Why does taking estrogen increase the risk of false-positive mammograms?
Estrogen stimulates the growth and proliferation of normal (as well as abnormal) breast tissue. After menopause, in the absence of estrogen, the breasts undergo atrophy of the glandular and fibrous tissues. The relative amount of fatty tissue increases. Mammography is especially suited for examining these low-density post-menopausal breasts, which allow good penetration of the x-ray beam. Taking estrogen replacement therapy partially reverses (or prevents) these menopausal changes, resulting in denser breast tissue which produces more complex x-ray shadows. These shadows can sometimes mimic those produced by breast cancers.
Related Questions
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- What effects of hormone replacement therapy are there for cardiovascular disease? Does taking HRT increase one’s risk?
- Why does taking estrogen increase the risk of false-positive mammograms?
