The goal of this pilot project is to test the new Radialis Positron Emission Mammography (R-PEM) system in breast cancer patients that has a higher sensitivity with lower radiation doses than conventional PET/CT.

The plan for the pilot study is to image patients who are already scheduled for diagnostic imaging for breast cancer after a positive core biopsy. Participants will be injected with 5mCi (millicurie) of F18-Fluorodeoxyglucose (FDG) and patient will wait for a couple of hours for uptake of FDG. After this time, the first R-PEM scan will occur. Additional optional R-PEM scans can be performed 4 hours after injection and 7 hours after injection with reductions in radiation emission.

Additionally, R-PEM images will be compared to standard-of-care breast Magnetic Resonance Imaging (MRI) and digital breast tomosynthesis (DBT) to study extension of disease and screening of contralateral breast.

Inclusion Criteria:

• Subject is female of any race and ethnicity
• Subject is at least 26 years old
• Following routine mammography imaging, subject is categorized as BI-RADS score 4C or 5 because of calcifications, masses, asymmetries or/and architectural distortion will undergo additional tests including biopsy within 30 days of routine imaging
• Subject is female with a recent breast biopsy confirming breast cancer

Exclusion Criteria:

• Subject unable or unwilling to undergo informed consent
• Subjects who are unable or unwilling to tolerate any of the imaging tests because of claustrophobia, compression, etc.
• Subjects who are pregnant or who think they may be pregnant
• Subjects who are breast-feeding
• Subjects weight exceed table limits of MRI and PET-CT (300-450 lb or 135-205 kg)
• Subjects with history of allergic reaction to gadolinium or previous history of life-threatening anaphylactic reaction to any contrast.
• Claustrophobic subjects