Improved detection of right colon adenomas with additional retroflexion following two forward-view examinations: a prospective study

Abstract

Background and study aims Colonoscopy in the right colon is less effective than in the left colon in screening for colorectal cancer. The aim of this study was to prospectively evaluate the diagnostic value of retroflexion in the right colon.

Patients and methods A total of 1020 patients undergoing screening or surveillance colonoscopy were enrolled. After the first cecal intubation, the scope was withdrawn from the cecum to the hepatic flexure in the standard forward view and all identified polyps were resected. A second examination from the cecum to the hepatic flexure was then performed in standard forward view, and finally a third examination of that same segment was conducted in retroflexion. Additionally detected polyps at each examination were removed. The main outcome measures included the proportion of procedures with successful retroflexion, the additional yield for adenoma detection, and the adenoma miss rate.

Results Retroflexion was successful in 840 patients (82.4 %). Retroflexion detected a significantly greater proportion of patients with adenomas in the proximal segment than the two standard examinations combined (forward view 25.5 % vs. total examination 27.5 %; P < 0.001). The per-adenoma miss rate of the two standard examinations in the right colon was 10.4 % (52/502), and the per-patient adenoma miss rate was 4.9 % (50/1020). The detection of additional adenomas using retroflexion was associated with age ≥ 55 years, gastroenterologist experience, and the presence of polyps on forward-view examination.

Conclusions Colonoscopic retroflexion in the proximal colon resulted in an increased detection of adenomas, even after two consecutive forward-view examinations.

Trial registered at Clinical Research Information Service (CRIS): KCT0000725.

• References

• 1 Lin OS, Kozarek RA, Cha JM. Impact of sigmoidoscopy and colonoscopy on colorectal cancer incidence and mortality: an evidence-based review of published prospective and retrospective studies. Intest Res 2014; 12: 268-274
• 2 Manser CN, Bachmann LM, Brunner J. et al. Colonoscopy screening markedly reduces the occurrence of colon carcinomas and carcinoma-related death: a closed cohort study. Gastrointest Endosc 2012; 76: 110-117
• 3 Van Rijn JC, Reitsma JB, Stoker J. et al. Polyp miss rate determined by tandem colonoscopy: a systematic review. Am J Gastroenterol 2006; 101: 343-350
• 4 Rex DK, Cutler CS, Lemmel GT. et al. Colonoscopic miss rates of adenomas determined by back-to-back colonoscopies. Gastroenterology 1997; 112: 24-28
• 5 Triantafyllou K, Tziatzios G, Sioulas AD. et al. Diagnostic yield of scope retroflexion in the right colon: a prospective cohort study. Dig Liver Dis 2016; 48: 176-181
• 6 Benson ME, Reichelderfer M, Said A. et al. Variation in colonoscopic technique and adenoma detection rates at an academic gastroenterology unit. Dig Dis Sci 2010; 55: 166-171
• 7 Brenner H, Hoffmeister M, Arndt V. et al. Protection from right- and left-sided colorectal neoplasms after colonoscopy: population-based study. J Natl Cancer Inst 2010; 102: 89-95
• 8 Rex DK. How I approach retroflexion and prevention of right-sided colon cancer following colonoscopy. Am J Gastroenterol 2016; 111: 9-11
• 9 Kushnir VM, Oh YS, Hollander T. et al. Impact of retroflexion vs. second forward view examination of the right colon on adenoma detection: a comparison study. Am J Gastroenterol 2015; 110: 415-422
• 10 Hanson JM, Atkin WS, Cunliffe WJ. et al. Rectal retroflexion: an essential part of lower gastrointestinal endoscopic examination. Dis Colon Rectum 2001; 44: 1706-1708
• 11 Harrison M, Singh N, Rex DK. Impact of proximal colon retroflexion on adenoma miss rates. Am J Gastroenterol 2004; 99: 519-522
• 12 Hewett DG, Rex DK. Miss rate of right-sided colon examination during colonoscopy defined by retroflexion: an observational study. Gastrointest Endosc 2011; 74: 246-252
• 13 Rex DK, Petrini JL, Baron TH. et al. Quality indicators for colonoscopy. Am J Gastroenterol 2006; 101: 873-885
• 14 Lee HS, Jeon SW. Is retroflexion helpful in detecting adenomas in the right colon? a single center interim analysis. Intest Res 2015; 13: 326-331
• 15 Winawer SJ, Zauber AG, Ho MN. et al. Prevention of colorectal cancer by colonoscopic polypectomy. The National Polyp Study Workgroup. N Engl J Med 1993; 329: 1977-1981
• 16 Singh H, Nugent Z, Demers AA. et al. The reduction in colorectal cancer mortality after colonoscopy varies by site of the cancer. Gastroenterology 2010; 139: 1128-1137
• 17 Lakoff J, Paszat LF, Saskin R. et al. Risk of developing proximal versus distal colorectal cancer after a negative colonoscopy: a population-based study. Clin Gastroenterol Hepatol 2008; 6: 1117-1121
• 18 Singh H, Nugent Z, Mahmud SM. et al. Predictors of colorectal cancer after negative colonoscopy: a population-based study. Am J Gastroenterol 2010; 105: 663-673
• 19 Soetikno RM, Kaltenbach T, Rouse RV. et al. Prevalence of nonpolypoid (flat and depressed) colorectal neoplasms in asymptomatic and symptomatic adults. JAMA 2008; 299: 1027-1035
• 20 Hetzel JT, Huang CS, Coukos JA. et al. Variation in the detection of serrated polyps in an average risk colorectal cancer screening cohort. Am J Gastroenterol 2010; 105: 2656-2664
• 21 Ng SC, Tsoi KK, Hirai HW. et al. The efficacy of cap-assisted colonoscopy in polyp detection and cecal intubation: a meta-analysis of randomized controlled trials. Am J Gastroenterol 2012; 107: 1165-1173
• 22 Westwood DA, Alexakis N, Connor SJ. Transparent cap-assisted colonoscopy versus standard adult colonoscopy: a systematic review and meta-analysis. Dis Colon Rectum 2012; 55: 218-225
• 23 Chandran S, Parker F, Vaughan R. et al. Right-sided adenoma detection with retroflexion versus forward-view colonoscopy. Gastrointest Endosc 2015; 81: 608-613