OBJECTIVES:
Primary
* Determine whether breast density, as measured by digital mammography, decreases in premenopausal women receiving tamoxifen for breast cancer or for breast cancer risk reduction.
* Determine whether breast density, as determined by a trained mammographer, decreases in patients treated with this drug.
* Correlate tamoxifen-induced symptoms in estrogen target tissue with change in salivary steroids in patients treated with this drug.
Secondary
* Determine the effect of this drug on salivary steroids in regularly cycling and amenorrheic patients.
* Correlate changes in breast density with tamoxifen-induced alterations in sex steroid levels, as measured in the saliva, of patients treated with this drug.
OUTLINE: Patients receive oral tamoxifen once daily. Treatment continues for 5 years in the absence of disease metastasis (patients with known breast cancer) or a diagnosis of breast cancer (patients undergoing risk reduction).
Patients undergo mammography to determine breast density at baseline, at 6 and 12 months, and then annually for 4 years. Patients also collect daily salivary samples during the 30-day periods surrounding the imaging studies to measure salivary estradiol and progesterone levels. The results of the salivary hormone studies are correlated with density changes at study completion.
PROJECTED ACCRUAL: A total of 100 patients will be accrued for this study.