title: Should a colonoscopy be recommended for healthy individuals with increased carcinoembryonic antigen levels? A case-control study.
abstract: OBJECTIVE
  Despite the limitations of screening or early diagnosis of colorectal cancers (CRC), carcinoembryonic antigen (CEA) is frequently measured in practice and during health promotion programs. The aim of this study was to evaluate the role of colonoscopy in healthy individuals with elevated CEA levels.
  
  
  METHODS
  From January 2003 to November 2008, 117,731 healthy persons underwent an opportunistic screening program in two health promotion centers; 1,497 subjects (1.3%) showed an elevated CEA level (>5 ng/ml). Among them, 174 patients were recruited to undergo a colonoscopy to determine if colorectal malignancies were present. A total of 372 age- and sex-matched persons were selected as controls from among the healthy subjects who had a normal level of CEA and had received surveillance colonoscopy. The primary outcome was the incidences of CRC in elevated CEA and normal CEA groups. The secondary outcome was the predictive factors of CRC in the elevated CEA group.
  
  
  RESULTS
  The incidence of CRC was higher in the group with higher CEA-levels than in the group with normal CEA levels (4.6 vs. 1.3%; P=0.031). In the CEA-elevated group, patients with CRCs were diagnosed at more advanced stages than were those in the CEA-normal group. The incidence of colorectal polyps was not different between the two groups. In the CEA-elevated group, anemia was an independent predictive factor of CRCs by multivariate analysis (P=0.002).
  
  
  CONCLUSIONS
  Anemia itself is not a predictive factor of CRC in the entire population, but is an independent predictive factor of CRC in healthy individuals with an elevated level of CEA. Therefore, colonoscopy should be recommended for healthy subjects with an elevated level of CEA accompanied with anemia in the absence of other adenocarcinomas to evaluate the presence of colorectal malignancy.
authors.affiliation: Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, and Sanggye Paik Hospital, 250 Seongsanno, Seodaemun-gu, Seoul, 120-752, Republic of Korea.
authors.forename: Jin Ha
authors.initials: JH
authors.lastname: Lee
authors.forename: Sung Pil
authors.initials: SP
authors.lastname: Hong
authors.forename: Tae Joo
authors.initials: TJ
authors.lastname: Jeon
authors.forename: Gun-Hi
authors.initials: GH
authors.lastname: Kang
authors.forename: Won-Choong
authors.initials: WC
authors.lastname: Choi
authors.forename: Soung Min
authors.initials: SM
authors.lastname: Jeon
authors.forename: Chang Mo
authors.initials: CM
authors.lastname: Moon
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Park
authors.forename: Jae Hee
authors.initials: JH
authors.lastname: Cheon
authors.forename: Tae Il
authors.initials: TI
authors.lastname: Kim
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000453:epidemiology; D000328:Adult; D000368:Aged; D000740:Anemia / Q000175:diagnosis* / Q000453:epidemiology; D014408:Biomarkers, Tumor / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000097:blood*; D016022:Case-Control Studies; D003111:Colonic Polyps / Q000175:diagnosis* / Q000453:epidemiology; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D055088:Early Detection of Cancer / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009765:Obesity
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen