Measurement of bone mineral density as an efficacy marker in denosumab treatment of giant cell tumour of bone.

Three patients with giant cell tumour of bone (GCTB) in the lower extremity, where the only surgical treatment options were amputation or severe weakening of the bone, were treated with denosumab (D-mab) to strengthen the bone mass in the tumour. In order to quantify changes in bone mineral density (BMD) in the GCTB lesion during D-mab treatment, we did repeated dual-energy X-ray absorptiometry (DXA) scans. The patients underwent operation after 3, 4 and 8 months of D-mab treatment, respectively.