The purpose of this research study is to evaluate how well the Stereo Navigator Biopsy Accessory for the PEM Flex solo II PET Scanner works for performing breast biopsy on suspicious lesions. This study will also allow the doctors to describe the features of PEM detected lesions and the results obtained using the PEM guided biopsy and will compare the time it took to complete a pre-operative work up using PEM versus MRI in patients with a suspicious breast lesion resulting in cancer.

See brief summary.

Inclusion Criteria:

• female
• subject is 25-100 years of age
• subjects has at least one breast imaging finding on mammography and/or ultrasound which is assessed as highly suggestive of malignancy and recommended to biopsy
• subject is able to provide informed consent

Exclusion Criteria:

• subject is pregnant
• subject is actively lactating or discontinued breastfeeding less than 2 months ago
• subject has breast implants
• subject is scheduled for sentinel node procedure using radioactive Tc-99m within 24 hours of the PEM study
• subject has contraindications for core biopsy and other invasive procedures
• subject has Type I diabetes mellitus or poorly controlled Type II diabetes mellitus
• subject has had surgery or radiation therapy on the study breast or has had chemotherapy within the past 12 months
• subject has not fasted for 4-6 hours prior to the procedure and/or have a fasting blood glucose level greater than 140 mg/dl on day of PEM imaging

Women 25 or older

One year and four months.