Dense breasts have a higher proportion of fibrous and glandular tissue compared to fatty tissue. This density is common, particularly among younger women and those with lower body fat, and affects about 40-50% of women aged 40 and older. Breast density is typically measured during mammograms and classified into four categories: almost entirely fatty, scattered areas of density, heterogeneously dense, and extremely dense.
Dense breast tissue complicates cancer detection because it appears white on mammograms, the same color as many tumors, making it difficult to distinguish between normal dense tissue and potential cancerous growths. Consequently, small tumors may be obscured, potentially leading to delayed diagnoses. Women with dense breasts not only face diagnostic challenges but may also have an increased risk of developing breast cancer compared to those with less dense tissue. Additional imaging tests, such as ultrasound or MRI, are sometimes recommended to improve detection accuracy in dense breast tissue