The purpose of this pilot clinical study is to test a methodology for using high-resolution Positron Emission Tomography (PET) imaging to guide vacuum-assisted core biopsy of breast abnormalities identified on PET. In order to implement the PET guidance, the study uses the Stereo Navigator accessory to the high-resolution organ-specific PET scanner (PEM Flex™ PET Scanner, Naviscan PET Systems, Inc., San Diego, CA). The Stereo Navigator is an investigational device intended for guiding biopsy needles toward lesions in breasts identified by a physician on a high resolution PET image. The study will evaluate the clinical utility of the Stereo Navigator in guiding the vacuum-assisted core biopsy of breast abnormalities, following the example of prior studies of breast biopsy guided by magnetic resonance imaging (MRI)

The study will invite participation from human subjects with newly diagnosed or suspected breast cancer who have one or more breast abnormalities moderately suspicious or highly suggestive of malignancy on breast imaging and requiring biopsy (the lesion(s) of interest). Prospective subjects will be asked to sign IRB-approved consent forms, explaining the use of PET imaging for guiding biopsy of suspicious lesion(s). Up to 30 patients will be recruited in the study. The study will be terminated after approximately 20 subjects undergo PET-guided interventional procedures. In the course of the study, a subject will be injected with 18F-FDG and imaged using the PEM Flex PET scanner. Once an abnormality requiring biopsy is identified on the PET scan, the physician conducting the procedure will use the PET image to plan the biopsy trajectory using the Stereo Navigator Software Module, and use the Stereo Navigator Needle Guide Holder to guide insertion of the introducing stylet toward the lesion. The sampling will be performed using commercially available core biopsy tools routinely used for MRI-guided biopsy.Immediately after the PET-guided biopsy, conventional biopsy markers will be inserted at the biopsy site(s) for correlation with other imaging modalities. Placement of the biopsy marker will be documented using mammography, as per standard clinical practice. Histopathologic results will be correlated with imaging findings. The procedure may be repeated for additional lesions identified on PET at the investigator's discretion.

Inclusion Criteria:

Individuals aged 25 years or older

• Individuals who have at least one breast imaging finding requiring biopsy, specifically:

  • Individuals who have a breast abnormality(ies) moderately suspicious for or highly suggestive of malignancy on imaging with mammography, ultrasound, or MRI (as per ACR BIRADS™ 4C or 5) and requiring biopsy confirmation OR o Individuals with known breast cancer who have additional imaging abnormality(ies) suspicious for malignancy detected on a high-resolution FDG PET scan
  • Individuals who had recent conventional imaging work-up including x-ray mammography of the breast containing the abnormality of interest.

• Individuals with suspected tumor size measuring one cm or less on mammography and/or ultrasound and/or MRI if the lesion is visible on any of these modalities, except that each site may enroll up to three patients each where the lesion of interest as measured on mammography (or ultrasound and/or MRI if not detectable on mammography) is more than 1 cm. (Note: The study will target patient enrollment such that at least 50% of the lesions to undergo biopsy across all sites will be less than 1 cm in diameter as measured on mammography, or as measured by other modalities, such as ultrasound, CT, or MRI, if the lesion is not detectable or measurable on mammography.)

• Individuals who have agreed to participate in the study and who have signed study-specific informed consent

Exclusion Criteria:

• Women who are or may be pregnant
• Women who are currently lactating or discontinued breastfeeding < 2 months prior to the study
• Age less than 25 years
• Individuals with breast implant(s) in the breast containing the lesion of interest
• Individuals who are scheduled for a sentinel node procedure using radioactive Tc-99m within 24 hours of PET-guided biopsy
• Patients with contraindications for core biopsy and other invasive procedures such as blood coagulation disorders, infection, or who are unwilling to discontinue use of anticoagulant medication prior to the procedure
• Individuals with Type I or poorly controlled Type II diabetes mellitus
• Individuals with a blood glucose level that is above 140 mg/dl at the time of PEM imaging
• Inability to provide informed consent
• Individuals who have had surgery on the study breast(s) within the past 12 months