A<unk>  is a primary malignant bone tumour, a type of sarcoma that starts in the bones. This is in contrast to most bone cancers that are secondary having developed as a metastasis from another cancer.<unk> s are rare, and mostly affect the legs. The other type of sarcoma is a soft-tissue sarcoma. There are three main types of<unk>  based on tissue type – an osteosarcoma, a Ewing's sarcoma, and a chondrosarcoma.
Bone sarcoma
Osteoma
Osteosarcoma
Bone metastasis
Osteoblastoma
Bone cyst
Osteochondrosis
Osteopetrosis