Image IQ: 81-year-old Screening Mammo Recalled Due to Mass

An 81-year-old woman presents for a routine screening mammogram (Figure A). The patient is recalled due to a mass seen in the lateral right breast. On the right magnification craniocaudal view (Figure B) an irregular mass measuring 0.9 cm is noted. This is also seen on the right medial lateral view as well (Figure C). On ultrasound (Figure D) the mass is seen 4 cm from the nipple measuring 0.9 cm.  A biopsy is performed showing Invasive Ductal Carcinoma. 

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What next step will provide additional information for surgical planning?