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Three-dimensional technology -- known as three-D -- gives depth to objects that would otherwise appear two-dimensional, or flat. Three-D makes movies and video games look more realistic. And now it could help save lives.

For years, mammograms have played an important role in finding breast cancer. But these X-ray pictures of the human breast often miss dangerous lumps or tumors.

And they also produce false positives. A false positive wrongly appears to show suspicious tissue. And that causes painful, unnecessary biopsies to examine that tissue.

A new study shows that three-D technology could change the way doctors look for breast cancer.

A woman undergoes a mammography exam, a special type of X-ray of the breasts used to detect tumors.

When Zulima Palacio discovered she had breast cancer, it already had reached stage three. That means that the cancer was very dangerous.

"Even a month before it was detected, I went for a sonogram and they told me, 'You're fine, go home.'"

Ms. Palacio is now cancer free. But the standard two-dimensional mammogram missed all three of her tumors.

Many doctors - including cancer surgeon Negar Golesorkhi - say standard mammography does not find enough cancerous tumors. She says looking for cancer in dense, thick breast tissue is like looking for a polar bear in a snow storm. In other words, it is very difficult.

"When we look for cancer on a mammogram in a dense breast tissue, we're looking for a polar bear in a snow storm, so it would be very difficult to find."