We describe an interesting case-report represented by a patient carrying BRCA1 mutation, recruited for the study "Multicenter evaluation of Magnetic Resonance Imaging (MRI) in early diagnosis and prevention of breast cancer in high risk population", diagnosed with breast cancer on the basis of MRI findings but not with conventional mammography and ultrasound (US). She was already affected at 53 years of age by a multifocal Ductal Infiltrating Carcinoma (DIC) in the left breast; then, she had an axillary and sovraclavear nodal recurrence of the disease, three years after the initial diagnosis. Since other relatives were affected by breast cancer (mother, sister and niece) and two arose at early age (< 40 years), BRCA1 mutational analysis was offered to the patient, identifying a nonsense mutation on the exon 13. Furthermore, this patient was recruited to study contralateral breast and at the second round, two little foci, suspicious of malignancy, were identified only with MRI, but not with mammography and ultrasonography. The final diagnosis was multifocal Ductal Carcinoma in situ (DCIS); the major focus measured 3 mm. In our patient MRI has shown a major sensitivity with respect to conventional radiology and US and has provided a very early diagnosis in this woman at genetic risk.