What Is Tomosynthesis (3D Mammography) and Why It Matters for Breast Cancer Detection

At Independent Physicians Medical Center (IPMC) in Northeast Philadelphia, we offer cutting-edge breast imaging services including tomosynthesis as part of comprehensive breast health care, delivered in a welcoming outpatient setting.

What Is Tomosynthesis?

Tomosynthesis — also referred to as digital breast tomosynthesis (DBT) — is a specialized form of mammography that creates three-dimensional images of the breast. Instead of taking only one flat picture like a traditional mammogram, the imaging arm sweeps in a slight arc around the breast and captures multiple low-dose X-ray images from different angles. These are then reconstructed by a computer into a detailed 3D view.

This layered view allows radiologists to “scroll through” the breast tissue like pages in a book, reducing the effect of overlapping tissue that can hide small cancers or create false alarms on standard 2D mammograms.

How Tomosynthesis Improves Cancer Detection

More Accurate Screening, Especially in Dense Breasts

Dense breast tissue — which is common in many women — can make it harder to see tumors on traditional mammograms because both dense tissue and cancer appear white on 2D images. Tomosynthesis helps separate overlapping structures, making suspicious areas easier to detect.

Fewer False Positives and Callbacks

Because of the 3D detail, tomosynthesis often reduces unnecessary callbacks for additional testing due to ambiguous findings on 2D images. Physicians can see more clearly whether a suspicious area is real or just overlapping tissue.

Early Detection of Small Tumors

Studies have shown that 3D mammography may increase the detection of breast cancers — especially small or subtle lesions — compared with standard mammography alone. This means cancers can be found earlier, when treatment is most effective.

When Is Tomosynthesis Recommended?

Tomosynthesis may be used for:

• Routine breast cancer screening, especially for women starting around age 40
• Diagnostic imaging when symptoms like a lump, nipple discharge, or breast pain are present
• Follow-up exams after an abnormal finding on a traditional mammogram
• Women with dense breast tissue, where standard mammography may be less effective

Your doctor will determine whether tomosynthesis, a standard mammogram, or a combination provides the best assessment for your individual situation.

What to Expect During a Tomosynthesis Exam

The tomosynthesis experience is similar to a traditional mammogram:

1. You’ll stand in front of the mammography machine.
2. A technologist positions one breast at a time on a platform.
3. The breast is gently compressed between two plates.
4. The machine sweeps around your breast, taking many quick images.
5. A computer reconstructs these into a detailed 3D view.

The process is quick and uses low-dose X-rays, meaning radiation exposure remains minimal while providing maximum detail.