Impact of 18F-FDG PET-CT Versus Conventional Staging in the Management of Patients Presenting With Clinical Stage III Breast Cancer

Inclusion Criteria: * Women (or men) with histological evidence of breast cancer for whom potentially curative treatment is planned. * Based on clinical information (physical exam, imaging): 1. Stage III breast cancer (T0N2, T1N2, T2N2, T3N1, 2 or T4), or 2. Stage IIb breast cancer (T3N0), Note: T2N1 is not eligible * Considered for combined modality therapy (surgical resection, chemotherapy, radiotherapy) of curative intent. Exclusion Criteria: * Age \< 18 years, * ECOG performance status \> and = 3, * Prior systemic therapy (e.g. neo-adjuvant chemotherapy or hormonal therapy) for current breast cancer, * Previous staging investigations for current breast cancer, * Breast cancer with primary histological subtypes other than ductal or lobular (Note: Patients with mixed disease will be eligible for randomization), * Clinical suspicion of metastatic disease, * Relative contraindications to PET (e.g. uncontrolled diabetes (i.e. inability to decrease serum glucose below 10.2 mmol/L), claustrophobia, inability to be still for 30 minutes), * Inability to lie supine for imaging with PET-CT, * Inability to undergo CT because of known allergy to contrast, * History of another invasive malignancy within the previous two years (exception of non melanoma skin cancer) or a synchronous primary cancer, including a synchronous contralateral breast cancer (Note: Patients found to have a contralateral breast cancer on study imaging following randomization will remain in the study), * Known pregnancy or lactating female, * Inability to complete the study or required follow-up.