Movies and TV aren’t the only things going 3D; so is breast cancer
screening. That’s thanks to
3D digital breast tomosynthesis (DBT). Simply put, traditional mammography—whether film or digital—is
“a two-dimensional image of a round, three-dimensional structure,
namely your breast,” explains
Patricia E. Sacks, MD, director of the
Polak Breast Diagnostic Center at Torrance Memorial Medical Center.
“If you think of the breast as a solid ball, there may be a tiny
pearl [potential cancer] within it. A 2D mammogram allows you to see the
entire ball but not the pearl,” she says. With a 3D tomosynthesis
mammogram, a physician can take tiny, 1-millimeter images of the breast
in “slices” that allow a radiologist to see clearly what may
3D mammography technology is fairly new and not widely available—Torrance
Memorial is the only center in the South Bay to have the machine—but
it has been used in Europe for some time. Studies show tomosynthesis to
be reliable for diagnosing breast cancer.
“The accuracy of a 3D mammogram is better than 2D. Using a 3D mammogram
increases the detection of invasive cancer by 41% and increases detection of
all breast cancers by 29%,” Dr. Sacks explains.
Because the 3D test is more accurate, “false positives,” in
which a woman is called back because of a worrisome test result that proves
to be nothing, are lower. “That’s a big plus; you don’t
have to recall someone for additional views and more exposure to radiation
and make them crazy,” notes Sacks. “We’re able to decrease
that recall rate by 15%, at least.”
A 3D mammogram is useful for all women, including those with a strong family
history of breast cancer, previous breast biopsies and/or a BRCA mutation,
as well as those with dense breasts.
“When breasts are dense, our accuracy for [traditional] mammogram
may not be better than 50%,” says Sacks. “By adding 3D, we
really increase the chance of finding a breast cancer early.”