> Family History of Breast, Ovarian or Prostate Cancer
A family history of certain types of cancer can increase your risk of breast cancer. This may be due to genetic factors (known and unknown), shared lifestyle factors and other family traits.
Most women with breast cancer do not have a family history of the disease. Only about 13 percent of women diagnosed have an immediate female relative (mother, sister or daughter) with breast cancer [48].
A woman who has one immediate female relative with breast cancer has almost twice the risk of a woman without a family history [48-50]. If she has more than one immediate female relative with a history of breast cancer, her risk is about three to four times higher [48-50]. In general, the younger the relative was when she was diagnosed, the greater a woman's chance of getting breast cancer [50]. Also, a woman whose mother was diagnosed with breast cancer before age 50 has about twice the risk of a woman without a family history [50]. For a woman whose mother was diagnosed after age 50, the increase in risk isn't as great.
Learn about the risk related to having a male relative with breast cancer below.
Male family members with a history of cancer and risk of breast cancer
When talking about family history, it's also important to consider the men in your family. A history of breast cancer in a close male relative (father, brother or uncle) can increase breast cancer risk [50].
A history of prostate cancer in one or more immediate relatives (father or brother) may also increase a woman’s risk of breast cancer, especially if the prostate cancer was found at a young age [51-53]. At this time, we don’t know exactly why a family history of prostate cancer might increase breast cancer risk though certain inherited gene mutations can increase risk of these cancers (see below).
Inherited gene mutations and risk of breast cancer
The breast cancer risk linked to family history may be due to shared lifestyle factors or due to genetic mutations that increase risk. Families with a strong family history of breast cancer often carry inherited genetic mutations. Such families may have more than one immediate relative (mother, sister or daughter) with breast cancer, a single female relative diagnosed at an early age or a male relative with breast cancer. Family history of ovarian cancer may also be related to an inherited genetic mutation.
Inherited genetic mutations account for only five to 10 percent of all breast cancers diagnosed in the United States [4-6].
Learn more about inherited genetic mutations and breast cancer risk.
Breast cancer screening for women with a strong family history of breast or ovarian cancer
There are special breast cancer screening guidelines for women with a strong family history of breast or ovarian cancer (for example, two or more first-degree relatives with breast cancer or two or more with ovarian cancer). If you have a strong family history, the National Comprehensive Cancer Network and the American Cancer Society recommend you get [43-44]:
- A clinical breast exam every six to 12 months starting at age 25
- A mammogram every year starting at the age five to 10 years prior to the youngest breast cancer case in the family
- An MRI every year in combination with a mammogram every year starting at the age five to 10 years prior to the youngest breast cancer case in the family
This medical care helps ensure that if cancer does develop, it is caught early when it is most treatable.
Learn more about breast cancer screening recommendations for women at higher risk.
People with limited information on family medical history
Some people may not know their family medical history. Risk assessment tools such as the Breast Cancer Risk Assessment Tool (Gail model) can estimate your breast cancer risk without this information. However, it will be less accurate without family history details.
Talking with your health care provider about other risk factors for breast cancer can help you learn more about your risk if you do not have family medical information.
Updated 11/17/11
