.J.
        • Abrams K.R.
        • Jones D.R.
        • et al.
        Methods for meta-analysis in medical research.
        J. Wiley, New York, NY2000
        • Higgins J.P.
        • Thompson S.G.
        • Spiegelhalter D.J.
        A re-evaluation of random-effects meta-analysis.
        J R Stat Soc Ser A Stat Soc. 2009; 172: 137-159
        • Riley R.D.
        • Higgins J.P.T.
        • Deeks J.J.
        Interpretation of random effects meta-analyses.
        BMJ. 2011; 342: d549
        • Mohan B.P.
        • Adler D.G.
        Heterogeneity in systematic review and meta-analysis: how to read between the numbers.
        Gastrointest Endosc. 2019; 89: 902-903
        • Higgins J.P.
        • Thompson S.G.
        • Deeks J.J.
        • et al.
        Measuring inconsistency in meta-analyses.
        BMJ. 2003; 327: 557-560
        • Kanwal F.
        • White D.
        Systematic reviews and meta-analyses in clinical gastroenterology and hepatology.
        Clin Gastroenterol Hepatol. 2012; 10: 1184-1186
        • Guyatt G.H.
        • Oxman A.D.
        • Kunz R.
        • et al.
        GRADE guidelines: 7. Rating the quality of evidence—inconsistency.
        J Clin Epidemiol. 2011; 64: 1294-1302
        • Easterbrook P.J.
        • Berlin J.A.
        • Gopalan R.
        • et al.
        Publication bias in clinical research.
        Lancet. 1991; 337: 867-872
        • Duval S.
        • Tweedie R.
        Trim and fill: a simple funnel-plot–based method of testing and adjusting for publication bias in meta-analysis.
        Biometrics. 2000; 56: 455-463
        • Rothstein H.R.
        • Sutton A.J.
        • Borenstein M.
        Publication bias in meta-analysis: prevention, assessment and adjustments.
        John Wiley & Sons, Hoboken, NJ2005: 1-7
        • Gweon T.G.
        • Lee S.W.
        • Ji J.S.
        • et al.
        Comparison of adenoma detection by colonoscopy between polypectomy performed during both insertion and withdrawal versus during withdrawal only: a multicenter, randomized, controlled trial.
        Surg Endosc. 2020; 2020: 1-8
        • Cheng C.L.
        • Kuo Y.L.
        • Liu N.J.
        • et al.
        Comparison of polyp detection during both insertion and withdrawal versus only withdrawal of colonoscopy: a prospective randomized trial.
        J Gastroenterol Hepatol. 2019; 34: 1377-1383
        • Ji J.-S.
        • Lee S.-W.
        • Lee J.
        Comparison of adenoma detection by polypectomy during both insertion and withdrawal versus only withdrawal of colonoscopy: a randomized, controlled multicenter trial.
        Ann Oncol. 2016; 27: 69
        • Sanaka M.R.
        • Parsi M.A.
        • Burke C.A.
        • et al.
        Adenoma detection at colonoscopy by polypectomy in withdrawal only versus both insertion and withdrawal: a randomized controlled trial.
        Surg Endosc. 2015; 29: 692-699
        • Hewett D.G.
        • Rex D.K.
        Inspection on instrument insertion during colonoscopy: a randomized controlled trial.
        Gastrointest Endosc. 2012; 76: 381-387
        • Wildi S.
        • Schoepfer A.
        • Vavricka S.
        • et al.
        Colorectal polypectomy during insertion and withdrawal or only during withdrawal? A randomized controlled trial.
        Endoscopy. 2012; 44: 1019-1023
        • Sakamoto T.
        • Ramaraj R.
        • Tomizawa Y.
        • et al.
        Clinical significance of colorectal polyp detection on colonoscopy insertion.
        United Eur Gastroenterol J. 2019; 7: 125-129
        • Morini S.
        • Hassan C.
        • Zullo A.
        • et al.
        Detection of colonic polyps according to insertion/withdrawal phases of colonoscopy.
        Int J Colorectal Dis. 2009; 24: 527-530
        • Yang M.H.
        • Cho J.
        • Rampal S.
        • et al.
        The association between cecal insertion time and colorectal neoplasm detection.
        BMC Gastroenterol. 2013; 13: 124
        • von Renteln D.
        • Robertson D.J.
        • Bensen S.
        • et al.
        Prolonged cecal insertion time is associated with decreased adenoma detection.
        Gastrointest Endosc. 2017; 85: 574-580
        • Kim J.H.
        • Kim Y.-S.
        • Cheon J.H.
        • et al.
        Influence of the insertion time and number of polyps on miss rate in colonoscopy.
        Scand J Gastroenterol. 2011; 46: 634-639
        • Higuchi T.
        • Sugihara K.
        • Jass J.R.
        Demographic and pathological characteristics of serrated polyps of colorectum.
        Histopathology. 2005; 47: 32-40

      Linked Article

      • Inspection and polypectomy during insertion of colonoscopy: Is this the better way to go?
        Gastrointestinal EndoscopyVol. 93Issue 1
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          We read with interest the meta-analysis by Chandan et al1 investigating whether additional inspection and polypectomy during insertion of colonoscopy offer additional benefit. Debate about the colonoscopy examination strategies has become extremely active during recent years, and we also have a registered meta-analysis (PROSPERO: CRD42020172424) on this topic currently under review. We have some questions and comments regarding the review by Chandan et al.1
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