Early Interim 18F-FDG-PET and 18F-FLT-PET for Predicting Treatment Response and Survival in Metastatic Breast Cancer

Inclusion Criteria: * Participants must have histological evidence of breast cancer of any stage * Participants must be diagnosed with metastatic breast cancer * Participants should be willing and able to have both PET-CT scans * Participants should be eligible for and plan to undergo systemic chemotherapy and should be seen by a oncologist prior to beginning the study * Participants should have the ability to understand and the willingness to sign a written informed consent document * Participants must sign a study specific consent form prior to registration Exclusion Criteria: * Patients have been diagnosed with other malignancy * Patients with uncontrolled intercurrent illness including, but not limited to, ongoing or active infection or significant inflammation at treatment site or psychiatric illness/social situations that would limit compliance with study requirements or whose lab values do not meet the criteria above are excluded * Pregnant women are excluded from this study * Breast feeding women are excluded from this study