Your breast cancer risk

Age

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.

Family history 

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, your 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.

Breast density

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.

It's important to note that we only report on signs of breast cancer and not other changes or lumps that are determined benign or non-cancerous. This includes cysts or changes that have remained the same since your last breast screen.

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

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.