You may be surprised to know that 90–95% of all breast cancers have nothing to do with family history. While no one actually inherits breast cancer, a small number of women do inherit a genetic predisposition to the disease.
Approximately 5–10% of breast cancers occur in women whose families have a genetic fault. This is usually passed down through the family and exposes them to a greater risk of developing breast cancer.
BRCA1 and BRCA2 are gene mutations that are connected to hereditary breast cancer. Women who carry these mutations are also at increased risk of developing ovarian cancer.
There are also other rarer gene mutations that increase a woman’s risk of breast cancer, such as p53. Scientists believe there are still others that have not yet been identified.
Is breast cancer in your family?
If two or more of your relatives (mother, sister, daughter, grandmother, aunt or niece) on the same side of the family have been diagnosed with breast cancer, there is a chance your family may carry a breast cancer gene mutation.
While carrying a breast cancer gene mutation increases your risk of developing breast cancer, it does not mean that you will definitely get breast cancer.
As breast cancer can also affect men, it’s important to remember that the BRCA1 and BRCA2 mutations can also be passed through the father's side of the family.
If you are at all worried about the risk of breast cancer in your family, you may like to talk to your family doctor (GP) or local Family Cancer Clinic. If you are under 50, have no signs or symptoms of breast cancer, but have a high risk (family history or genetic mutation), you might be eligible for an MRI scan rebate.
Family Cancer Clinics
If your family has a strong history of cancer, including breast cancer, a Family Cancer Clinic may be able to help. If it is appropriate for you, they can arrange for you and your family to have genetic testing. This will determine whether you or another family member carries a BRCA1 or BRCA2 gene mutation. You will have access to counselling before and after testing.
Family Cancer Clinics can also help you draw up a health plan to regularly monitor your breasts for any changes if you are at increased risk of developing breast cancer.
There is no charge for a consultation or for genetic testing at a Family Cancer Clinic. They operate through public hospitals and are supported by the public health system. Your GP can refer you to a clinic in your area, or you can telephone a clinic yourself to make an appointment. You do not need a referral.
For more information about Family Cancer Clinics, visit the Cancer Council Australia website or phone the Cancer Cancer Helpline on 13 11 20.
Would you like more information on this topic? Here’s what to do:
- Read the Ask The Expert article in issue 62 of The Beacon magazine, where Assoc Prof Judy Kirk discusses breast cancer in families.
- Read the Family history fact sheet.
- Take a look at BCNA's Family history position statement. It outlines the key issues that many women face in this situation.
- Consider using Cancer Australia's risk calculator to understand your risk of developing breast cancer.
- Discover the personal stories that are posted in this section.
- Read the latest research about family history and hereditary breast cancer.
- Visit the NSW Centre for Genetics Education website. It has information about genetic testing, including an information and decision aid.
- Visit the Westmead Breast Cancer Institute website. They have a Family history of breast cancer brochure which you can order free of charge.
- Take a look at the US-based FORCE website. It has more information about family history and hereditary breast cancer and you can sign up to their regular ebulletins.
- Watch the Cancer Council Victoria webinar on the topic of Breast Cancer in your family.
- Visit the Kathleen Cuningham Foundation Consortium for Research into Familial Aspects of Breast Cancer (kConFab) website. KConFab is a national group of researchers who hope to solve questions about hereditary breast cancer. These researchers have access to breast cancer families that have agreed to participate in studies, through providing blood and tissue samples. You can find out more about the eligibility criteria and current research on their website.
One cancer family
Hear Judith Maher’s story of her daughter Maryanne who was diagnosed with breast cancer aged 30. Judith was subsequently diagnosed with breast cancer, as was her sister.