<unk> , or metastatic bone disease, is a class of cancer<unk>  that results from primary tumor invasion to bone.  Bone-originating cancers like osteosarcoma, chondrosarcoma, and Ewing's sarcoma are rare.  And, unlike hematological malignancies that originate in the blood and form non-solid tumors,<unk>  generally arise from epithelial tumors and form a solid mass inside the bone. <unk>  cause severe pain, characterized by a dull, constant ache with periodic spikes of incident pain.
Bone metastasis
Bone cancer
Osteomyelitis
Osteoma
Primary lymphoma of the bone
Bone infarction
Osteopetrosis
Osteochondrosis