Dense Breasts, Hormone Levels Are Two Separate, Independent Risk Factors For Breast Cancer
Breast Cancer Risk
The density of a woman's breast tissue and her level of sex hormones are two strong and independent risk factors for breast cancer, according to a team of researchers from Harvard and Georgetown universities. The finding dispels the common belief that the risk associated with dense breasts merely reflects the same risk associated with high levels of circulating sex hormones, they say.
Their study, published in the August 1 issue of the Journal of the National Cancer Institute, found that the relative risk of developing breast cancer in post-menopausal woman with dense breasts was 400 percent higher than in women with fatty, non-dense breast tissue, and that high versus low levels of hormones (estrogen and testosterone) increased the relative risk by 200 percent. Adjusting for a woman