Breast Cancer Facts: Risk Factors
While any woman is at risk of developing breast cancer, some women are with more risk factors than others. There are certain things that may increase your risk of breast cancer. Some of these risk factors
are proven, and others are uncertain.
- Previous Breast Cancer: If you have had breast cancer before, you are at a higher risk of developing it again. About 10%-15% of women who have had breast cancer will develop breast cancer again within 20 years.
- Family History of Breast Cancer: If you have a mother, sister or daughter who has had breast cancer, you may be two to four times more likely to develop breast cancer. The risk is higher if the relative had breast cancer before menopause or had cancer in both breasts, and if breast cancer has occurred in several generations.
- Genetic Factors: BRCA1 and BRCA2 Genes: These genes, called tumor suppressor genes
, help regulate cell growth. If you have mutations
(changes) in these genes, you may be at an increased risk of breast cancer. An estimated 5%-10% of breast cancer cases are caused by these gene mutations.
- Age: Your risk of breast cancer increases with age. Approximately 80% of breast cancer cases occur in women older than age 50.
- Reproductive History: If you have never been pregnant or never had a baby, you may have an increased risk of breast cancer. If you had your first baby after age 30, you may be at an increased risk of breast cancer. In addition, if you had your first menstrual period before age 12, or if you developed menopause late, you may have an increased risk of breast cancer.
- Benign Breast Conditions: Certain benign
breast conditions may increase your risk of breast cancer, especially a condition called hyperplasia
. Hyperplasia causes an overproduction of breast cells. If these extra cells are abnormal, the risk increases even more, especially if you have a family history of breast cancer.
- Hormone Replacement Therapy (HRT): Some studies have shown that receiving hormone replacement therapy
(HRT) for a long time may increase the risk of breast cancer. If you receive HRT, you should discuss the benefits and potential risks with your doctor.
- Lifestyle and Environmental Factors: Researchers continuously study lifestyle and environmental factors that may increase the risk of breast cancer, including smoking, eating a diet high in fat and low in fiber, and being exposed to environmental pollutants. More studies are needed to determine if such factors do increase the risk of breast cancer; however, it is always recommended that you try and maintain a healthy lifestyle that includes not smoking, maintaining a healthy diet and exercising regularly.
Reducing Your Risk of Breast Cancer
There is no proven way to prevent breast cancer. However, there are things you may be able to do to reduce your risk of breast cancer. While lifestyle changes have not been proven to reduce the risk of breast cancer, some studies have shown that maintaining a healthy body weight and being physically active may help reduce your risk of breast cancer.
Women at high risk of breast cancer also may consider a treatment called chemoprevention
. This involves taking an antiestrogen drug
to help prevent new breast tumors
from forming. This drug does have side effects
so it is important to talk to your doctor about the benefits and potential risks of chemoprevention.
Since there is no sure way to prevent breast cancer, it is important to get regular screening to try and catch breast cancer early. Learn more about early detection on our Breast Cancer Facts: Screening And Early Detection page.
