Index colonoscopy-related risk factors for postcolonoscopy colorectal cancers

• Published in: Gastrointestinal endoscopy 2019-01, Vol.89 (1), p.168-176.e3
• Main Authors: Tollivoro, Theodore A., Jensen, Christopher D., Marks, Amy R., Zhao, Wei K., Schottinger, Joanne E., Quinn, Virginia P., Ghai, Nirupa R., Zauber, Ann G., Doubeni, Chyke A., Levin, Theodore R., Fireman, Bruce, Quesenberry, Charles P., Corley, Douglas A.
• Format: Article
• Language: English
• Subjects: Adenocarcinoma - epidemiology; Adenoma - epidemiology; Adenoma - pathology; Adenoma - surgery; Aged; Aged, 80 and over; Case-Control Studies; Colonic Polyps - epidemiology; Colonic Polyps - pathology; Colonic Polyps - surgery; Colonoscopy; Colorectal Neoplasms - epidemiology; Colorectal Neoplasms - pathology; Colorectal Neoplasms - surgery; Early Detection of Cancer; Female; Humans; Logistic Models; Male; Middle Aged; Multivariate Analysis; Odds Ratio; Risk Factors; Tumor Burden
• ISSN: 0016-5107; 1097-6779
• DOI: 10.1016/j.gie.2018.08.023

Postcolonoscopy colorectal cancers (PCCRCs) are defined as those detected ≤10 years after an index colonoscopy negative for cancer, but modifiable risk factors are not well established in large, community-based populations. We evaluated risk factors from the index colonoscopy for PCCRCs diagnosed 1 to 10 years after an index colonoscopy using a case-control design. Odds ratios (OR) and 95% confidence intervals (CI) were adjusted for potential confounders. A proximal polyp ≥10 mm (OR, 8.18; 95% CI, 4.59-14.60), distal polyp ≥10 mm (OR, 3.30; 95% CI, 1.65-6.58), adenoma with (OR, 3.23; 95% CI, 1.83-5.68) and without advanced histology (OR, 1.87; 95% CI, 1.37-2.55), and an incomplete colonoscopy (OR, 5.52; 95% CI, 2.98-10.21) were associated with PCCRC. Risk factors for early versus late cancers (12-36 months vs >36 months to 10 years after examination) included incomplete polyp excision in the colonic segment of the subsequent cancer (OR, 4.76; 95% CI, 2.35-9.65); failure to examine the segment (OR, 2.42; 95% CI, 1.27-4.60); and a polyp ≥10 mm in the segment (OR, 2.38; 95% CI, 1.53-3.70). A total of 559 of 1206 patients with PCCRC (46.4%) had 1 or more risk factors that were significant for PCCRC (incomplete examination, large polyp, or any adenoma). In a large community-based study with comprehensive capture of PCCRCs, almost half of PCCRCs had potentially modifiable factors related to polyp surveillance or removal and examination completeness. These represent potential high-yield targets to further increase the effectiveness of colorectal cancer screening.