====== Primary bone tumor ======

see [[Primary bone tumors of the spine]].

Primary tumors of bone can be divided into benign tumors and cancers. Common benign bone tumors may be neoplastic, developmental, traumatic, infectious, or inflammatory in etiology. Some benign tumors are not true neoplasms, but rather, represent [[hamartoma]]s, namely the [[osteochondroma]]. The most common locations for many primary tumors, both benign and malignant include the distal femur and proximal tibia (around the knee joint).

Examples of benign bone tumors include [[osteoma]], [[osteoid osteoma]], [[osteochondroma]], [[osteoblastoma]], [[enchondroma]], [[giant cell tumor]] of bone and [[aneurysmal bone cyst]].

Malignant primary bone tumors include [[osteosarcoma]], [[chondrosarcoma]], [[Ewing's sarcoma]], [[fibrosarcoma]], and other types.

While malignant fibrous histiocytoma (MFH) - now generally called "pleomorphic undifferentiated sarcoma" - primary in bone is known to occur occasionally, current paradigms tend to consider MFH a "wastebasket" diagnosis, and the current trend is toward using specialized studies (i.e. genetic and immunohistochemical tests) to classify these undifferentiated tumors into other tumor classes. Multiple myeloma is a hematologic cancer, originating in the bone marrow, which also frequently presents as one or more bone lesions.

[[Germ cell tumor]]s, including [[teratoma]], often present and originate in the midline of the [[sacrum]], [[coccyx]], or both. These sacrococcygeal teratomas are often relatively amenable to treatment.