CALGB 70806- Vitamin D and Breast Cancer Biomarkers
This is a multicenter study. Patients are stratified according to baseline vitamin D (sufficient [>= 30 ng/mL or >= 75 mmol/L] vs insufficient [< 30 ng/mL or < 75 mmol/L]) and institutional random periareolar fine-needle aspiration (RPFNA) status (performs RPFNA vs does not perform RPFNA). Patients are randomized to 1 of 2 treatment arms.
[?]Arm I: Patients receive oral placebo once daily for 12 months.
[?]Arm II: Patients receive oral vitamin D (2000 IU) once daily for 12 months. Tissue and blood samples are collected at baseline and at 12 months for laboratory biomarker analysis. Patients also complete questionnaires at baseline and at 12 months.
Premenopausal women 55 years of age or younger with regular menstrual cycles (at least four cycles in the last six months).
Women with fewer than 4 menses in the last 6 months or who have had a hysterectomy with ovaries intact will be considered premenopausal if FSH level < 20.
Women with breast density >= 25% (
* scattered fibroglandular densities
* or greater) are eligible.