title: The anatomical distribution of colorectal cancer in Korea: evaluation of the incidence of proximal and distal lesions and synchronous adenomas.
abstract: OBJECTIVE
  The incidence of colorectal cancer throughout the Republic of Korea has been rising over the last 25 years. The change in incidence is supposed to be due to the westernized life style. We evaluated the anatomical distribution of colorectal cancer and the properties of synchronous adenomatous polyps in the Korean population which were known to be different from those in Western countries.
  
  
  METHODS
  From January 1997 to December 2006, 896 cases of colorectal cancer were reviewed retrospectively.
  
  
  RESULTS
  A total of 25.1% were proximally located cancer with a modest female predominance (odds ratio 1.5). Synchronous adenomatous lesions were accompanied in 31.9% of all colorectal cancer cases. In the distal colorectal cancer patients, 18.8% had proximally located synchronous adenomas. In those with proximal colon cancer, only 20.5% of patients had distally located adenomas. The likelihood of a proximal colon cancer without distal sentinel lesions was higher in females (odds ratio 3.0).
  
  
  CONCLUSIONS
  There has been a steep rise in the incidence of colorectal cancer in Korea and distal colon cancer is more prevalent than in Western countries. However, as over 20% of proximal colon cancers can exist without distal colonic synchronous or sentinel lesions, a total colonoscopic examination should be considered first in surveillance.
authors.affiliation: Department of Internal Medicine, the Catholic University of Korea College of Medicine, Seoul, Korea.
authors.forename: Dae Young
authors.initials: DY
authors.lastname: Cheung
authors.forename: Tae Ho
authors.initials: TH
authors.lastname: Kim
authors.forename: Chang Whan
authors.initials: CW
authors.lastname: Kim
authors.forename: Jin Il
authors.initials: JI
authors.lastname: Kim
authors.forename: Se Hyun
authors.initials: SH
authors.lastname: Cho
authors.forename: Soo-Heon
authors.initials: SH
authors.lastname: Park
authors.forename: Joon-Yeol
authors.initials: JY
authors.lastname: Han
authors.forename: Jae Kwang
authors.initials: JK
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology; D002288:Adenocarcinoma, Mucinous / Q000453:epidemiology / Q000473:pathology; D018256:Adenomatous Polyps / Q000453:epidemiology / Q000473:pathology*; D000328:Adult; D000368:Aged; D018279:Carcinoma, Signet Ring Cell / Q000453:epidemiology / Q000473:pathology; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000473:pathology*; D005260:Female; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000453:epidemiology / Q000473:pathology*; D016017:Odds Ratio; D012189:Retrospective Studies; D012737:Sex Factors