Tomosynthesis Plus Mammo Detect More Cancers in Dense Breasts

CHICAGO - Tomosynthesis may significantly increase cancer detection rate in mammography screening of women with dense breast tissue, according to a new study presented today at the annual meeting of the Radiological Society of North America (RSNA).

Researchers from Norway compared breast cancer detection using full-field digital mammography (FFDM) versus FFDM plus digital breast tomosynthesis (DBT) among women with dense breast tissue who underwent mammography screening.                              

"Tomosynthesis could be regarded as an improvement of mammography and would be much easier than MRI or ultrasound to implement in organized screening programs," lead author Per Skaane, MD, PhD, said in a release. "So the intention of our study was to see if tomosynthesis really would significantly increase the cancer detection rate in a population-based mammography screening program."

The prospective screening trial comprised 25,547 women, aged 50 to 69, who underwent both FFDM and DBT. The trial had four arms; this analysis included two: one offering FFDM alone versus FFDM plus DBT. Breast density was classified based on the American College of Radiology's Breast Imaging-Reporting and Data System (BI-RADS).

The results showed 257 malignancies detected on FFDM and a combination of FFDM and tomosynthesis in the study group.

A total of 211 (82%) of the 257 cancers were detected with FFDM plus tomosynthesis, a significant improvement over the 163, or 63%, detected with FFDM alone. FFDM plus tomosynthesis pinpointed 80% of the 132 cancer cases in women with dense breasts, compared to only 59% for FFDM alone.

The researchers concluded that cancer detection rate increased with the use of tomosynthesis in mammography screening among women with breast density BI-RADS 2 to 4, but not among women with a classification of 1.

"Our findings are extremely promising, showing an overall relative increase in the cancer detection rate of about 30 percent," Skaane said in the release. "Stratifying the results on invasive cancers only, the relative increase in cancer detection was about 40 percent."