title: Advanced synchronous adenoma but not simple adenoma predicts the future development of metachronous neoplasia in patients with resected colorectal cancer.
abstract: BACKGROUND
  Patients with resected colorectal cancer remain at a high risk for developing metachronous neoplasia in the remnant colorectum. The aim of this study was to identify baseline clinical and colonoscopic features predictive of metachronous neoplasia after curative resection of colorectal cancer.
  
  
  METHODS
  The baseline clinical and colonoscopic data and follow-up details of 503 patients who had colonoscopic surveillance after curative colorectal resection between January 2000 and October 2005 in a single tertiary institution were analyzed. Univariate and multivariate analyses were done to identify risk factors for metachronous adenoma.
  
  
  RESULTS
  Metachronous adenomas were diagnosed in 176 patients (35.0%) and advanced adenomas in 39 (7.8%) during the follow-up period (35.7+/-20.9 mo). Among the clinical and colonoscopic factors at baseline, advanced age (> or = 60 y) (odds ratio (OR)=3.64; 95% confidence intervals (CI), 1.55-8.52), the presence of advanced synchronous adenoma (OR=4.38; 95% CI, 1.77-10.85), and longer total follow-up period (OR=1.03; 95% CI, 1.01-1.04) were independently correlated with developing advanced metachronous adenoma. Patients who had synchronous tubular adenoma without advanced features at baseline were not found to have an increased risk for future development of advanced metachronous adenoma compared with those in the synchronous adenoma-free group (OR=1.75; 95% CI, 0.69-4.43, P=0.650).
  
  
  CONCLUSIONS
  Our data showed that patients with advanced synchronous adenoma at baseline were identified to have an increased risk of advanced metachronous neoplasia during a longer follow-up period but those with tubular adenoma without advanced features at baseline were not.
authors.affiliation: Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Chang Mo
authors.initials: CM
authors.lastname: Moon
authors.forename: Jae Hee
authors.initials: JH
authors.lastname: Cheon
authors.forename: Eun Hee
authors.initials: EH
authors.lastname: Choi
authors.forename: Eun Soo
authors.initials: ES
authors.lastname: Kim
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Park
authors.forename: Song Yi
authors.initials: SY
authors.lastname: Han
authors.forename: Duk Hwan
authors.initials: DH
authors.lastname: Kim
authors.forename: Tae Il
authors.initials: TI
authors.lastname: Kim
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Kim
mesh_terms: D000236:Adenoma / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000473:pathology; D012306:Risk; D012307:Risk Factors; D013997:Time Factors