Breast Density

Dense Breast Tissue

Dense Breast Tissue

Breast density isn’t based on how your breasts feel and it’s not related to breast size or firmness. Breast density is seen only on mammograms.

Dense breasts are normal, but also increase the risk for breast cancer. If your breasts are dense (more than 50% fibroglandular tissue), you may need more testing after your mammogram to help assess your breast health.

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What is dense breast tissue?

Dense breast tissue refers to the appearance of breast tissue on a mammogram. It’s a normal and common finding. Breasts are made up of a mixture of fibrous, glandular and fatty tissue. Your breasts are considered dense if you have a lot of fibrous or glandular tissue and not too much fat. On a mammogram dense tissue looks white. Since masses or lumps also appear white on a mammogram, a suspicious lump may be masked by the dese breast tissue.

How do I know if I have dense breast tissue?

Breast density is determined by the radiologist who reads your mammogram. There are four categories of mammographic density. The radiologist decides which category best describes your breast tissue density.

Radiologists classify breast density using a 4 level system

A: Fatty; B: Scattered fibroglandular density; C: Heterogeneously dense; D: Extremely dense

Why is breast density important?

Dense breast tissue is important for two reasons:

  1. Depending on how dense your tissue is, it may moderately increase your risk of developing breast cancer.
  2. Most importantly, dene breast tissue makes it much more difficult to find cancer on mammograms. Dense tissue can actually hide a chance when it is early and has the best chance for cure.

If I have dense breasts what other tests should I consider?

Studies have shown that supplemental imaging exams such as breast ultrasound and breast MRI can help find some breast cancers that can’t been seen on mammograms.

Breast MRI is by far the most accurate breast imaging test in use today. It is exceedingly rare for Breast MRI to miss an invasive breast cancer. To put this into perspective:

  • Mammography detects 4-5 cancers per 1000 women screened.
  • Ultrasound detects an additional 2-4 cancers per 1000 women screened.
  • Breast MRI detects an additional 15-18 cancers per 1000 women screened.

If you have dense breasts, please talk to your clinician. Together, you can decide which, if any additional screening exams are right for you.

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RCI Imaging Center
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Cedar Rapids, IA 52402
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Cedar Rapids, IA 52402
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