A Case of Fibrosarcoma Arising in Giant Cell Tumor of Bone: a Rare Entity

Excerpt

Giant cell tumor of bone is a rare primary skeletal lesion accounting for approximately 5% of all primary bone tumors. Although classified as a primary benign bone tumor, a giant cell tumor of bone has a high recurrence rate reaching 65%, along with the potential for malignant transformation. Malignant giant cell tumors can be divided into primary and secondary forms. Tumors where the malignant sarcomatous components are present de novo in conjunction with a giant cell tumor of bone are termed as primary malignant giant cell tumors [1] and are exceedingly rare. These tumors can also be described by the term “dedifferentiated giant cell tumors” [2]. Secondary malignant giant cell tumors are those high-grade sarcomas which arise at the sites of previously treated benign giant cell tumor of bone. This category is more common occurring several years after the primary radiation therapy or much less commonly after surgery [2, 3]. …