1. Breast Cancer Risk Factors

2. What causes breast cancer? • No one knows why some women develop breast cancer and others do not • However, research has shown that women with certain risk factors are more likely to develop a breast cancer • Risk factors are characteristics or behaviors that increase the possibility of developing a disease

3. Risk factors for breast cancer • The greatest risk factors for breast cancer are sex and age • Men do get breast cancer, but it is extremely rare; breast cancer primarily affects women • The chance of developing a breast cancer increases the older a woman gets • Breast cancer is not common in women before menopause • Most cases of breast cancer occur in patients over the age of 60

4. Personal history of breast cancer – a woman who has had breast cancer in one breast has an increased risk of developing cancer in the other breast • Family history – having relatives with cancer increases a person’s risk of developing cancer Do all women with a family history of cancer develop breast cancer? No. Many women with known risk factors do not get breast cancer. In fact, most women with breast cancer have no family history of the disease.

5. Additional risk factors for breast cancer • Breast changes – the presence of some abnormal cells in the breast (either atypical hyperplasia or lobular carcinoma in situ (LCIS)) increases the risk of breast cancer • Breast density – women with dense breast tissue are at an increased risk • Race – breast cancer is diagnosed more often in white women than in Latina, Asian, or African American women

6. Genetic mutations – mutations in genes such as BRCA1 and BRCA2 increase a woman’s risk of developing breast cancer • Being overweight or obese after menopause • Lack of physical activity – women who are inactive throughout their life may have an increased risk of breast cancer • Drinking alcohol – studies suggest that the more alcohol a woman drinks, the greater her risk of breast cancer

7. Reproductive and menstrual history • The older a woman is when she has her first child, the greater her risk of breast cancer • Women who had their first menstrual period before age 12 are at increased risk • Women who went through menopause after age 55 have a higher risk • Women who never had children have a higher risk • Women who take hormone therapy after menopause appear to have an increased risk of breast cancer

8. Additional risk factors • Radiation therapy to the chest • women who had radiation before age 30 are at an increased risk of breast cancer • studies show that the younger a woman was when she received radiation treatment, the higher her risk of breast cancer later in life • Taking DES (diethylstilbestrol) • DES was given to some pregnant women in the US between 1940 and 1971 • Women who took DES may have a slightly increased risk of breast cancer

9. Reducing Risk • Some of the risk factors for breast cancer are out of the control of the individual • What risk factors can a person control? • Age, sex, race, personal and family history, breast changes, breast density, genetic mutation, radiation therapy • Physical activity, weight, alcohol consumption

10. Resources • What You Need to Know About Breast Cancer, National Cancer Institute • Breast Cancer Prevention, National Cancer Institute http://www.cancer.gov/cancertopics/pdq/prevention/breast/Patient/page3 • What are the risk factors for breast cancer? American Cancer Society http://www.cancer.org/docroot/CRI/content/CRI_2_4_2X_What_are_the_risk_factors_for_breast_cancer_5.asp