Early Breast Cancers Caught by MRI
Follow-Up MRI Breast Cancer Screening May Reduce Biopsies
June 16, 2003 -- Follow-up breast cancer screening using
magnetic resonance imaging (MRI) can track and catch some of the smallest,
early breast cancers in high-risk women while they are most susceptible to
treatment. A new study shows follow-up MRI can detect curable early breast
cancers that cannot be found by mammography or physical exam.
Researchers say the study, published in the July 15 issue of
Cancer, is the first to examine "probably benign" findings from
MRI breast cancer screening among women at high risk of developing breast
cancer due to a family history of the disease or previous breast cancers.
Although breast cancer screening using MRI is very good at
picking up the tiniest abnormalities in the breast, it can also pick up benign
or normal growths in breast tissue. Researchers say MRI screening is less
accurate at determining which of these growths may be cancerous, and the
outcome of probably benign growths detected by MRI has not been studied until
Tracking Early Breast Cancers With MRI
In this study, researchers followed 367 women at high risk for
developing breast cancer who had normal mammograms and were referred for
further screening using MRI.
Follow-up breast cancer screening using MRI is frequently
recommended for tracking growths or abnormalities in the breast that doctors
believe are probably noncancerous or benign. Researchers say breast cancer
screening has several advantages over biopsy in this regard because it is
noninvasive, less expensive, and causes less anxiety for the patient than
biopsies, which require removal of breast tissue with a needle for further
Breast cancer screening using MRI found "probably
benign" growths in 89 of these women (24%). Follow-up MRI screening was
performed for 79% of these women after an average of 11 months. Most of the
women who were referred for follow-up MRI had multiple growths, usually in both
Twenty of the 89 women subsequently had a biopsy after
follow-up MRI due to progression of the growth. Breast cancer was found in nine
women. This means that approximately 10% of the women initially diagnosed with
probably benign growths had early breast cancer.
Many Respond to Treatment
Researchers say more than half of the breast cancers found were
ductal carcinoma in situ (DCIS), a type of cancer that responds well to
treatment when caught in the early stages.
The study also found more than half of the breast cancers
identified were detected by MRI alone, not by conventional methods.
"These data indicate that follow-up breast MR imaging in
high-risk women can detect early breast [cancer] before it can be diagnosed by
mammography or physical examination," write researcher Laura Liberman, MD,
and colleagues at the department of radiology at Memorial Sloan-Kettering
Cancer Center in New York City.
Researchers say more study is needed among larger groups of
women to determine the most appropriate intervals for follow-up breast imaging
using MRI. MRI breast screening is currently recommended only for women at high
risk for breast cancer because it is relatively new and significantly more
expensive than traditional mammography screening.