title: Clinicopathological characteristics of colon cancer diagnosed at primary health care institutions.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the clinicopathologic characteristics of colon cancers detected at the SOK Sokpeynhan Internal Medical Network, a nationwide system of primary health care institutions.
  
  
  METHODS
  We analyzed 579 colon cancer patients diagnosed using colonoscopy at the SOK network from January 2011 through December 2012. Cancers from the rectum to the splenic flexure were classified as left colon cancer. Patients over 65 were classified as senior.
  
  
  RESULTS
  The mean age (±SD) of subjects was 60.9±10.5 years and 61.1% were men. More than one quarter (28.2%) of patients were asymptomatic. The prevalence of left colon cancer was higher (77.9%) than that for right colon cancer. The most frequent macroscopic and histologic types were depressed (58.9%) and moderately differentiated adenocarcinoma (52.2%), respectively. Asymptomatic subjects displayed protruding or well differentiated adenocarcinoma, while symptomatic patients were more likely to display depressed or moderately differentiated adenocarcinoma (P<0.05). The mean age of the right colon cancer group was higher than that for the left colon cancer group (P<0.05). Among symptomatic patients, the most frequent symptoms were bloody stool for patients with left colon cancer and abdominal discomfort for patients with right colon cancer (P<0.05). The prevalence of depressed cancer was higher in older subjects as compared to younger subjects (P<0.05). The prevalence of right colon cancer tended to increase with age, although this difference did not achieve statistical significance (P>0.05).
  
  
  CONCLUSIONS
  Study results indicated an increase of colon cancer amongst younger demographics in recent years. The effectiveness of colonoscopy screening was also evident, as asymptomatic patients demonstrated frequent findings of well differentiated adenocarcinomas. Study results also suggested a need for closer examination of older patients, as right colon cancer tended to increase with age.
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Seoul, Korea.
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Park
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Seoul, Korea.
authors.forename: Chi Wook
authors.initials: CW
authors.lastname: Song
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Seoul, Korea.
authors.forename: Yun Bae
authors.initials: YB
authors.lastname: Kim
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Seoul, Korea.
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Kim
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Seoul, Korea.
authors.forename: Hwang Rae
authors.initials: HR
authors.lastname: Chun
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Busan, Korea.
authors.forename: Jung Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Incheon, Korea.
authors.forename: Won Jong
authors.initials: WJ
authors.lastname: Seol
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Incheon Gyeyang, Korea.
authors.forename: Hyung Sun
authors.initials: HS
authors.lastname: Yoon
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Daegu, Korea.
authors.forename: Myung Kwon
authors.initials: MK
authors.lastname: Lee
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Deagu Sangin, Korea.
authors.forename: Jong Hyup
authors.initials: JH
authors.lastname: Lee
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Suwon, Korea.
authors.forename: Choon Sang
authors.initials: CS
authors.lastname: Bhang
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Ulsan, Korea.
authors.forename: Jae Hyung
authors.initials: JH
authors.lastname: Park
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Cheonan, Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Park
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Pohang, Korea.
authors.forename: Byung Hun
authors.initials: BH
authors.lastname: Do
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Gumi, Korea.
authors.forename: Young Dae
authors.initials: YD
authors.lastname: Park
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Daejeon Dunsan, Korea.
authors.forename: Sang Jeong
authors.initials: SJ
authors.lastname: Yoon
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Seodaejeon, Korea.
authors.forename: Chan Wook
authors.initials: CW
authors.lastname: Park
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Anyang, Korea.
authors.forename: Su Mi
authors.initials: SM
authors.lastname: Yoon
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Uijeongbu, Korea.
authors.forename: Jong Hwan
authors.initials: JH
authors.lastname: Choi
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Pyeongtaek, Korea.
authors.forename: Ki Chul
authors.initials: KC
authors.lastname: Shin
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Seongnam, Korea.
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Ko
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Ilsan, Korea.
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: SOK Sokpeynhan Internal Medical Network, Bucheon, Korea.
authors.forename: Dong Choon
authors.initials: DC
authors.lastname: Seol
keywords: Colonic neoplasms; Population characteristics; Primary health care