WASHINGTON – Magnetic resonance imaging screening for breast cancer is feasible and cost effective for high-risk underserved women, according to a study conducted by Duke University Medical Center researchers.
The investigators, led by Dr. Anne C. Ford, assistant professor of obstetrics and gynecology at the center, wanted to determine whether targeting MRI screening, which has the potential to increase the number of benign biopsies, would increase costs.
The researchers included 299 women who participate in a high-risk clinic at Duke, who were given a digital mammogram followed by an MRI, as well as 299 average-risk women recruited through an outreach program to serve as controls. High risk was defined as a greater than 20% lifetime risk of breast cancer, the investigators reported at a conference sponsored by the American Association for Cancer Research.
The women were racially diverse. The mammography group was 40% African American, 25% white, 25% Hispanic, and 10% other. The MRI group was 62% white, 33% African American, 3% Hispanic, and 2% other.
Women found to have an abnormal mammogram were evaluated by ultrasound, ultrasound-guided biopsy, and/or stereotactic biopsy. Women with an abnormal breast MRI were evaluated with ultrasound, ultrasound-guided biopsy, and/or MRI-guided biopsy. Patient navigators accompanied all women to all appointments, including follow-up care.
Overall, there were seven benign biopsies conducted in the mammography group. One cancer was found, for a detection rate of 12%. Thirty-one benign biopsies were done in the combination group; seven cancers were discovered, for a detection rate of 18%.
Of the cancers that were staged, the MRI had detected one stage 0 tumor, four that were stage I, and one each that were stage II and III. The mammogram detected one tumor that was stage II. So the MRI detected some cancers in an early stage.
For screening alone, the cost per diagnosis was $37,375 for mammography, compared with $27,722 for MRI.
These figures, however, were calculated using a lower MRI rate than many institutions might pay. For the study, the cost of the MRI was negotiated to a reduced rate of $649. Dr. Ford said in an interview that the calculation might change if the MRI rate were more or less.
There also was a very good compliance rate with follow-up studies. Most likely, that is because those services were offered free of charge to participants and because they were constantly interacting with patient navigators, said Dr. Ford.
Six of seven women in the mammography group who were referred for follow-up complied. Twenty-eight of the 31 MRI screening patients returned for follow-up.
The study was supported by the Susan G. Komen for the Cure, the Avon Foundation Breast Care Fund, the Kate B. Reynolds Charitable Trust, and the Breast Cancer Relief Foundation.