This is a 16-years old girl with a mature skeleton who had an osteolytic lesion in the distal tibia with a narrow zone of transition extending up to the articular surface. The MRI shows fluid-fluid levels, suggesting an aneurysmal bone cyst (ABC) component, but the plain radiograph appearance is typical of a giant cell tumor (GCT). The CT scan shows an expansile lesion without abnormal trabeculation, again a finding in favor of GCT. A CT guided biopsy was done and histopathology shows a classic GCT with ABC transformation


#CTbiopsy #giantcelltumor #aneurysmalbonecyst