Case 51 Answer 2
MRI in this case will add little in diagnostic value. We don't really need to confirm that this is cancer. It obviously involves the entire breast, and a mastectomy is indicated. The breast is mostly fat on the right, but it is true one will be able to assess for small mammographically occult tumors on the opposite side (assuming bilateral scanning).
However, MR is useful in the assessment of neoadjuvant chemotherapy. The mammogram and ultrasound can only assess for the size and appearance of the tumor as it responds (or doesn't) to chemo. The MR can show enhancement as well, which often dimishes even when the bulk of the tumor looks the same by other criteria.