Osteoblastoma

**Semantic type:** Neoplastic Process

**Definition:** A rare benign bone-forming neoplasm usually arising from the spine. It is a well-circumscribed lytic tumor that varies in size. The tumor is composed of woven bone trabeculae and shares similar histologic characteristics with the osteoid osteoma. Surgical curettage is the treatment of choice. The prognosis is excellent.

**Synonyms:** - Giant Osteoid Osteoma - Giant Osteoid Osteoma - Giant osteoid osteoma - OSTEOBLASTOMA, BENIGN - Ossifying Giant Cell Tumor - Ossifying Giant Cell Tumor - Osteoblastoma, NOS