But only 7.4 percent of those women ended up actually having breast cancer. The findings highlighted concerns that increased detection of breast abnormalities may lead to finding more cancer when there is none, called a false positive. High numbers of false positives could result in unnecessary biopsies and other medical procedures without an actual benefit for women's health.
"The fundamental problem is that we have no evidence that detecting these cancers by ultrasound actually saves lives," Dr. Daniel Kopans, a professor of radiology at Harvard Medical School, told ABC News last week. "With all the effort that has gone into ultrasound screening over the last decade, it is surprising that no one has done a randomized, controlled trial, which is the only way to know if finding these cancers actually saves lives."
Smith said more research on the use of ultrasound and other supplemental imaging is certainly needed, but researchers may find that the risk of finding something that turns out to be nothing may be worth it for some women.
"It may be that the combination of supplemental imaging has higher false positive rate, but I think we can accept a higher false-positive rate if a woman's risk is higher," he said. "Women have said pretty clearly, whatever the risk of a false positive is, they place a higher priority on finding breast cancer early."