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The Mayo Clinic – What is Breast Density

1 August 2016 | By Wellend

Dr Loni Neal from The Mayo Clinic’s Breast Clinic explains breast density in this video. ¬†Below is a summary her discussion.

Women age 40 and older are advised to have yearly screening mammograms aimed at early detection of breast cancer as this has been shown to reduce death from breast cancer. In understanding the pros and cons of doing this test, women need to be aware of the fact that nearly half of the women who have screening mammograms have dense breasts.

Breast density cannot be identified by feeling or examining breasts, it can only be identified by mammographic examination.

Breast density refers to the relative proportion of fatty tissue versus fibrous or glandular tissue.  The breast is considered dense if the proportion of fibrous or glandular tissue (white on a mammogram) is greater than the proportion of fatty tissue (dark on a mammogram).

Mammographic breast density is most commonly classified by radiologists into one of 4 categories:

A) The breasts are almost entirely fatty
B) There are scattered areas of fibroglandular density
C) The breasts are heterogeniously dense, which may obscure small masses
D) The breasts are extremely dense, which lowers the sensitivity of mammography.