Magnetic resonance imaging (MRI) in the assessment of patients with breast carcinoma: an audit of accuracy

The aim of this audit was to assess the accuracy of breast magnetic resonance imaging (MRI) in patients with biopsy proven breast carcinoma. Indications were detecting multifocal disease, assessing extent of primary tumour and excluding recurrence.

Nineteen patients with known breast carcinoma detected on mammography, ultrasound or clinical examination were referred for MRI at 1T with bilateral breast coils. Pre-contrast and dynamic post contrast scans with subtraction were performed.

Nineteen patients had 21 histologically proven lesions. These included 13 invasive ductal carcinoma, two invasive lobular carcinoma, one medullary carcinoma and five benign lesions. MRI detected all of these and eight new lesions. Histological confirmation was available on two of eight new lesions detected by MRI. These represented 5- and 7-mm foci of invasive ductal carcinoma, one correctly predicted to be malignant in the contra-lateral breast. The other, thought to be benign, was removed at wide local excision of the known carcinoma. Six of the eight lesions had benign MRI features. Eleven months of clinical follow up revealed no abnormality.

Two follow up scans following surgery and radiotherapy were normal. Nine months of clinical follow up revealed no recurrence. We concluded that breast MRI is a reliable adjunct in pre-operative assessment and follow up of patients with known carcinoma.