title: The clinical significance in healthy men of the association between obesity related plasma hemodilution and tumor marker concentration.
abstract: OBJECTIVE
  We investigated the association between body mass index and the concentration of tumor markers including carcinoembryonic antigen, alpha-fetoprotein, the carbohydrate antigen 19-9 and prostate specific antigen, as well as the association between body mass index changes and tumor marker concentration changes in a population of healthy men.
  
  
  METHODS
  We evaluated data on 8,776 men screened for tumor markers (carcinoembryonic antigen, alpha-fetoprotein, carbohydrate antigen 19-9 and prostate specific antigen) at least 3 times annually during an annual examination from 2001 to 2007. We assessed the tumor marker test findings for a trend in the age, alanine aminotransferase and creatinine adjusted tumor marker concentration by body mass index. We used multivariate regression analysis to determine whether a change in body mass index was associated with a tumor marker concentration change over time using calculated tumor markers, body mass index, creatinine and alanine aminotransferase concentration change per year.
  
  
  RESULTS
  After adjusting for age, creatinine and alanine aminotransferase a higher body mass index was associated with lower prostate specific antigen (p for trend <0.001), carcinoembryonic antigen (p for trend <0.001) and carbohydrate antigen 19-9 (p for trend <0.001). On multivariate regression analysis each 1 kg/m(2) of body mass index gain per year was associated with a -0.011 ng/ml change in prostate specific antigen concentration, a -0.030 ng/ml change in carcinoembryonic antigen concentration and a -0.192 IU/ml change in carbohydrate antigen 19-9 concentration per year.
  
  
  CONCLUSIONS
  In this cohort of healthy men hemodilution from increased plasma volume may be responsible for the observed decreased tumor marker concentration in men with a higher body mass index. In addition, an increase in body mass index may predict a lower tumor marker concentration in an individual.
authors.affiliation: Department of Urology, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: In Ho
authors.initials: IH
authors.lastname: Chang
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Ahn
authors.forename: June Hyun
authors.initials: JH
authors.lastname: Han
authors.forename: Tae-Hyoung
authors.initials: TH
authors.lastname: Kim
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Soon Chul
authors.initials: SC
authors.lastname: Myung
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D014408:Biomarkers, Tumor / Q000097:blood*; D001810:Blood Volume; D015992:Body Mass Index; D018395:CA-19-9 Antigen / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000097:blood; D015331:Cohort Studies; D055088:Early Detection of Cancer; D006438:Hemodilution; D006801:Humans; D016014:Linear Models; D008297:Male; D008403:Mass Screening; D015999:Multivariate Analysis; D009765:Obesity / Q000097:blood*; D017430:Prostate-Specific Antigen / Q000097:blood; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D000509:alpha-Fetoproteins / Q000032:analysis
chemical_list: D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen; D000509:alpha-Fetoproteins; D017430:Prostate-Specific Antigen