Risks for Breast Cancer: Health History and Genetics

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. Talk with your doctor if you think you may be at risk. Risk factors for breast cancer include the following:

A family history (first-degree relative, such as mother, daughter, or sister) of breast cancer.
Inherited changes in the BRCA1 and BRCA2 genes or in other genes that increase the risk of breast cancer.
Drinking alcoholic beverages.
Breast tissue that is dense on a mammogram.
Estrogen (made in the body)
- Menstruating at an early age.
- Older age at first birth or never having given birth.
Taking hormones such as estrogen combined with progestin for symptoms of menopause.
Taking oral contraceptives (“the pill”).
Obesity.
Not getting enough exercise.
A personal history of invasive breast cancer, ductal carcinoma in situ (DCIS), or lobular carcinoma in situ (LCIS).
A personal history of benign (noncancer) breast disease.
Being white.
Treatment with radiation therapy to the breast/chest.

Breast cancer is sometimes caused by inherited gene mutations (changes).

The genes in cells carry the hereditary information that is received from a person’s parents. Hereditary breast cancer makes up about 5% to 10% of all breast cancer. Some mutated genes related to breast cancer are more common in certain ethnic groups.

Women who have certain gene mutations, such as a BRCA1 or BRCA2 mutation, have an increased risk of breast cancer. Also, women who have had breast cancer in one breast have an increased risk of developing breast cancer in the other breast. These women also have an increased risk of ovarian cancer, and may have an increased risk of other cancers. Men who have a mutated gene related to breast cancer also have an increased risk of this disease.

Adapted from the National Cancer Institute’s Physician Data Query (PDQ(r)) Cancer Information Summaries (http://www.cancer.gov/cancertopics/pdq)

Date Last Modified: November 25, 2014

For more information:

Go to the Breast Cancer health topic.