Apport de l'irm dans les lésions infra-cliniques du sein

Dynamic-contrast-enhanced MR imaging is a sensitive method (95%) with a mild specificity (from 51% to 66%) for the characterization of nonpalpable breast tumors. Specificity of the analysis of breast nodules may be improved by using MR sequences with high temporal resolution (acquisition time <5 sec): in cancer, the enhancement is centripete whereas it is centrifuge in fibroadenoma. An early linear contrast enhancement is associated with ductal carcinoma in situ in 91% of cases. In most published data, the MR false-negative rate is inferior to 5% (carcinoma in situ, well-differentiated cancers and infiltrating lobular carcinoma.