Breast Cancer Patients' Best Friend
If you're at high risk for breast cancer, MRI technology may be your new best friend. In an effort to provide a better option than prophylactic mastectomy for high-risk patients, Ellen Warner, MD, led a team of researchers at the Toronto Sunnybrook Regional Cancer Centre in Toronto to study the effectiveness of MRI. "Up to now," she said, "all we've been able to offer high-risk women is standard mammography, which does not work well in young women, and follow-up with clinical exams, which may not find cancer until very late. MRI is the most sensitive screening tool we currently have, and with a careful screening protocol and follow-up, there is a good possibility that we can find cancer early enough in high-risk women to cure it."
The study involved 236 women between the ages of 25 and 65. These women were in the very highest risk category of all -- carriers of mutations in the genes BRCA1 and BRCA2, which means that they have an 85% lifetime risk of developing breast cancer. All study participants received three yearly screenings -- MRI, mammography and ultrasound -- and two yearly breast exams by health professionals at six-month intervals over the six-year study period. In all, 22 cancers were found -- 16 breast cancer tumors and six precancerous tumors. An amazing 77% of cancers were discovered through MRI, while 36% were discovered through mammography, 33% through ultrasound and 9% through clinical breast exam. Even more significant is that 32% of cancers were detected only by MRI but were missed by the other screening methods (10% were detected by mammography alone and 10% by ultrasound alone).
WHAT ABOUT THE REST OF US?
Since it is so effective, shouldn't all women have MRI screenings? Dr. Warner says no, because the false positive rate is high. She explains that if you do an MRI on 100 women, there will be about seven false positive biopsies in the first year and three or four true positives for cancer -- the false positive to true positive ratio is about 2:1. A high false positive rate is acceptable in high-risk women because there will be more cancer found, but it is not acceptable to perform MRI in low-risk women, because there will probably be no cancer. She defines high-risk women as either proven mutation carriers, and/or those with a family history of early-onset breast cancer in several relatives, and/or those who already have had breast cancer.
A US STUDY
A similar MRI screening study is being conducted at the National Cancer Institutes of Health Center for Cancer Research in Bethesda, Maryland. To speak with the recruitment nurse, Stephanie Steinbart, call 800-518-8474 or call the Clinical Studies Support Center at 888-624-1937. All calls are completely confidential.