Women at high risk for developing breast cancer should add an MRI exam to their annual mammography, the American Cancer Society (ACS) recommends.
The updated ACS guidelines say MRIs are prudent for women who have:
• A lifetime risk of breast cancer of at least 20% on standard risk models.
• A BRCA1 or BRCA2 genetic mutation or a parent, sibling or child who has one of the cancer-susceptibility mutations.
• Received radiation treatments to the chest between the ages of 10 and 30 for such conditions as Hodgkin’s disease.
• Li-Fraumeni syndrome, Cow-den syndrome or Bannayan-Riley-Ruvalcaba syndrome or have a parent, sibling or child with any of these rare maladies.
“As with other cancer screening tests, MRI is not perfect and, in fact, produces more false positives than mammography. [But] women at very high risk can be diagnosed much earlier when combining the two technologies rather than with mammography alone,” said Christy A. Russell, MD, a University of Southern California oncologist who chairs the ACS breast cancer advisory group.
Citing insufficient information, the ACS made no recommendations for or against MRIs for women with intermediate risk. The scans are not recommended for women with a lifetime risk below 15%, which includes survivors of cancer in one breast (CA Cancer J Clin. 2007;57:75-89).
Meanwhile, a multicenter study suggests that women who have cancer diagnosed in one breast would benefit from an immediate MRI of the other. Previous studies have shown that about 10% of breast cancer patients will develop malignancies in the contralateral breast.
The 969 women in the new study were recently diagnosed with unilateral breast cancer and showed no abnormalities, either clinically or mammographically, in the contralateral breast. But MRIs found early-stage tumors in 30 women (3.1%). All lesions were small and node-negative.
Such early detection would allow patients to undergo simultaneous instead of multiple treatments. And negative findings might reassure women considering prophylactic mastectomies, so they can avoid unneeded surgery (N Engl J Med. 2007;356: 1295-1303).