Fig. (2) Radiographic findings for case 1. This preoperative plain radiograph shows the osteolytic lesion at the proximal tibia (A, white arrow). Bone formation is apparent at 8 months after curettage (B, white arrow). However, osteolytic change had progressed at 16 months after the curettage. A plain radiograph shows osteolytic lesions at 20 months after curettage (C, white arrow). The osteolytic lesion was enhanced extremely by Gd in MRI simultaneously (D, white arrow).