Synovial sarcoma: clinicopathologic features, treatment, and prognosis.

Synovial sarcoma is a characteristic subtype of soft tissue sarcomas with a predilection for young people. There may be a long delay in diagnosis or misdiagnosis, because of its insidious growth, varied presentation on imaging studies and associated joint pain, which can be confused with trauma. Diagnosis requires a tissue sample in the form of a needle or open biopsy. The needle biopsy may not be representative of the tumor, particular if it is biphasic, and it may be necessary to proceed to open biopsy. Ideally, the biopsy should be performed by the surgeon who will be performing the definitive surgical resection. Although treatment is predicated on surgery, adjuvant radiation and/or chemotherapy may be beneficial, particularly in high risk patients. Significant prognostic factors include: size > 5 cm, deep-seated location, adequacy of surgical margins, and history of recurrence. In the future, multi-institutional prospectively randomized, controlled studies will be needed to better define the role of adjuvant chemotherapy. Currently, outcome may be optimized by early suspicion and detection with referral to an orthopedic oncology specialist prior to the biopsy.