Title of Collaborative Activity: |
Circulating Estrogens, Androgens, and Progestogens and Risk of Breast Cancer in the PLCO Cohort |
Description of Collaborative Activity: |
In a stratified cohort study of breast cancer in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO), restricted to postmenopausal women not on menopausal hormone therapy, researchers are using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay recently developed by the Centers for Disease Control and Prevention (CDC) to assess pre-diagnostic circulating levels of the endogenous steroid hormones believed to be involved in breast cancer etiology. Although it is known that endogenous hormones play a critical role in the etiology of breast cancer, the interrelationships among estrogens, androgens, and progesterone in determining risk are not well understood. |