Study: New 3-D Technique More Accurate Than Mammography

A new high-tech system that produces three-dimensional images of the breast may not only help doctors better identify early signs of breast cancer, but may also dramatically reduce the number of women called back for a second mammogram because their first was unclear.

The technique, called full-field digital tomosynthesis (TOMO), is viewed by some researchers as potentially the next generation of breast cancer screening.

Dr Elizabeth Rafferty of Massachusetts General Hospital reported at the American Roentgen Ray Society annual meeting on two studies which have produced highly promising results.

In the first study comparing TOMO against standard plain film mammography, 22 of the 40 women participating had a malignant growth in the breast. A standard mammogram correctly identified 16 of the 22 but TOMO identified two more.

The second study focused on 45 women who had been called back for a second mammogram because their first showed a possible abnormality. Thirty were subsequently found to have a harmless irregularity in their breast tissue.

Radiologists examined TOMO scans of the 30 women, and concluded that if the results had been available, only five would have been called back.

"If we could have used TOMO on these patients initially, it would have saved 25 women the anxiety they felt and the inconvenience they experienced of being called back for additional tests," Rafferty said.

TOMO works by taking multiple projections of the breast at different angles., which are then reconstructed into a three-dimensional data set.

"We can then look at each slice individually and assess each area of the breast without confusing overlap from surrounding structures,” Rafferty said. “The ability to look at individual slices of the breast is a real asset."

TOMO also is more comfortable for the patient. The patient’s breasts only need to be compressed once (compared to twice for the standard two-view mammogram); the patient sits during the procedure, and the overall radiation dose is lower, Rafferty said.

She cautioned, however, that “full-field digital tomosynthesis is still in its infancy.” But, she predicted, “this technique will only get better.”

Other sources: American Roentgen Ray Society