Colonoscopy Is Associated With a Reduced Risk for Colon Cancer and Mortality in Patients With Inflammatory Bowel Diseases

Abstract

Background & Aims Crohn’s disease and ulcerative colitis are associated with increased risk of colorectal cancer (CRC). Surveillance colonoscopy is recommended at 2−3 year intervals beginning 8 years after diagnosis of inflammatory bowel disease (IBD). However, there have been no reports of whether colonoscopy examination reduces the risk for CRC in patients with IBD. Methods In a retrospective study, we analyzed data from 6823 patients with IBD (2764 with a recent colonoscopy, 4059 without a recent colonoscopy) seen and followed for at least 3 years at 2 tertiary referral hospitals in Boston. The primary outcome was diagnosis of CRC. We examined the proportion of patients undergoing a colonoscopy within 36 months before a diagnosis of CRC or at the end of the follow-up period, excluding colonoscopies performed within 6 months before a diagnosis of CRC, to avoid inclusion of prevalent cancers. Multivariate logistic regression was performed, adjusting for plausible confounders. Results One hundred fifty-four patients developed CRC. The incidence of CRC among patients without a recent colonoscopy (2.7%) was significantly higher than among patients with a recent colonoscopy (1.6%) (odds ratio [OR], 0.56; 95% confidence interval, 0.39−0.80). This difference persisted in multivariate analysis (OR, 0.65; 95% CI, 0.45−0.93) and was robust when adjusted for a range of assumptions in sensitivity analyses. Among patients with CRC, a colonoscopy within 6−36 months before diagnosis was associated with reduced mortality (OR, 0.34; 95% CI 0.12−0.95). Conclusions Recent colonoscopy (within 36 months) is associated with a reduced incidence of CRC in patients with IBD, and lower mortality in those diagnosed with CRC

Risk Factors for Colorectal Cancer

“…These results are corroborated by a number of both prospective and retrospective studies in multiple setting and countries [11][12][13][14]. Additionally, colonoscopy in patients with IBD has also been shown to reduce CRC risk (OR =0.56, 95%CI 0.39-80) and all-cause mortality (OR=0.34, 95% CI =0.12-0.95), suggesting that CRC in this patient population is derived from adenomas similar to the general population [15].…”

DNA Methylation and Mutation of Small Colonic Neoplasms in Ulcerative Colitis and Crohnʼs Colitis

“…CRC detected at surveillance may be at earlier stage, and therefore have a better prognosis than when presenting symptomatically(10–12), and evidence suggests that regular colonoscopic surveillance reduces CRC mortality in patients with IBD. (11, 13) Despite these encouraging data, patient compliance with surveillance colonoscopy is poor, even among those at highest risk. (14) Additionally, 17–30% of CRC diagnosed in large IBD surveillance cohorts were interval cancers.…”

Use of an α-Glucosidase Inhibitor and the Risk of Colorectal Cancer in Patients With Diabetes: A Nationwide, Population-Based Cohort Study

“…Surveillance colonoscopy in the current study was defined as undergoing a colonoscopy within 36 months before colorectal cancer diagnosis or the end of follow-up. To avoid influencing the diagnosis of colorectal cancer, colonoscopy performed within 6 months before the diagnosis was excluded (24). At least 3 years of care data in the current cohort were required to ensure a similar period for collecting colonoscopy data.…”