title: Rate of early/missed colorectal cancers after colonoscopy in older patients with or without inflammatory bowel disease in the United States.
abstract: OBJECTIVE
  Patients with inflammatory bowel disease (IBD) have an increased risk for colorectal cancer (CRC). Previous studies on early/missed CRCs after colonoscopy excluded IBD patients. The aim of this study was to compare the rate of early/missed CRCs after colonoscopy among IBD and non-IBD patients, and identify factors associated with early/missed CRCs.
  
  
  METHODS
  All patients in the Surveillance, Epidemiology and End-Results Medicare-linked database who were 67 years or older at colonoscopy during 1998-2005 and those who were subsequently diagnosed with CRC within 36 months were identified. CRCs diagnosed within 6 months of colonoscopy were categorized as detected CRCs; CRCs diagnosed 6-36 months after colonoscopy were categorized as early/missed CRCs. The rate of early/missed CRCs was calculated as number of early/missed CRCs divided by number of detected and early/missed CRCs. The χ(2) test and multivariate logistic regression were used in statistical analysis.
  
  
  RESULTS
  Of 55,008 CRC patients (304 Crohn's disease; 544 ulcerative colitis (UC)), the rate of early/missed CRCs was 5.8% for non-IBD patients, 15.1% for Crohn's, and 15.8% for UC (P<0.001). Compared with older non-IBD patients, early/missed CRCs among older IBD patients were less likely right-sided (both P<0.05). In multivariate logistic regression, the risk of early/missed CRCs was three times as high for IBD patients (Crohn's odds ratio (OR), 3.07; 95% confidence interval (CI) 2.23-4.21; UC OR, 3.05; 95% CI, 2.44-3.81). Sensitivity analyses confirmed the robustness of this finding.
  
  
  CONCLUSIONS
  Older IBD patients had a higher rate of early/missed CRCs after colonoscopy. Our finding supports intensive surveillance colonoscopy for older IBD patients as recommended by guidelines.
authors.affiliation: Division of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, Florida, USA. wang-yize@cooperhealth.edu
authors.forename: Yize R
authors.initials: YR
authors.lastname: Wang
authors.forename: John R
authors.initials: JR
authors.lastname: Cangemi
authors.forename: Edward V
authors.initials: EV
authors.lastname: Loftus
authors.forename: Michael F
authors.initials: MF
authors.lastname: Picco
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D055088:Early Detection of Cancer / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications* / Q000453:epidemiology; D008297:Male; D018426:SEER Program; D012680:Sensitivity and Specificity; D014481:United States / Q000453:epidemiology