This study recruits participants directly from Penn Medicine clinics, during time of their clinical biopsies. Up to 40 participants with known or suspected primary or metastatic breast cancer who meet eligibility requirements for this study will undergo FTT PET/CT study imaging. Each PET/CT scan will include an injection of up to 12 mCi (approximate range for most studies is anticipated to be 8-12 mCi) of [18F]FTT. Data will be collected to evaluate uptake of [18F]FTT in breast cancer and compare with PARP-1 activity in tissue, when available. If patients are getting neoadjuvant or other systemic therapy, a second optional scan may be performed 1 day to 3 weeks after therapy begins to evaluate whether response correlates with increase in PARP-1 activity.

You may be eligible for this study if you meet the following criteria:

• Conditions: Breast Cancer, Biopsy
• Age: 99 years or below
• Gender: All