Dense breasts can complicate tests

Women are being encouraged to get their annual breast cancer screening and for good reason. Screening can save lives.

But what if your mammogram shows that you have dense breasts?

“Breast density is a radiologic term, and it’s specifically referring to how the breast tissue appears on a mammogram,” says Dr. Christine Klassen, a Mayo Clinic Breast Clinic physician.

The breast tissue is made up of fibrous tissue, glandular tissue and fatty tissue. Klassen says dense breasts may make screening more difficult.

“The dense breast tissue on a mammogram is when we see a lot of that glandular and supportive tissue, and not so much of the fatty tissues.”

Breast density is assigned one of four levels — A, B and C, and D, which is extremely dense.

“The higher-density group has about four times the risk of a cancer, compared to the lower-density group,” she says.

Annual mammograms remain an important screening tool. Klassen says additional testing may help.

“We do think that there’s some benefit to getting the 3D mammogram, or the mammogram with tomosynthesis, which helps radiologists scan through the field of the breast and get a better sense for what’s a true mass.”