This phase II trial evaluates tamoxifen, with or without omega-3 fatty acids, for reducing risk of breast cancer among postmenopausal and overweight or obese women who are at increased risk of developing breast cancer. Tamoxifen is a selective estrogen receptor modulator. It works by blocking the effects of the hormone estrogen in the breast. Tamoxifen is approved by the Food and Drug Administration for prevention of breast cancer in women at increased risk. Omega-3 fatty acids have been shown to decrease the amount of fats made in the liver. Omega-3 fatty acids may work to prevent cancer in overweight or obese individuals. Tamoxifen with or without omega-3 fatty acids may be effective at reducing risk of breast cancer among women who are postmenopausal, overweight or obese, and at increased risk.
Age 45 - 74
Postmenopausal female
Postmenopausal is defined as either
Prior removal of the ovaries, or if ovaries intact amenorrhea for >= 12 months and not on any form of contraception, or
Bilateral breast implants (danger of implant puncture with RPFNA)
Prior invasive breast cancer
Prior invasive uterine cancer
Other prior invasive cancer and haven't completed cancer related therapy or with evidence of disease (other than non-melanoma skin cancer) within the past 2 years