Tumor maligno que se desarrolla a partir del tejido conectivo fibroso (fibroblasto).
   <(F.): Fibrosarcome, sarcome fibroblastique: sarcome constitué par une prolifération de fibroblastes élaborant une quantité variable de matériel fibrillaire.
   <(Ing): Fibrosarcoma: is an uncommon, malignant spindle cell neoplasm. It appears in the metaphysis or metadiaphysis of long bones. Fibrosarcoma is found most commonly around the knee in the distal femur and proximal tibia followed by the pelvis. The tumor produces a collagen matrix but does not produce osteoid or chondroid. Fibrosarcoma can be primary or secondary due to Paget's disease, fibrous dysplasia, irradiated giant cell tumor, bone infarct or chronic osteomyelitis. Fibrosarcoma occurs both as an intramedullary and periosteal lesion. It presents in adults age 30 to 60 years old and affects men and women equally. The most common clinical presentation is that of a localized, painful mass.