You May Not Need a 3D Mammogram

3D mammography most helpful for women with dense breasts and a high risk of cancer.

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Key Takeaways

  • A new study has found that digital breast tomosynthesis (DBT)—also known as three-dimensional (3D) mammography—is not necessarily more beneficial than a standard 2D mammogram.
  • The research found that DBT did offer benefits for people with dense breasts and a high risk of breast cancer.
  • While most people may not need a 3D mammogram, the study did not necessarily show that there were any downsides to getting one.

According to a new study, you're not likely to benefit from having a 3D mammogram unless you have dense breast tissue and a higher risk of developing breast cancer.

Digital breast tomosynthesis (DBT) is the technical term for 3D mammograms. Karla Kerlikowske, MD, a lead author of the study and a professor in the Department of Medicine and Epidemiology and Biostatistics at the University of California, San Francisco, told Verywell that DBT uses low-dose X-rays to get views of the breast from different angles and assembles 3D images.

“The 3D is almost like a CT [computed tomography] scan of the breast,” said Kerlikowske. “You are looking at slices through the breast.”

While it's high-tech, the researchers found that most people in the study did not benefit from 3D mammograms over the standard 2D technique.

3D Mammograms May Not Help—But Do They Hurt?

Kerlikowske said that when 3D mammograms first became available in 2011, they were only required if a person's dense breast tissue made the 2D screening less helpful or if something was seen on the 2D screening required follow-up.

The double screening meant that patients got a double dose of radiation. However, both doses were small.

According to Kerlikowske, the study showed there were no risks of using 3D mammography compared to 2D mammography, even though the benefits were small.

Who Should Get 3D Mammograms?

The study suggests people with a high risk of breast cancer and extremely dense breasts benefit from 3D mammograms the most.

Some people are more likely to have dense breast tissue, including younger people, people taking hormone replacement therapy, people who are pregnant or breastfeeding, and people with less body fat.

To come to this conclusion, researchers used records from 504,427 women who had screening mammograms between 2011 and 2018 at 44 U.S. Breast Cancer Surveillance Consortium facilities.

The women in the study were between the ages of 40 and 79 years old. Some of them had only 2D mammograms, some had only 3D mammograms, and some had both.

The researchers compared the rates of interval cancer and advanced cancer for each kind of mammogram.

What Is Interval Cancer?

In an editorial published with the study, the authors explained that interval breast cancer is one that is found during screening but that was not seen (or was not visible) during a previous screening. The authors wrote that “in essence, interval cancers are a result of screening failures."

The researchers found that:

  • Interval cancer rates were not significantly different between the women who had a 3D mammogram and the women who had a 2D mammogram, no matter how dense their breasts were.
  • Advanced cancer rates were not significantly different in patients who did not have dense breasts or in patients who had dense breasts but a low-to-average risk of breast cancer.

Where was there a difference? The 3.6% of women in the study who had extremely dense breasts and a high risk of breast cancer had a lower risk of advanced-stage cancer if they had received 3D mammograms instead of 2D mammograms.

Potential Benefits of 3D Mammograms

Stamatia Destounis, MD, FACR, a spokesperson for the American College of Radiology (ACR) and chair of the ACR's Breast Imaging Commission, told Verywell that the study showed that patients who had 3D mammograms instead of traditional digital mammography had a lower false-positive rate (when the screening shows something but no cancer is found).

Fewer false-positive results could mean less anxiety for patients about a possible cancer diagnosis and fewer breast biopsies or other diagnostic tests, but the researchers did not consider the finding to be statistically significant.

Destounis, who was not involved with the research, said that other studies have shown that 3D mammograms can reduce call-backs for more screening and short-term follow-ups, which are “overall, all good points and positives for DBT.”

How Can You Get a 3D Mammogram?

Even if most patients don't need a 3D mammogram, having the ability to offer one to the patients who would is important.

Destounis said that today, most mammography facilities have at least one DBT unit for 3D mammograms and that there are nearly 11,000 such units in the United States (out of just over 24,000 total mammography units).

Both Destounis and Kerlikowske said that many centers are transitioning to 3D mammography as their older technology wears out and needs to be replaced.

A DBT imaging machine can be a good investment for providers who want to keep pace with their patients' needs and preferences. Kerlikowske said that if it's set to do so at the time of an exam, the DBT machine can be also used to create 2D digital mammograms.

“There are some women who only want the 2D for different reasons," said Kerlikowske. "One is that some insurance companies charge a copay for 3D and it's up to $50.”

According to Kerlikowske, health insurance companies are required by the Affordable Care Act (ACA) to cover screening mammograms with no copay, but some only offer that for 2D mammograms.

What This Means For You

If you have dense breast tissue and a higher risk of developing breast cancer, you may benefit from having a 3D mammogram.

If you have dense breasts and a low-to-average risk of breast cancer, research has shown that you probably won't get more benefit from a 3D mammogram than you would from a standard 2D mammogram.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Kerlikowske K, Su YR, Sprague BL, et al. Association of screening with digital breast tomosynthesis vs digital mammography with risk of interval invasive and advanced breast cancerJAMA. 2022;327(22):2220-2230. doi:10.1001/jama.2022.7672

  2. U.S. Food and Drug Administration. DBT accreditation: It's here.

  3. Centers for Disease Control and Prevention. What does it mean to have dense breasts?

  4. 3D mammograms reduce risk of advanced-stage disease in women with extremely dense breasts and high risk of breast cancer.

  5. Friedewald SM, Grimm LJ. Digital breast tomosynthesis and detection of interval invasive and advanced breast cancers. JAMA. 2022;327(22):2198–2200. doi:10.1001/jama.2021.25018

By Valerie DeBenedette
Valerie DeBenedette has over 30 years' experience writing about health and medicine. She is the former managing editor of Drug Topics magazine.