Synovial sarcoma of bone: Sarcoma typically of soft tissues presenting as a primary bone tumor

Synovial sarcoma typically presents as periarticular soft tissue mass in adolescent and young adult patients. Very rarely, soft tissue sarcomas may arise primarily within bone posing a significant diagnostic challenge as primary osseous malignancies such as osteosarcoma and metastatic disease are much more common. While tissue sampling with immunohistochemical and genetic testing are required for definitive diagnosis, radiologists and orthopedic oncologists should consider alternate etiologies when typical imaging features of more common bone tumors are not identified. As an example, we present a 33-year-old male referred with a pathologic hip fracture proven to represent primary synovial sarcoma of bone.