The overall goal of this study is to determine how FDG-PET, breast MRI and breast ultrasound can be incorporated into the assessment of treatment responses in women with LABC undergoing neoadjuvant chemotherapy. A prospective cohort study will be conducted evaluating the ability of FDG-PET, breast MRI and breast ultrasound to detect the presence of residual tumour in patients with LABC who have completed treatment with neoadjuvant chemotherapy prior to mastectomy.