Synovial sarcoma of the parapharyngeal space

Synovial sarcoma is a rare soft tissue sarcoma in the head and neck region and parapharyngeal space. A 21-year-old girl presented with a 6-month history of progressive right arm pain, neck mass and upper aerodigestive tract obstruction. On physical examination there was a large painless mass arising from the right-sided parapharyngeal space causing airway obstruction and with no cervical lymphadenopathy. Initial magnetic resonance imaging (MRI) revealed a large tumor in the right-sided parapharyngeal space. She underwent near total resection of the tumor. Pathologic report disclosed the diagnosis of synovial sarcoma. She then received postoperative adjuvant external radiotherapy to the primary site and a dose of 60 Gy was delivered. Less than 8 months after the completion of the treatment she developed widespread lung metastases. Herein we describe the clinical, radiological and pathological finding of the case.