Giant cell tumor of the bone involving radius - a rare presentation. It is normally seen at the ends of the long bones and it is purely lytic (radiolucent) in most cases. The above example is accompanied by secondary aneurysmal bone cyst and prominent periosteal new bone formation making a radiological diagnosis almost impossible. Microscopy was typical, however. The patient, a 50-year-old man, had no lesions in the other bones. Image courtesy of Bulent Celasun, MD, Ankara, Turkey. Used with permission.