<unk> -cell<unk>  of the bone accounts for 4-5% of primary bone<unk> s and about 20% of benign bone<unk> s. However, significantly higher incidence rates are observed in Asia, where it constitutes about 20% of all primary bone<unk> s in China. It is slightly more common in females, has a predilection for the epiphyseal/metaphyseal region of long bones, and generally occurs in the third to fourth decade. Although classified as a benign<unk> , GCTOB has been observed to metastasize to the lungs in up to 5% of cases, and in rare instances (1-3%) can transform to the malignant sarcoma phenotype with equal disease outcome.
Giant-cell tumor of bone
Osteomyelitis
Fibrocartilaginous mesenchymoma of bone
Osteoid osteoma
Osteoblastoma
Osteoma cutis
Fibrous dysplasia of bone
Bone cyst