Dense Breasts

ADULT AND GERIATRICS
A woman with dense breasts has a mammogram procedure done with an African American mammography tech. You can only see the back of the patient's head.

Credit: Robert A. Lisak

Why Yale Medicine?
  • We are leading experts in dense breast screening.
  • We simultaneously perform 3-D (tomosynthesis) and 2-D mammograms at no additional cost above the expense of 2-D mammograms.
  • Our four screening clinics are equipped with 3-D mammogram technology.

Annual mammograms are recommended for women age 40 and over to screen for breast cancer. Your radiologist may then notify you if you have “dense breast tissue” (as about half of women do). It’s nothing to worry about, but additional screening tests are recommended because mammograms are less accurate in detecting cancer in women who have dense breasts.

You can’t tell if your breasts are dense simply based on your body type, weight or the size and feel of your breasts. “Dense breast tissue is determined by the way the breast looks on the mammogram, not by how the breasts feel on physical examination,” says Regina Hooley, MD, a Yale Medicine radiologist, who is a breast imaging expert at the Breast Center at Smilow Cancer Hospital. Women with dense breasts should consider further tests, including ultrasound or magnetic resonance imaging (MRI). At Yale Medicine, women who don’t have dense breasts are told this when their mammograms are read, so they don’t have to wonder.

Be sure to contact your insurance company before scheduling a mammogram or additional screenings to check your coverage.

Breasts are made up of a combination of glandular and fatty tissues. They’re considered dense if most of the breast is made up of glandular tissue, and fatty if those tissues are predominant.

“The glandular tissue looks white, while the fatty tissue looks grey or black in a mammogram.  We are always looking for small cancers, which are white spots, so dense breast tissue makes the cancer harder to see,” says Dr. Hooley. Research shows that mammograms can be 80 to 98 percent effective in detecting breast cancer in women with non-dense breast tissue. However, the accuracy of mammography drops dramatically, possibly to as low as 50 percent, for women with dense breast tissue.