Malignant Transformation of a Giant Cell Tumor of Bone Treated with Denosumab: A Case Report

Research paper by Park, A, Cipriano, C. A, Hill, K, Kyriakos, M, McDonald, D. J.

Indexed on: 10 Oct '16Published on: 28 Sep '16Published in: JBJS case connector


Case: Giant cell tumor (GCT) of bone was first described almost 200 years ago, but the optimal treatment continues to evolve. We present a patient with a pelvic GCT who was treated with embolization, 20 months of denosumab therapy, and resection. Histologically, the tumor consisted of degenerated GCT, bone, and fibrous tissue. After 7 months, the patient was found to have osteosarcoma at the site of the initial lesion as well as pulmonary metastases. Conclusion: The apparent malignant transformation of a GCT of bone treated initially with denosumab indicates that close follow-up is warranted.