title: The levels of carbohydrate antigen 19-9 are associated with gender and age in Chinese population.
abstract: BACKGROUND
  CA 19-9 is one of the most frequently used biomarkers for tumors.
  
  
  METHODS
  We analyzed the influential factors of the Carbohydrate Antigen 19-9 (CA 19-9) levels in Chinese general population to better interpret the results of the CA 19-9 screening tests. 36,924 apparently healthy individuals and 1,335 patients with gastrointestinal (GI) tumors were involved in this study. Serum CA 19-9 levels were measured using a Roche Cobas E601.
  
  
  RESULTS
  The serum CA 19-9 levels in apparently healthy individuals were correlated with age and gender. Its level was positively correlated with the age of males, while it showed a V-shape curve in female populations. This effect could be due to sex hormones, such as prolactin, which were found to have a negative effect on the level of CA 19-9 in the present study.
  
  
  CONCLUSIONS
  Our data indicates that gender and age could affect the CA19-9 serum level. We can set up different cut-off values according to the patient's gender and age, which can help us to get a more individualized representation in different populations.
authors.affiliation: Clinical Laboratory, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016, China.
authors.forename: Yan-Zhong
authors.initials: YZ
authors.lastname: Wang
authors.forename: Yan-Wen
authors.initials: YW
authors.lastname: Zhou
authors.forename: Xin-You
authors.initials: XY
authors.lastname: Xie
authors.forename: Gui-Ling
authors.initials: GL
authors.lastname: Li
authors.forename: Xiu-Hong
authors.initials: XH
authors.lastname: Wang
authors.forename: Feng-Ying
authors.initials: FY
authors.lastname: Li
authors.forename: Zhi-An
authors.initials: ZA
authors.lastname: Le
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Zhong
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood*; D002681:China; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen