Sarcomas involving bone often present with pain and swelling after a long duration of symptoms. They may even grow large enough to threaten the structural integrity of the bone and cause pathologic fracture as the initial presentation.
Generally, lesions that involve more than 50% of the bone cortex, that are larger than 2 cm, or that involve the medial calcar of the femur are associated with the greatest risk of fracture. A prior history of bone infarct, irradiation, or other such risk factors should alert the physician to the possibility of a secondary fibrosarcoma.
Soft-tissue sarcomas most often present as painless masses. The time to presentation, however, is often shorter than with lesions involving bone. Because these lesions frequently arise deep to the muscular fascia, they may become extremely large tumors before being diagnosed.
-
Although fibrosarcoma of bone can arise anywhere, it is found most commonly about the knee and femur. The radiograph here shows a typical appearance of a lesion in bone.
-
Most pathologists describe the histologic picture of fibrosarcoma as a herringbone pattern. It is an interlacing pattern of sheets of spindle-shaped fibroblasts in a collagen background. This pattern is very distinctive and usually confirms the diagnosis of fibrosarcoma.
