Do women with dense breasts need extra cancer screenings?

Recent news headlines suggest women with dense breast tissue need specialty care and exams to detect breast cancer.

But Therese Bevers, M.D., medical director of MD Anderson's Lyda Hill Cancer Prevention Center, says the news is ahead of the science.

"We understand that dense breast tissue is associated with an increased risk for breast cancer, but we don't fully understand that risk," Bevers says. "We need more research on how to manage women with dense breast tissue before we can say whether extra screening exams make a difference."  

Below, Bevers answers some common questions about dense breasts and screenings. 

What does it mean to have dense breasts?
Breast density describes the proportion of the different tissues that make up a woman's breast. Women with dense breasts have more glandular tissue (breast and connective tissue) than fat.

Also, breast density can only be determined by a mammogram. It's not a measure of feel, such as size or firmness.

Why the concern with dense breast tissue?
It can be harder for mammograms to detect abnormalities in women with dense breast tissue because glandular tissue is harder for imaging technologies to see through than fat.

But it's not impossible.

How do you talk to patients with dense breast tissue?
I approach my patients with dense breast tissue the same way I talk to those without.

Screening exams are based on risk, which is independent of breast density. If my patient has dense breast and is at average risk for breast cancer, I don't recommend supplemental screening. There's just no evidence to say whether extra screening makes a difference.

The evidence for extra screening is for women with dense breast tissue and at increased risk for breast cancer. So recommendations are based on risk, not breast density.

If patients are concerned, they can discuss supplemental screening with their health care providers.

If women are concerned, what extra screenings are available?
3D mammography or tomosynthesis is something that I encourage all women to consider. It's not limited to patients at increased risk or with dense breast tissue. Data shows 3D mammography improves detection of breast cancer with fewer false positives.

It's a good imaging tool because it's looking through millimeter slices of breast tissue, not the entire breast tissue. When you look at the tissue in slices, it's easier to detect abnormalities.

Who can get 3D mammography?
Patients can request 3D screening mammography -- it doesn't require a doctor's order. But you should check to make sure it's covered by insurance first. Most health care providers are submitting it to insurance plans, but we don't know if 100% of the cost is covered.

I tell all my patients to consider 3D mammography with the caveat that I don't know if insurance will cover it.