MR imaging of medullary carcinoma of the breast

To examine the magnetic resonance imaging (MRI) findings of medullary carcinoma of the breast and to correlate them with histopathologic features.

Eight patients were retrospectively evaluated with pathologically confirmed medullary carcinoma of the breast. T1-weighted fat-saturated, T2-weighted fast spine echo, and gadolinium-enhanced fat-saturated fast spoiled gradient-echo images were obtained. Interpretation of the MRI findings was based on evaluation of the configuration, internal signal intensity, contrast enhancement, and type of the time-intensity curve.

Medullary carcinoma showed a lobular shape and a smooth margin, either homogenous or heterogeneous enhancement and delayed peripheral enhancement in the late phase on contrast-enhanced MRI, and either a plateau or washout type with rapid initial rise on the time-intensity curve of the dynamic study.

Although the MRI findings showed a close relationship with histopathologic features of medullary carcinoma, it was difficult to differentiate medullary carcinoma from other histologic types of invasive breast carcinomas.