Ultrasound plus mammography finds more cancers, but increases false positives

Adding ultrasound to mammography finds more cancers than mammography alone, but also substantially increases the number of false positives, according to first-year results from a three-year study of the two tests.

“At this point, it’s not clear whether the benefit provided by ultrasound outweighs the additional expense, stress and inconvenience caused by the false positives,” said study co-author Etta Pisano, M.D., vice dean for academic affairs in the University of North Carolina at Chapel Hill School of Medicine, Kenan professor of radiology and biomedical engineering and director of the UNC Biomedical Research Imaging Center.

“We know that ultrasound does find more cancers. The question is, does it find enough more cancers to make it worthwhile?” she said.

The results were presented today (Sept. 28) at the American College of Radiology’s fall meeting in Washington, D.C.

The study’s principal investigator and lead author is Wendie A. Berg, M.D., Ph.D., of American Radiology Services, located at Johns Hopkins at Greenspring Station in Lutherville, Md. UNC Hospitals is one of the primary study sites, with an enrollment of 198 women (7.5 percent of the study participants).

In the study, 2,637 women at high risk for breast cancer received both mammography and ultrasound exams. The tests were performed by physicians who received special training in breast ultrasound screening. Among the participants, 41 breast cancers were found in 40 women (one had cancer in both breasts) by one or both of the tests. Twelve of the cancers were found by ultrasound alone.

The addition of ultrasound resulted in 136 (5.2 percent) women having biopsies due to suspicion of cancer. Of these women, 14 or 8.5 percent were diagnosed with breast cancer.

Based on these results, the authors concluded that adding ultrasound to mammography will find approximately an additional one to seven cancers per 1,000 high-risk women who had not previously been screened by ultrasound, but will also substantially increase the number of false positives.

“We had hoped to see a bigger effect of ultrasound compared to mammography,” Pisano said. “But I think these results show it’s a mixed picture at this point.”

Pisano said that the study will add magnetic resonance imaging (MRI) exams in its third year, allowing researchers to directly compare the effectiveness of MRI, ultrasound and mammography.

“At that point we will have good data on the cost-effectiveness of MRI versus ultrasound on top of mammography,” she said. “That will be the definitive analysis.”

Source: University of North Carolina at Chapel Hill

Related stories:

Kylie's breast cancer triggered a surge of over 30 percent in breast imaging of low-risk women
Kylie's breast cancer triggered a surge of over 30 per cent in breast imaging of low risk women, says new University of Melbourne study.
Adding ultrasound to mammography may improve breast cancer detection in high-risk women
The addition of an ultrasound examination to mammography for women at high-risk of breast cancer resulted in a higher rate of cancer detection, but also increased the number of false-positive results, according to a study in the May 14 issue of JAMA.
Adding ultrasound screening to mammography brings benefits, risks
Adding a screening ultrasound examination to routine mammography reveals more breast cancers than mammography alone, according to results of a major new clinical trial. The trial, however, also found that adding an ultrasound exam also increases the rate of false positive findings and unnecessary biopsies.
Procedure to detect fetal heart defects is first automated use of 3-D ultrasound
GE Healthcare, the leading manufacturer of 3D/4D ultrasound systems, has licensed a technique patented by an Eastern Virginia Medical School (EVMS) obstetrician that can automate the acquisition of ultrasound images used by physicians to diagnose fetal heart defects. GE Healthcare has licensed the software for exclusive use in its 3D/4D ultrasound systems.
Breast MRI spots other cancers, may alter treatment plan
In about 20 percent of women with breast cancer who plan to undergo a lumpectomy, breast magnetic resonance imaging reveals important diagnostic information that alters their treatment plan, University of Florida surgeons reported today (Dec. 5).
Screening MRI allows detection of more breast cancers in high-risk women
Magnetic resonance imaging (MRI) enables radiologists to accurately identify tumors missed by mammography and ultrasound, according to a multicenter study comparing the three screening methods in women at high-risk for breast cancer. The findings of the study appear in the August issue of the journal Radiology.
Magnetic resonance imaging improves breast cancer diagnosis
Women who have been diagnosed with breast cancer in one breast have a higher risk of contracting the disease in their opposite breast as well. A thorough examination of the opposite breast using mammography and ultrasound is therefore common practice. However, many tumours still remain undetected when using mammography. Magnetic resonance imaging (MRI) promises better results, as is shown in an inter-national study involving the University of Bonn.
New breast CT scanner rivals mammography
At the Radiological Society of North America meeting in Chicago on November 27, researchers will unveil a new imaging system developed at the University of Rochester that showed in a pilot study it could capture images equal to or, in a few cases, better than mammography.

News discussion:

Medicine & Health news