Breast Cancer in Young Women 1
Managing Risk
Breast cancer is common, affecting 1 in 9 Australian women by the age of 85. Approximately 95% of breast cancers are not related to a strong family history of breast cancer. In the other 5%, breast cancer develops because of an inherited gene fault (gene mutation). These gene faults can be passed through men and women in families, from one generation to the next. Any female family member who inherits this gene fault is at an increased risk of developing breast cancer.
This information is for women who have been assessed by a family cancer clinic as being at high risk of developing breast cancer and cancer of the ovaries and fallopian tubes, including:
- women who have had genetic testing and been found to carry a BRCA1 or BRCA2 gene mutation
- women who have not yet been found to carry a gene fault but whose family history puts them at potentially high risk of developing these cancers.
Am I at high risk?
Less than 1% of the Australian population is at high risk of developing breast cancer and cancer of the ovaries and fallopian tubes.Women who may be at high risk of these cancers have:
- had genetic testing and been found to carry a BRCA1 or BRCA2 gene fault that can cause these cancers, or
- a very strong family history of breast and ovarian cancer that often includes:
- several relatives with breast or ovarian cancer
- breast cancer before the age of 40
- breast cancer in men
- women who have had cancer in both their breasts
- women who have had both breast and ovarian cancer
- Ashkenazi Jewish ancestry
In addition to BRCA1 and BRCA2, there are other genes in which rare faults can also increase the risk of cancer.
How high is my risk?
The lifetime risk of breast cancer and cancer of the ovaries and fallopian tubes varies depending on the type of gene fault in your family.
For women with a BRCA1 gene fault
- the lifetime risk of breast cancer is between 40% and 80%
- the lifetime risk of ovarian and fallopian tube cancer is between 40% and 60%
For women with a BRCA2 gene fault
- the lifetime risk of breast cancer is between 40% and 80%
- the lifetime risk of ovarian and fallopian tube cancer is between 10% and 20%
People who carry these gene faults may also be at increased risk of other cancers.
About Breast Cancer
Breast cancer is very common, so a family history of breast cancer is also quite common. Most women who develop breast cancer do not have an inherited gene fault. In many cases, breast cancer can be found early using screening mammograms (or other imaging tests such as breast ultrasound or magnetic resonance imaging [MRI]). These tests may find a cancer before a woman can feel a lump in her breast. Even when breast cancer is found when a lump can be felt, there is a very good outlook. Modern treatments for breast cancer include surgery to remove the affected part of the breast (wide local excision or lumpectomy followed by radiotherapy) or the whole breast (mastectomy). This is often followed by chemotherapy and/or medications to block the effects of the hormone oestrogen.
Women who carry a BRCA1 or BRCA2 gene fault tend to develop breast cancer at an earlier age than other women, and are more likely to develop cancer in both breasts over time. The breast cancer that develops in these women is similar to breast cancer that develops in other women. When breast cancer is found early, women who carry these gene faults seem to have a similar survival rate to other women with breast cancer. Further research is underway to clarify this.
