The anatomical distribution of colorectal cancer in Korea: evaluation of the incidence of proximal and distal lesions and synchronous adenomas.
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.
Cheung
Dae Young
DY
Department of Internal Medicine, the Catholic University of Korea College of Medicine, Seoul, Korea.
Kim
Tae Ho
TH
Kim
Chang Whan
CW
Kim
Jin Il
JI
Cho
Se Hyun
SH
Park
Soo-Heon
SH
Han
Joon-Yeol
JY
Kim
Jae Kwang
JK
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