Factors relating to the breast itself

A three-star rating system has been used to give you an indication of the level of breast cancer risk associated with the factors below.

The greater the number of stars, the higher the risk.

A previous breast condition Rating starEmpty rating starEmpty rating star

Being previously diagnosed with a non-invasive breast condition such as ductal carcinoma in situ (DCIS) or lobular carcinoma in situ (LCIS), is associated with an increased risk of developing invasive breast cancer.

Breast density Rating starEmpty rating starEmpty rating star

Women with ‘dense’ breasts are more likely to be diagnosed with breast cancer than women with less ‘dense’ breasts.

Your breast density is something that can be measured on a mammogram. A mammogram of a woman with dense breasts will appear much like white cotton wool. A mammogram of a woman with less dense breasts will appear more grey and transparent. Breast density cannot be measured by physical breast examination.

Although breast density decreases with age and after menopause, there is a large difference in breast density across women of the same age.

Research to identify the reasons why women of the same age differ so much in breast density will lead to a better understanding of the causes of breast cancer and how to prevent it.*

* Queensland Institute of Medical Research (QIMR) study materials (2005) for Breast Density: A Twins and Sisters Study - Principal investigator Professor John Hopper, University of Melbourne; Co-investigator, Dr. Susan Treloar, QIMR.