Abstract

PIP: Current epidemiologic data from research on the association between combined oral contraceptives (OCs) and breast cancer show that longterm OC use does not significantly increase the risk of developing breast cancer after age 45, but may indeed protect against postmenopausal breast cancer. Yet, older studies with high dose OCs demonstrate a somewhat increased risk (relative risk = 1.5) for young women who have used OCs early and for at least 4 years. Nevertheless, the lack of association even holds true for women with a family history of breast cancer or for those who have benign breast disease. Studies should continue, however, since the OC user cohort is aging and to increase the statistical power of current studies. Standard hormonal replacement therapy consists of a progestin and estrogen. Addition of progestin prevents the risk of endometrial cancer. Some research indicates that it may also protect against breast cancer. However, research from Uppsala, Sweden, suggests that combined estrogen-progestin treatment slightly, but not significantly, increases the breast cancer risk. Further research and longer duration of hormonal replacement therapy should provide clinicians with more information about the breast cancer risk. Individual physicians should inform their patients about concerns raised by the research about hormones and breast cancer, but should be optimistic since the possible risk has not been proven. Some medical associations have already developed guidelines for physicians and included them into continuing medical education programs.