乳癌常轉移至骨骼。我們報告一乳癌合併骨轉移的病人，其PET造影爲陰性，但骨骼掃描及CT掃描爲陽性。一般而言，PET造影在診斷骨骼轉移較骨骼掃描更有專一性，亦有足夠的敏感度。若PET造影不能確診骨骼轉移，骨骼掃描及CT掃描可作爲確診的輔助工具。

Bone is one of the most common metastatic sites of breast cancer. We present a case of breast cancer with bone metastases and the patient was evaluated by FDG-PET/CT and a bone scan. The PET scan had a negative finding, but both bone and CT scans detected bone metastases. In general, FDG-PET has greater specificity and good sensitivity for detecting bone metastases. However, when FDG-PET scan findings are equivocal, additional findings from a bone or CT scan can be helpful in diagnosis of bone metastases.