Dense Breasts

Breasts are not just two lumps on the chest wall: they are composed of metabolically active tissue that adapt in response to time, outside stresses and health changes. Since breasts are not static, it is important to have mammograms at regular intervals to look for worrisome changes.

In a great simplification, breasts are composed of fibrous and fatty tissue. Dense breast have a higher proportion of fibrous tissue. Breast density is influenced by age (decreases after menopause), number of completed pregnancies, breastfeeding and certain medications. Fatty tissue appears black on mammograms and fibrous tissue shows as white. The big question: what is hidden in the tangle of white?

Forty percent of women older than age 40 have dense breasts. These women may benefit from additional breast imaging. Digital mammography (tomosynthesis) is more effective in detecting suspicious masses but may still miss cancer in very dense breasts. Ultrasound is often used as an adjunct and select patients may need MRI.

Physicians may recommend a program of breast studies for high risk patients. High risk for breast cancer include a first degree relative (mother, father, brother, sister or child) with breast cancer or certain gene mutations such as BRCA1 and BRCA2, hormone use and alcohol intake.

One out of eight American women will develop breast cancer in her lifetime. Early detection may improve outcomes.

To learn about breast cancer risk.

A discussion about breast density.