For women with an average risk of breast cancer, mammograms beginning at age 40 are recommended by many medical professionals.
The American Society of Breast Surgeons has now taken this one step further.
On Friday, they released an updated position statement, stating that women with average risk should have a mammogram yearly with advanced three-dimensional (3D) mammogram technology being the preferred option.
The older form of mammograms takes two images per breast with the assistance of X-ray technology. Experts say women get more benefit from the use of 3D mammograms, which take many more images.
“Imagine the breast as a thick book. A regular mammogram tries to see through all the pages by squishing it as thin as possible. A 3D mammogram looks one page at a time,” Dr. Deanna J. Attai, MD, an assistant clinical professor in the department of surgery at David Geffen School of Medicine at the University of California, Los Angeles, told Healthline.
She explained that the benefit of a 3D mammogram, also known as tomosynthesis, has to do with how the images are processed.
“A standard 2D digital mammogram takes two views of the breast, compressing from top to bottom and from side to side. We then take those two 2D images and envision how it applies to the three-dimensional breast,” Attai said. “With 3D mammography, the same two views are taken. However, the images are processed in thin slices similar to a CT scan or MRI.”
“Screening mammograms have proven to decrease the number of deaths from breast cancer,” Dr. Onalisa Winblad, MD, a breast radiologist at the University of Kansas Cancer Center in Kansas City, told Healthline. “Screening mammograms provide the best chance of detecting breast cancers when they are small and treatable. If we detect breast cancers when they are small and early stage, not only are more lives saved from breast cancer death, but women are also able to undergo less extensive surgeries and system therapies,” Winblad said. “I recommend women have a screening mammogram every year beginning at age 40. This screening regimen saves the most lives.”
Dr. Stamatia Destounis, MD, a radiologist and committee member of the Public Information Committee of the Radiological Society of North America, said women who visit facilities with 3D mammograms available should opt for the newer technology.
“Women of age for breast cancer screening, meaning 40 and over, should ask for a digital breast tomosynthesis (DBT) mammogram every year if they have the opportunity to choose 3D. It’s a more accurate mammogram,” she told Healthline.
Destounis says 3D mammograms may make it easier to spot cancers that hide in dense breast tissue.
The results of a 3D mammogram get interpreted on a computer workstation. Although they may take slightly longer for a radiologist to examine, these tests are more accurate.
“There are many images obtained throughout each breast allowing for higher accuracy to identify a small cancer and also reducing the chance of getting called back for a false alarm meaning dense tissue on top of dense tissue,” she said. “About 10 percent of women may get called back for an extra view because sometimes densities are created in the breast because of the dense tissue on top of tissue. The 3D mammogram helps reduce these false alarms.”
Breast tissue is made of milk ducts, milk glands, supportive dense breast tissue, and fatty, non-dense breast tissue. Women with dense breasts have less fatty tissue and more dense tissue.
On a standard mammogram, dense tissue appears as a solid white part of the breast, making it difficult for radiologists to detect cancers.
The primary benefit of 3D mammograms, experts say, is for women who have dense breasts. A radiologist can determine if a woman has dense breasts using a mammogram. Dense breasts are more common in younger women and those taking hormone therapy.
“The 2D mammogram, because it takes a single image, can’t always see through dense breast tissue. Cancers also appear dense on a mammogram,” said Attai. “Because DBT looks slice by slice, it can pick up more cancers and abnormalities, especially in dense breast tissue. DBT isn’t necessarily better than 2D mammography for calcifications.”
Although annual breast screening is recommended for women aged 40 and over, some women may avoid the scan due to fear.
Diana Miglioretti, PhD, a professor in biostatistics at University of California, Davis, and a scientific member of the UC Davis Comprehensive Cancer Center, said it’s important women continue with regular scans and communicate their fears with their doctors.
“Mammography screening every one to two years saves lives,” Miglioretti told Healthline. “The exam is short, and any discomfort is usually minimal and brief. A good mammography facility will make sure women are comfortable during their visit. When scheduling a mammogram, women should let the staff know of any fears so they can help ensure a good visit,” she said.