A bone tumor refers to a neoplasic growth of tissue in bone. It can be used for both benign and malignant abnormal growths found in bone, but is most commonly used for primary tumors of bone, such as osteosarcoma. It is may be applied to secondary bone tumors, i.e. metastatic tumors found in bone.

Classification

Bone tumors may be classified as "primary tumors" which originate in the bone, and "secondary tumors" which originate elsewhere.

Primary tumors

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. Examples of benign bone tumors include osteoma, osteochondroma, aneurysmal bone cyst, and fibrous dysplasia.

Malignant primary bone tumors include osteosarcoma, chondrosarcoma, Ewing's sarcoma, malignant fibrous histiocytoma, fibrosarcoma, and other sarcoma types. Multiple myeloma is a hematologic cancer which also frequently presents as one or more bone tumors.

The tailbone is a common location for a teratoma, known as a sacrococcygeal teratoma, and related germ cell tumors.

Secondary tumors