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Osteoblastic versus osteolytic bone metastases
Bone metastases are often characterized by their radiographic appearance as either osteolytic, osteoblastic, or mixed.
Most patients with breast cancer have predominantly mixed or osteolytic lesions. In contrast, patients with prostate cancer are often found to have predominantly osteoblastic lesions. However, regardless of appearance, there is significant osteolytic activity. In fact, osteolytic activity in these lesions often is comparable with, if not higher than, that typically seen in breast cancer and multiple myeloma. Such activity has been demonstrated by markedly elevated biochemical markers of bone resorption in the serum and urine of such patients. Only in multiple myeloma do purely lytic bone lesions develop.
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