Carolina: Breast cancer rates among women under 50 have increased more than 15 percent in the past two decades, and experts say the increase is almost entirely due to estrogen receptor-positive breast cancer, a tumor A subtype that requires the hormone estrogen to grow.
Estrogen receptor breast cancer is the most common type of breast cancer in women of all age groups.
This particular type of breast cancer is especially on the rise among younger women, so some doctors suspect it has to do with more women in the U.S. starting their periods earlier and having their first child later.
Dr. Alexandra Thomas, a medical oncologist at Duke Health, said women are exposed to more estrogen as they age. That’s probably a big reason, but we don’t know why we’re seeing more early menarche.
He also said that a number of factors are likely behind the increase, including obesity, alcohol use, genetics and some hormonal birth control, but the role of early puberty in breast cancer risk is gaining attention.
