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The Difference Between Dense and Nondense Breast Tissue

The Difference Between Dense and Nondense Breast Tissue

Do you have dense breast tissue? Would you know what it meant if you did?

Dense breast tissue describes the appearance of breast tissue on a mammogram; it’s normal and a common finding. Knowing whether you have dense breast tissue or not is a key factor in early detection of breast cancer. The density of your breasts helps determine whether a mammogram will be enough to detect breast cancer or if supplemental screening may be useful. 


What is Dense Breast Tissue?

Breasts contain glandular, connective and fat tissue. Dense breast tissue contains milk glands, milk ducts and supportive tissue. Non dense tissue contains fatty tissue. On a mammogram, nondense breast tissue appears dark and transparent, while dense breast tissue appears more solid and white, which makes it difficult to see through. 


How Do You Determine if You Have Dense Breast Tissue?

Dense breast tissue cannot be felt in a clinical breast exam or in a breast self-exam, it can only be  seen on a mammogram. Once you have your mammogram completed, the radiologist who  interprets the mammogram will determine the ratio of nondense tissue and dense tissue, and will assign a level of breast density. The radiologist typically will use a results reporting system called Breast Imaging Reporting and Data System (BI-RADS). The levels of density are divided into four categories:

A: Almost entirely fatty. This indicates the breasts are almost entirely made of fat. About 1 in 10 women have this result.

B: Scattered area of fibroglandular density. This means there are some scattered areas of density, but the majority of the tissue is nondense. This happens to about 4 in 10 women. 

C: Heterogeneously dense. This indicates that there are areas of nondense tissue, but most of the breast tissue is dense. About 4 in 10 women have this result. 

D: Extremely dense. This indicates that nearly all of the tissue is dense. Only about 1 in 10 women have this result. 


What Causes Dense Breast Tissue?

Almost half of women aged 40 and older who undergo mammograms are found to have dense breasts. This type of tissue is often inherited, but there are some factors that can influence dense breasts. If you have a lower body mass index, you are more likely to have dense breast tissue than women who are obese. You may also have a higher chance of dense breast tissue if you take hormone therapy for menopause.


Are There Recommended Tests or Screenings for Breast Cancer?

It is recommended by most medical organizations that women with an average risk of breast cancer have a mammogram once a year, beginning at age 40.  A 3-D mammogram, also called a  mammogram with tomosynthesis, uses X-rays to collect several images of the best from multiple angles. The images are then synthesized by a computer to create a 3-D image of the breast. This is the most advanced type of mammogram, allowing the radiologist to detect more cancer and decrease the chance that women need further testing.

You and your physician may consider supplemental testing based on your other risk factors and personal preferences. Other tests include: 

  • Breast MRI. MRI uses magnets to create images of the breast and  doesn’t use radiation. This screening is recommended for women with a very high risk of breast cancer.
  • Breast Ultrasound. This imaging test uses sound waves to analyze the breast tissue. Ultrasound can be used to look at all the tissue in both breasts, or can be targeted to investigate areas of concern discovered on a mammogram.


The Breast Center at ImageCare 

Community Care Physician is proud to have The Breast Center at ImageCare, one of the Capital Region’s few full-service breast centers providing the latest in breast cancer screening and diagnosis. Our accredited facility provides state-of-the-art technology paired with excellent patient care to serve the women’s breast health needs. Our subspecialized radiologists and team of specialists are Board-certified radiologists who focus on  breast imaging, leaders in interpreting, mammograms, breast ultrasound, and breast MRI, and performing image-guided procedures. 

The Breast Center at ImageCare not only specializes  in breast screening and diagnosis, it also provides patients with access to our unique Oncology Nurse Navigator to help patients navigate the healthcare landscape for cancer screening, diagnosis, treatment and support services. The Breast Center has two full service locations in Latham and Clifton Park, and ImageCare Medical Imaging also provides mammography services in Saratoga Springs. Click here to view The Breast Center at ImageCare’s website and learn more about their services and specialized and dedicated staff. 


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Original posting date: 10/24/2018

Updated: 9/16/2019

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