Breast MRI Useful Adjunctive Tool for Inconclusive Digital Breast Tomosynthesis

Breast MRI is a useful adjunctive tool when there are inconclusive digital breast tomosynthesis (DBT) findings, according to a study published in the American Journal of Roentgenology.

Researchers from Massachusetts, Florida, Nevada, and Michigan sought to evaluate the utility of MRI as a problem-solving tool for equivocal findings on diagnostic digital mammography (DM) and DBT.

The researchers retrospectively reviewed 5,330 MRI examinations performed from March 2011 to November 2014 to identify examinations performed to further assess equivocal findings on combined DM and DBT (DM/DBT) examinations. All patients underwent diagnostic ultrasound in conjunction with their DM/DBT examination. Imaging reports were retrospectively reviewed for BI-RADS findings and assessments of diagnostic DM/DBT and diagnostic MRI examinations. A review of the electronic medical records provided information on demographic data, cancer diagnoses, and pathologic findings.

Related article: Supplemental Breast MRI Widely Underutilized in High-Risk Women

The results showed that of the total MRI examinations performed, 67 (1%) were performed for evaluation of an equivocal finding, including:

• 27 asymmetries (40%)
• 16 focal asymmetries (24%)
• 5 masses (7%)
• 19 architectural distortion (28%)

MRI correlates were identified in 22 of 67 examinations (33%). Biopsies yielded a cancer diagnosis for five of 67 patients (7%).

98%

The frequency of recommendations for breast MRI to evaluate equivocal findings decreased exponentially in the three years after DBT implementation.

The researchers concluded that as clinical implementation of DBT becomes increasingly widespread, breast radiologists need an algorithm for addressing the small number of inconclusive findings that remain equivocal despite thorough DM/DBT and ultrasound examinations. Breast MRI is a useful adjunctive tool for these selected cases.