The epidemiology of CA-125 in women without evidence of ovarian cancer in the Prostate, Lung, Colorectal and Ovarian Cancer (PLCO) Screening Trial

Gynecol Oncol. 2008 Sep;110(3):383-9. doi: 10.1016/j.ygyno.2008.05.006. Epub 2008 Jun 30.


Objective: To determine the epidemiology of CA-125 in women without ovarian cancer.

Methods: We analyzed demographic, medical and lifestyle characteristics related to CA-125, measured using the Centocor CA-125II RIA assay, among 25,608 multi-ethnic U.S. women aged 55-74 years enrolled in a cancer screening trial and found to have no evidence of ovarian cancer.

Results: Mean CA-125 level was 11.9 U/ml (SD 8.3); median 10.0 U/ml, interquartile range 8.0-14.0. High levels, using the clinical cut point of >or=35 U/ml, were associated with increased age (p<0.001) and former smoking (p<0.021), while hysterectomy and obesity were protective (p<0.001). Mean levels were higher with increasing age (p<0.001), ever use of hormone therapy (p<0.001), former smoking (p<0.017) and history of breast cancer (p<0.002), but lower (p<0.001) with non-White status, previous hysterectomy, current smoking, and obesity. Current hormone therapy use was not associated with CA-125 in women without a uterus.

Conclusion: In post-menopausal women without ovarian cancer, CA-125 level is influenced by a number of factors, including race/ethnicity, age, hysterectomy, smoking history and obesity.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Age Factors
  • Aged
  • CA-125 Antigen / blood*
  • Ethnicity
  • Female
  • Humans
  • Mass Screening
  • Middle Aged
  • Ovarian Neoplasms / blood*
  • Ovarian Neoplasms / epidemiology*
  • Socioeconomic Factors


  • CA-125 Antigen