Thanks for coming to learn more about the #breastkeptsecret! The aim of this website is to ensure women are aware of the importance of breast density in the screening and diagnosis of breast cancer.


What is breast density?

Breasts are made up of different types of tissue – fibrous, glandular and fatty. Fibrous and glandular tissue appears white on a mammogram and fatty tissue shows up as dark. If most of the tissue on a mammogram is fibrous and/or glandular, the breasts are said to be dense.


Why is breast density important?

Women with high breast density are both at a higher risk of developing breast cancer, and also at an increased risk of breast cancer not being detected by a mammogram.

How do I know if I have dense breasts?

Breast density is not something you can feel by touch. It can only be determined by a radiologist (doctor) on a breast screen i.e. a mammogram. Once you’ve had a mammogram, you can check with your referring doctor to see how dense your breasts are.


What should I do if I have dense breasts?

All women should maintain a regular breast screening program. If you have high breast density speak with your doctor about appropriate next steps. This may include additional screening.



Is it common to have dense breasts?

Dense breast tissue is common among women and usually decreases over time with age. However, your breast tissue will usually fall onto one of four categories. In Australia, these categories are defined as:

Category 1: Predominantly Fatty Breast (will have less than 25% glandular tissue present and therefore will have very little white on a mammogram)

Category 2: Scattered Fibroglandular Breast (will have between 25 – 50% glandular tissue present so will have a few scattered white spots on a mammogram)

Category 3: Heterogeneously Dense Breast (will have between 50 – 75% glandular tissue present and as such there will be more white visible on a mammogram)

Category 4: Extremely Dense Breast (will have greater than 75% glandular tissue present and will appear to be very white on a mammogram)

How can dense breasts affect a mammogram?

Dense breast tissue (or breasts with less fatty tissue) appears white on a mammogram, as does cancer. This can make it hard for a radiologist to detect early stage breast cancer on a mammogram.

Please browse the website further to learn about dense breast tissue, and use the available resources.