Breasts are made up of a mixture of fibrous and glandular tissue and fatty tissue. Your breasts are considered dense if you have a lot of fibrous or glandular tissue but not much fat. Density may decrease with age, but there is little, if any, change in most women.
Having dense breast tissue may increase your risk of getting breast cancer. They also make it more difficult for doctors to spot cancer on mammograms, because dense tissue appears white on a mammogram as do benign and cancerous lumps.
Breast density is determined by the radiologist who reads your mammogram. Your doctor should be able to tell you whether you have dense breasts based on where you fall on the mammographic density scale:
Yes. A mammogram is the only medical imaging screening test proven to reduce breast cancer deaths. Many cancers are seen on mammograms even if you have dense breast tissue.
Studies have shown that ultrasound and magnetic resonance imaging (MRI) can help find breast cancers that can’t be seen on a mammogram. However, both MRI and ultrasound show more findings that are not cancer, which can result in added testing and unnecessary biopsies. Also, the cost of ultrasound and MRI may not be covered by insurance.
If you have dense breasts, please talk to your doctor. Together, you can decide which, if any, additional screening exams are right for you.