Risk Factors
Risk Factors for Developing Breast Cancer
A risk factor is anything that impacts an individual’s chance of getting a disease, in this case of getting breast cancer. There are things that put you at risk which are in your control and you can change, and there are things which put you at risk which are not in your control and you cannot change.
Risk factors associated with breast cancer, including those which are unchangeable, and those which are lifestyle related.
- Increasing age
- Female sex
- Menstrual factors
- Early age at menarche (onset of menses before age 12 yr)
- Older age at menopause (onset beyond age 55 yr)
- Nulliparity
- Family history of breast cancer
- Genetic predisposition (BRCA1 and BRCA2 mutation carriers)
- Personal history of breast cancer
- Race, ethnicity (white women have increased risk compared with women of other races)
- History of radiation exposure
Unchangeable Risk Factors
Gender
Women are at greater risk of developing breast cancer. The risk of a man developing breast cancer is significantly lower.
Age
Your risk of developing breast cancer increases as you get older. About 2 out of 3 invasive breast cancers occur in women 55 years of age or older.
Genetics
About 5% to 10% of breast cancers are hereditary. This means the cancer is caused by a gene mutation, which was passed down from a parent.
The BRCA1 and BRCA2 genes are the most common causes of hereditary breast cancer. Breast cancers caused by these genes are more often found in younger women, and can affect both breasts. In the United States, BRCA mutations are common in Jewish women of Ashkenazi (Eastern European) origin; however, they can occur in anyone. Genetic testing can be done to find such mutations. If you are considering genetic testing, it is important to speak with a healthcare professional first to better understand the procedures and if it is the right option for you.
To learn more about genetic mutations which may cause breast cancer, visit: American Cancer Society.
Family History
The risk of breast cancer increases in women who have a relative on either their mother’s or father’s side of the family. However, less than 15% of women who have breast cancer have a family history of the disease. Therefore, the majority of women who get breast cancer have no family history at all.
Personal History
A women with breast cancer in one breast has an increased risk of getting a new cancer in another part of the same breast, or the other breast. This is not the same as the return of the first breast cancer.
Race and Ethnicity
Caucasian women are more likely to develop breast cancer but African American women are more likely to die from it. The risk of developing breast cancer in younger women is higher for African American women as well. The risk of developing and dying from breast cancer is lower in Asian, Hispanic, and Native American women.
Breast Density
Women with dense breast tissue have an increased risk of developing breast cancer. Age, menopause, pregnancy, genetics, and some drugs may affect the density of breast tissue.
Benign Breast Conditions
Some women with benign breast conditions have an increased risk of developing breast cancer.
To learn more on benign breast conditions which may cause cancer, visit: American Cancer Society.
Exposure to Diethylstilbestrol (DES)
Diethylstilbestrol (DES) is an estrogen-like drug which was given to some women in the 1940s through the 1970s. If you or your mother (while she was pregnant with you) took DES, it may have increased your chance of developing breast cancer.
Menstruation
If you had your menstrual cycle start before the age of 12, you may have an increased risk of developing breast cancer.
Menopause
If you started menopause after 55 years of age, you may have an increased risk of developing breast cancer.
Previous chest radiation
If you were treated with radiation therapy to the chest area as a child, you may have an increased chance of developing breast cancer.
Lifestyle-related factors are habits or behaviors people participate in. Most of the time they are factors you can control.
Risk Factors That Can Be Modified
- Reproductive factors
- Age at first live birth (full-term pregnancy after age 30 yr)
- Parity
- Lack of breastfeeding
- Obesity
- Alcohol consumption
- Tobacco smoking
- Use of hormone replacement therapy
- Decreased physical activity
- Shift work (night shifts)
- Histologic Risk Factors
- Proliferative breast disease
- Atypical ductal hyperplasia
- Atypical lobular hyperplasia
- Lobular carcinoma in situ
Environmental And Lifestyle Risk Factors
Lack of Physical Activity: A sedentary lifestyle with little physical activity can increase your risk for breast cancer.
Poor Diet: A diet high in saturated fat and lacking fruits and vegetables can increase your risk for breast cancer.
Being Overweight or Obese: Being overweight or obese can increase your risk for breast cancer. Your risk is increased if you have already gone through menopause.
Drinking Alcohol: Frequent consumption of alcohol can increase your risk for breast cancer. The more alcohol you consume, the greater the risk.
Radiation to the Chest: Having radiation therapy to the chest before the age of 30 can increase your risk for breast cancer.
Combined Hormone Replacement Therapy (HRT): Taking combined hormone replacement therapy, as prescribed for menopause, can increase your risk for breast cancer and increases the risk that the cancer will be detected at a more advanced stage.
Alcohol Consumption
The risk of developing breast cancer increases with the amount of alcohol you consume. Excessive alcohol consumption is also linked to the increase of several other cancers.Drinking in moderation includes one drink per day for women and two drinks a day for men, as defined by the United States Department of Agriculture.
Obesity
Being overweight after menopause may increase your risk of getting breast cancer.
Motherhood
Never having children, or having children over the age of 35 may increase your risk of developing breast cancer.
Hormone replacement therapy (HRT)
Hormone replacement therapy (HRT) can cause dense breasts, which make it more difficult for cancers to be detected in breast tissue. Some types of HRT can also increase your risk for developing breast cancer.
It is important to speak to your doctor about any concerns you may have in regards to breast cancer. Your doctor may recommend lifestyle changes and/or other approaches in order to help lower your risk of developing breast cancer.