Likelihood of missed and recurrent adenomas in the proximal versus the distal colon
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Publisher version
UMass Chan Affiliations
Meyers Primary Care InstituteDepartment of Family Medicine and Community Health
Document Type
Journal ArticlePublication Date
2011-08-01Keywords
AdenomaAged
Colon, Ascending
Colon, Descending
Colon, Sigmoid
Colon, Transverse
Colonic Neoplasms
Colonoscopy
False Negative Reactions
FemaleHumansMaleMiddle AgedNeoplasm Recurrence, LocalProspective StudiesRegression AnalysisRisk FactorsCommunity Health and Preventive MedicinePreventive MedicinePrimary Care
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BACKGROUND: Colonoscopy may be less efficacious in reducing colorectal cancer mortality in the proximal compared with the distal colon. A greater likelihood for missed and recurrent adenomas in the proximal colon may contribute to this phenomenon. OBJECTIVE: To examine whether a proximal adenoma is associated with the risk and location of missed and recurrent adenomas. DESIGN: Prospective. SETTING: Polyp Prevention Trial. PARTICIPANTS: A total of 1864 patients with an adenoma at baseline underwent a follow-up colonoscopy 4 years later (adenoma recurrence). Of these, 1731 underwent a clearing colonoscopy 1 year after the baseline examination (missed adenoma). MAIN OUTCOME MEASUREMENTS: Association of baseline adenoma location with the risk and location of adenomas found at colonoscopy performed 1 year and 4 years later. RESULTS: At the year 1 colonoscopy, 598 patients (34.6%) had an adenoma (missed adenoma). Compared with those with a distal-only adenoma at baseline, patients with a proximal-only adenoma at baseline were more likely to have any missed adenomas (relative risk [RR] 1.28; 95% CI, 1.09-1.49) and a proximal-only missed adenoma (RR 2.05; 95% CI, 1.49-2.80). At the year 4 colonoscopy, 733 patients (39.3%) had adenoma recurrence. Patients with a baseline proximal-only adenoma were more likely to have any adenoma recurrence (RR 1.14; 95% CI, 1.00-1.31) and a proximal-only adenoma recurrence (RR 1.52; 95% CI, 1.15-2.02). Sensitivity analyses involving missed adenomas did not materially affect the risk or location of recurrent adenomas at year 4 colonoscopy. LIMITATION: Lesions may still be missed on repeated colonoscopies. CONCLUSIONS: Missed and recurrent adenomas are more likely to be in the proximal colon. Published by Mosby, Inc. All rights reserved.Source
Gastrointest Endosc. 2011 Aug;74(2):253-61. Epub 2011 May 6. Link to article on publisher's siteDOI
10.1016/j.gie.2011.02.023Permanent Link to this Item
http://hdl.handle.net/20.500.14038/30842PubMed ID
21549375Related Resources
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