Fibrosarcoma of Bone

Fibrosarcomas of bone are typically seen between the third and sixth decades of life, most commonly in the metaphysis or metadiaphysis of the long tubular bones. Fibrosarcomas can be intramedullary (most common) or periosteal (rare, but better prognosis). They can also be categorized as primary or secondary.

Secondary fibrosarcoma of bone can arise from benign bone lesions (Paget disease, bone infarction, fibrous dysplasia, chronic osteomyelitis, giant cell tumor), malignant bone lesions (e.g., chondrosarcoma), or irradiated bone. Fibrosarcomas occurring in the spine or the flat bones are usually secondary lesions.

Radiographs typically reveal a large aggressive lytic lesion with cortical destruction and soft tissue extension. The location is typically metaphyseal and extension into the diaphysis and epiphysis is common.

Differential considerations for high-grade fibrosarcomas include:

• Multiple myeloma:
• Metastasis:
• Lymphoma:
• Malignant fibrous histiocytoma:

Low-grade fibrosarcomas can have more sclerotic and better-defined borders, and can be similar to:

• Desmoplastic fibroma:
• Chondromyxoid fibroma:
• Giant cell tumor:

References

Koplas M and Sundaram M. Fibrogenic and Fibrohistiocytic Tumors. in Imaging of Bone Tumors and Tumor-Like Lesions. Davies AM, Sundaram M, and James SLJ (eds). Springer-Verlag Berlin Heidelberg (2009); pp 310-311.