- Tumor of mesenchymal cell origin that is composed of malignant fibroblasts in a collagen background.
- It can occur as a soft-tissue mass or as a primary or secondary bone tumor.
- Fibrosarcoma was diagnosed much more frequently in the past; it is now more reliably distinguished histologically from similar lesions, such as desmoid tumors, malignant fibrous histiocytoma, malignant schwannoma, and high-grade osteosarcoma.
- Fibrosarcoma represents only about 10% of musculoskeletal sarcomas
- Fibrosarcoma of bone can be diagnosed in patients of any age, but it is diagnosed more commonly in patients in the fourth decade of life.
- It is usually located in the lower extremities, especially the femur and tibia.
- Fibrosarcoma of the soft tissues usually affects a wider age spectrum of patients than fibrosarcoma of the bone does, with an age range of 35-55 years.
- It often arises in the soft tissues of the thigh and the posterior knee.
- It is generally a large, painless mass deep to fascia and has an ill-defined margin.
- An infantile form (in children <10 y) of fibrosarcoma exists. Unlike fibrosarcoma in adults, it has an excellent prognosis—even in the face of metastatic disease at presentation—when treated with a combination of neoadjuvant and adjuvant chemotherapy and resection.
 Imaging Findings
 See Also
 External Links
- Dickey ID. E-medicine ortho article