Enrolled women with breast cancers who had received an anthracycline-taxane regimen and subsequent surgery were prospectively enrolled. DCE-MRI and FDG-PET scan were performed before and after the 1st cycle of chemotherapy. MR imaging parameters and SUV on PET scan within a tumor were analyzed. Clinicopathologic (age, clinical tumor stage, hormonal receptor status, and surgery type) and imaging parameters were compared according to the pathological response.