MRI finds cancers in opposing breast of women newly diagnosed with cancer
MRI scans of women who were diagnosed with cancer in one breast detected more than 90 percent of cancers in the opposite breast which had been missed by mammography and clinical breast exam, according to a new study published in the New England Journal of Medicine.
Adding an MRI scan to a breast evaluation is able to nearly doubled the number of cancers immediately found in these women.
"One in 10 women diagnosed with cancer in one breast will develop the disease in the opposite breast. Having a better technique to find these cancers as early as possible will increase the chances of successful treatment," said National Institutes of Health Director Elias A. Zerhouni, MD.
The trial, run by the American College of Radiology Imaging Network and sponsored by the National Cancer Institute, recruited 1,007 women from 25 institutions who had a recent diagnosis of cancer in one breast. All of the women enrolled had a negative mammogram and negative clinical breast exam of the opposite breast within 90 days prior to the MRI. After receiving an MRI, 33 contralateral breast cancers were diagnosed in the study. Thirty of these tumors, or 91 percent, were diagnosed as a result of MRI. The other three cancers were detected following mastectomies.
"This study gives us a clearer indication that if an MRI of the opposite breast is negative, women diagnosed with cancer in only one breast can more confidently opt against having a double, or bilateral, mastectomy," said NCI Director John E. Niederhuber, MD.
"We can now identify the vast majority of contralateral cancers at the time of a woman's initial breast cancer diagnosis," said Constance Lehman, MD, PhD, principal investigator of the ACRIN Breast MRI Trial, professor of radiology and director of breast imaging at the University of Washington and Seattle Cancer Care Alliance. "This means that instead of those women having another cancer diagnosis years after their initial treatment, we can diagnose and treat those opposite breast cancers at the time of the initial diagnosis."
Because of these findings, researchers hope breast MRIs will help avoid some unnecessary mastectomies and add reassurance for women that they are disease free. "Although no imaging tool is perfect, if the MRI is negative, the chance of cancer in that breast is extremely low. A potential outcome that we would be delighted to see is fewer unnecessary bilateral mastectomies," said Lehman.