Purpose: The detectability with magnetic resonance mammography (MR-M) of non-invasive ductal carcinoma in situ (DCIS), its morphology, and patterns of contrast enhancement were studied.
Material and methods: A total of 849 MR-M examinations were performed in 741 patients using a dynamic, contrast-enhanced FLASH 3D sequence at 1.0 T. Surgical breast biopsies were obtained in 332 cases. Histological work-up confirmed 164 carcinomas, including 20 DCIS.
Results: Of 20 DCIS, 14 were correctly diagnosed by MR-M on the basis of focal increase of signal intensity. In two cases (10%), no increase of signal intensity was observed. In another three cases (15%), multifocal enhancement lead to a false-negative diagnosis. In one case (5%), DCIS was a random finding in a patient diagnosed and treated for adjacent phylloides tumour. The sensitivity of MR-M was 70%. 4 (20%) of the DCIS did not show microcalcifications at conventional mammography and were only detected at MR-M. The sensitivity of conventional mammography also amounted to 70%. However, the combination of both imaging methods increased sensitivity to 90%.
Conclusion: Ductal carcinoma in situ is not reliably detectable by MR-mammography alone due to lack of a uniform pattern of enhancement.