The role of magnetic resonance imaging in the assessment of local recurrent breast carcinoma.

Experience with magnetic resonance imaging (MRI) of the breast remains limited. MRI studies to date have shown that differentiation of carcinoma from certain benign breast changes can be difficult. The problem of suspected tumour recurrence in patients with known but treated breast carcinoma is considered. Forty-five patients were studied, all having been treated by lumpectomy combined with radiotherapy and/or chemotherapy. Suspicion of recurrence was suggested by X-ray mammography or clinically by the presence of a current breast mass, breast pain, or nipple discharge. The principle differential diagnosis rested between post-treatment fibrosis and recurrent tumour. Axial and sagittal images were obtained using T1-and T2-weighted pulse sequence. Images were enhanced with intravenous gadolinium DTPA in cases where there was a mass. The tomographic format and inherent high soft tissue contrast provided by MRI are of particular value in this situation. The morphological appearances of recurrent tumour, fibrosis, and other post-radiation affects are described and compared. MRI allowed accurate differentiation in the majority of case. In equivocal cases enhancement of mass lesions with gadolinium DTPA provided excellent confirmatory evidence of recurrent tumour.