Early Onset Breast Cancer is on the Rise in Younger Women
- by Natasha Hobley
- Published
- Environment
Data from recent years shows that early onset breast cancer is on the rise, particularly in younger women under age 50. The breast cancer incidence rate is increasing at 1.4 percent annually in those under the age of 50, compared to 0.7 percent for women over the age of 50.1
While breast cancer incidence in younger women is still low—about 49 per 100,000 in 2019— experts consider the sharp increase a “deeply concerning trend,” particularly since women under 40 are nearly 40 percent more likely to die from their breast cancer than women over 40.2
Estrogen Fuels Breast Cancer Surge
A study published in the Journal of the American Medical Association (JAMA) found another interesting trend in breast cancer data: the surge is driven almost entirely by cancerous growths that are fueled by estrogen— also known as estrogen-receptor positive tumors. These tumors have surface proteins that bind to estrogen and fuel the tumor growth.3
The researchers also found higher rates of breast cancer among Black women, especially among those ages 20 to 29.3
Differences in breast cancer risk by year of birth were also found. Senior author of the study Adetunji T. Toriola, MD, PhD, MPH said the most dramatic difference was a greater than 20 percent increased risk of breast cancer among women born in 1990 compared to women born in 1955.3
Hormonal Contraceptives Linked to 20 to 30 Percent Increase in Breast Cancer
While doctors are stumped by the surge in cancer rates among younger generations, existing studies from around the world show that the use of any type of hormonal contraceptive has been shown to be linked to an increased risk of breast cancer.
An analysis of almost 10,000 women found that use of progestogen-only hormonal contraceptives is associated with a 20 to 30 percent higher risk of breast cancer compared to women who have never used hormonal birth control. Previous studies have shown that the use of combined estrogen and progestogen contraceptive pills is also associated with an increase in breast cancer risk, but the risk is significantly smaller and declines after stopping use.4
An estimated 151 million women of reproductive age use oral hormonal contraceptives worldwide. This number does not include long-acting reversible contraceptive (LARC) methods such as the patch or some types of intrauterine devices (IUDs) which are hormone-containing forms of birth control.5
Other factors that may be linked to the increased breast cancer rates in the younger generations are obesity, processed foods, delaying the onset of childbearing, and endocrine disrupters such as bisphenol A (BPA) commonly found in plastics.
If you would like to receive an e-mail notice of the most recent articles published in The Vaccine Reaction each week, click here.
Click here to view References: