Radiological and Histopathological Outcome of Giant Cell Tumor of Femur with Denosumab Treatment: A Case Report.

Giant Cell Tumour of Bone (GCTB) is a benign but locally aggressive osteolytic skeletal neoplasm of young adults consisting of giant cells expressing RANK (Receptor Activator of Nuclear Factor-κB) and mesenchymal spindle-like stromal cells expressing RANKL (RANK ligand). The interaction of these cells leads to bone resorption. Recently, the RANKL inhibitor, denosumab, has demonstrated activity against giant-cell tumours. The current article reports a case of a Giant cell tumour of left distal femur with pathological fracture. A 34-year-old male patient presented with history of on and off dull aching pain in the left knee for 4 months followed by a history of trivial fall. He sustained a closed injury in the left knee, following which he was unable to bear weight and developed pain and swelling in left knee. Conventional radiographs and Computerized tomography (CT) was done which showed the presence of a left distal femoral osteolytic lesion and a histological analysis of a biopsy specimen confirmed the diagnosis of GCTB. The patient was treated with neoadjuvant denosumab therapy which resulted in successful downstaging of the tumour followed by extended curettage of the lesion with high speed burr and argon laser cautery. The post-curettage microscopic examination revealed the absence of osteoclast-type giant cells.