Objective: To demonstrate non-inferiority of gadobutrol versus gadobenate dimeglumine by intra-individually comparing 0.1 mmol/kg body weight doses for contrast-enhanced breast magnetic resonance imaging (MRI) and prospectively evaluating lesion detection and characterisation in a multicentre trial.
Methods: Two identical breast MRI examinations were performed in 72 patients with biopsy-proven breast cancer, separated by 1-7 days. Gadobutrol 1.0 M or gadobenate 0.5 M were administered in a randomised order. Lesion detection and characterisation were performed by two independent blinded readers. Lesion tracking, which compared on-site readings and histology from surgery or biopsy, was performed by a third reader. Differences in lesion detection and characterisation were compared between the two contrast agents.
Results: Among 103 lesions, 96 were malignant and 7 were benign. No difference in lesion detection was identified between the contrast agents (82.33 % for gadobutrol, 81.60 % for gadobenate). Assessment of sensitivity in lesion characterisation and Breast Imaging Reporting and Data Systems showed no difference between gadobutrol (92.63 %) and gadobenate (90.53 %). Regarding morphology, there was more non-focal enhancement for gadobutrol than for gadobenate (P = 0.0057).
Conclusion: Non-inferiority of gadobutrol compared with gadobenate was demonstrated for breast lesion detection and sensitivity in lesion characterisation in breast MRI.