What is your breast cancer risk?
Am I at risk?
1 in 7 women will get breast cancer
Most women with breast cancer do not have a family history of the disease.
Age is the biggest risk factor for developing breast cancer.
Major risk factors
Other than being female, age is the most significant factor for developing breast cancer. The risk of breast cancer increases with age up to 75 years. Over 75% of all breast cancers in Australia are diagnosed in women when they are aged 50 years or over. The average age of the first diagnosis of breast cancer in women is 61.
Breast cancer is common and most breast cancers are not caused by genetic factors. Therefore most women's family history of breast cancer is due to chance alone. For a small number of women with a family history, this may be due to a gene change in a blood relative that increased the risk of cancer.
(i) Family history of breast cancer or ovarian cancer
Your family history becomes important when:
- More than one relative on the same side of your family (mother's or father's side) has been diagnosed with breast cancer
- Relatives are diagnosed with breast cancer at a young age (under 50 years of age) and closer to you (for example, you sister rather than your cousin)
- If a family member has breast cancer in both breasts
- Male breast cancer
- Both breast and ovarian cancer exists in your family
(ii) Gene mutations
Various gene mutations increase the risk of breast cancer. These include BRCA 1 and BRCA 2.
(iii) Family history of other cancers
A family history of prostate cancer and pancreatic cancer is also associated with an increased risk of breast cancer.
Risks are higher as more relatives are affected by the various cancers, and if a woman also has relatives affected by breast cancer.
Women with dense breasts on mammography are more likely to develop breast cancer than women with average breast density.
Previous diagnosis of breast cancer
Having had breast cancer yourself is associated with an increased risk of a second primary breast cancer. A second primary breast cancer refers to a new primary breast cancer, which is different from a recurrence of the initial cancer.
Previous benign breast disease
Benign breast disease is a broad group of conditions with non-cancerous changes in breast tissue. A history of proliferative benign breast disease is associated with an increased risk of breast cancer. These conditions include LCIS, ADH, and ALH. BreastScreen Victoria offers yearly screening for women with these conditions.
Modifiable risks that may increase your risk of breast cancer are alcohol consumption, smoking, and obesity.
Calculating your risk
You can find out more about your personal risk of developing breast cancer by using one of these online risk calculators.
- iPrevent – developed by the Peter MacCallum Cancer Centre
- Your risk and breast cancer - developed by Cancer Australia also includes information to help understand how risk is calculated
Reducing your risk
You cannot change your age or the other major risk factors above, but there are simple choices you can make in your everyday life to reduce your risk. These include drinking less alcohol, quitting smoking, managing your weight, staying physically active, and eating healthy foods.