Objectives: In grade III-IV breast cancer, dissemination of disease needs to be assessed. Until now this was done by conventional imaging (liver ultrasonography, chest X-ray and bone scintigraphy), but evidence favoring the use of FDG-PET/CT is accumulating. Methods: Patients with high-risk breast cancer, who had received conventional imaging and FDG-PET/CT, were included. Patients were staged and assigned a treatment after 1) conventional imaging and 2) FDG-PET/CT, both by a multidisciplinary oncology team. Equivocal FDG-PET/CT findings were histologically confirmed. Results: 16 patients were included (mean age 59 years). TNM-stage changed in 5 patients (31%) after FDG-PET/CT. In 3 patients (19%) unknown distant metastases were detected by FDG-PET/CT. An adjustment of treatment took place in 4 patients (25%). Conclusions: Our case series emphasizes the role of FDG-PET/CT in the staging of high-risk breast carcinoma, especially in the assessment of distant metastases. We suggest replacing conventional imaging with FDG-PET/CT.