Dense Breast Tissue

Dense breast tissue is very common and is not abnormal. However, dense breast tissue can make it harder to find cancer on a mammogram and also may be associated with an increased risk of breast cancer.

Breast density describes the composition of a woman's breasts, which are made up primarily of:

• Fat.
• Breast tissue.
• Connective tissue.

Breast tissue is a network of lobules (sacs that produce milk) and ducts (tiny tubes that carry milk from the lobules to the nipple openings during breastfeeding).

Fat gives breasts their size and shape, while connective tissue holds everything in place.

When a woman is said to have “high breast density,” it means there is a greater amount of breast tissue and connective tissue in comparison to fat. Low breast density means there is a greater amount of fat compared to breast tissue and connective tissue.

Younger women, those who are premenopausal and women who are taking hormones for menopausal symptoms are all more likely to have dense breast tissue.

Other factors related to breast density include:

• Pregnancy.
• How many children a woman has had.
• Body weight.
• Genetics.

In January 2014, the Dense Breast Law went into effect, making Hawaii one of a handful of states to require that imaging centers notify women if they have dense breast tissue.

In addition to regular mammograms, 3-D breast tomosynthesis and breast MRI are other screening options to consider for women who have dense breast tissue.