A 59-year-old female patient having a history of right modified radical mastectomy 16 years previously due to breast cancer had developed bone metastases and 6 cycles of chemotherapy were administered. After the completion of chemotherapy, FDG-PET/CT was ordered to evaluate prolonged thrombocytopenia. PET/CT showed moderately heterogenous increased FDG uptake in the axial skeleton suspicious of bone marrow involvement. Bone marrow biopsy proved solid metastasis with carcinoma consistent with breast cancer. Her Hgb was 9.6 g/dL, WBC 7,400 and platelets 78,000 per µL at the time of biopsy.