New Ultrasound Approved for Dense Breast Screening

Patient Expert

Do you have dense breasts? An FDA advisory panel has recently approved a medical device that improves the effectiveness of your annual mammogram screening.

Did you know that breast density has been identified as a leading risk factor for breast cancer?

And that women identified as having dense breasts are 4 to 6 times more likely to be diagnosed with breast cancer than those with less-dense breasts?

"Dense breasts," a specific genetic condition that affects about 40% of all women being regularly screened for breast cancer, is based on the amount of fat tissue in your breasts: the less fat tissue, the higher your breast density.

But it's a characteristic, as well as a genetic condition. There's a huge range in breast density among women, with some exhibiting nearly all fat tissue in their breasts, while others have nearly none. In addition, being large-breasted doesn't automatically mean your breast density is low; and small breasts aren't always dense.

So how do you know if you have dense breasts?

While small-breasted and younger women are more likely than larger breasted/older women to have dense breasts, it's not something you can determine yourself.

Next time you have a mammogram, read the radiologist's complete report (if it's available). If it says your breast tissue is "heterogeneously dense," "very dense," or "extremely dense;" or if you see a "BI-RADS composition density" score of 3 or 4, then you have dense breasts.

If there's no indication of breast density in your mammogram report, contact the radiologist who read it, or your regular doctor; s/he should be able to give you details of the mammogram report. It's important to check this each time you have a mammogram, as breast density tends to change over the years.

Why does it matter how dense your breasts are?

Well, it makes a big difference when it's time for your annual mammogram.

Dense breasts can "hide" tumors from the X-rays used for mammogram screening. In an X-ray, fat tissue shows up clear, while breast tissue and tumors both show up opaque. Thus a woman with more breast tissue than fat (dense breasts) runs the risk of tumors being camouflaged within her breast tissue.

Even under the best conditions, mammograms miss up to 15% of cancerous tumors; in women with dense breasts, a standard mammogram is accurate in picking up tumors only 30% to 50% of the time.

Thus a recent action by a government FDA advisory panel could be good news for women with dense breasts.

This advisory panel has approved a simple screening technique (automated breast ultrasound screening) that, when used in conjunction with mammograms, showed 30% improvement over mammogram alone in identifying cancerous tumors. This technique is already in use in Canada and Europe, and could gain full FDA approval within the next year or so.

At this point, the somo-v Automated Breast Ultrasound System (ABUS) is approved only for women who are at normal risk for breast cancer, aside from their dense breasts. It isn't recommended for women with increased risk due to genetic issues (BRCA1 and BRCA2 carriers); for women who've been diagnosed with breast cancer in the past; or women who've had a breast aspiration or biopsy, even if negative.

Why the exclusions? Because the technique's down side is a proclivity for false positive results, which are higher anyway in women being checked more closely due to a previous history of breast issues.

However, the FDA board said this exclusion may change; and that in the meantime, women with dense breasts and previous breast issues should speak to their physician about whether the test might be appropriate for them.

Extra: read all about dense breasts.


Phend, C. (2012, April 13). FDA panel OKs ultrasound to screen dense breasts. Retrieved from