Multimodal ultrasound assessment of mass and non-mass enhancements by MRI: Diagnostic accuracy in idiopathic granulomatous mastitis and breast cancer

Purpose: Idiopathic granulomatous mastitis (IGM) poses diagnostic challenges due to its diverse clinical and radiological presentations, often mimicking malignancies. This study aimed to assess the diagnostic efficacy of multimodal ultrasound for mass and non-mass enhancements in Dynamic Contrast-Enhanced MRI (DCE-MRI) of IGM and breast cancer.

Methods: A retrospective analysis involved patients confirmed histopathologically with IGM and BC. All patients underwent conventional ultrasound (C-US), ultrasound elastography (UE), contrast-enhanced ultrasound (CEUS), and DCE-MRI examinations. Blinded experienced radiologists assessed imaging findings. Diagnostic accuracy, sensitivity, and specificity were calculated for mass and non-mass enhancements.

Results: For mass enhancements (ME), multimodal ultrasound demonstrated strong efficacy (AUC = 0.8651, 95 % CI: 0.7431 to 0.9871), exhibiting high sensitivity (83.3 %) and specificity (92.4 %) in differentiating IGM from breast cancer. However, for non-mass enhancements (NME), multimodal ultrasound showed limited accuracy (AUC = 0.6306) with lower sensitivity (65.6 %) and specificity (81.2 %) in distinguishing between IGM and breast cancer.

Conclusion: Multimodal ultrasound displayed good diagnostic efficacy for mass enhancements in DCE-MRI for IGM and breast cancer, while for non-mass enhancement patterns, DCE-MRI remains the most valuable radiological modality for comprehensively assessing this condition's complexities.