Dedicated Breast MRI Delivers High Diagnostic Accuracy

Dedicated breast MRI systems offer significant improvement in performance and diagnostic accuracy, said researchers in a study published in the October issue of the journal Radiology.

Researchers assessed the sensitivity and specificity of images of 934 patients (347 screening exams and 587 diagnostic exams) from April 2006 to December 2007. The women were between the ages of 25 and 89. The images were taken by Aurora Imaging Technology Inc.’s dedicated 1.5-T breast MR system that used high-spatial-resolution, high-contrast-resolution spiral trajectory acquisitions.

Results showed sensitivity for the dedicated MRI system of 92 percent (92 women out of 100) and specificity of 88.9 percent (741 women out of 834). The negative predictive value for screening cases was 100 percent. The area under the receiver operating characteristics (ROC) curve was 94 percent. The false-positive rate was 93 of 834 (11.2 percent) for all cases, but only 16 of 326 (4.9 percent) for the screening cohort.

“False positive rates from previously reported trials using whole-body breast MRI have typically been between 30 and 50 percent,” study investigator Alan Hollingsworth, MD, said in a release. Hollingsworth is the medical director and a breast surgeon at Mercy Women’s Center at Mercy Health Center.

“These studies have led to criticism of breast MRI for its high false positive rates, resulting in unnecessary biopsies, surgical procedures and anxiety for the patient,” he said. “The dedicated breast MRI system offers a significant improvement in performance. Even with 93 false positives, 25 (27 percent) were high-risk histologies for which excision is often recommended. This kind of performance should provide breast radiologists and surgeons alike a higher level of diagnostic confidence and could have significant impact on the role of breast MRI.”