Synovial sarcoma of the larynx treated by partial laryngectomy.

Synovial sarcomas of the head and neck are rare, fewer than 50 having been reported. Synovial sarcoma of the endolarynx is extremely rare, only one previously reported case appearing in English literature. Contrary to earlier beliefs, this tumor does not arise from the synovial lining of joints and bursa but develops from pleuripotential mesenchymal cells through abnormal differentiation into synovial neoplasms. Microscopically the tumor is characterized by a biphasic pattern of pseudoepithelial cells and a spindle cell element with fibrosarcomatous appearance. One additional case of synovial sarcoma of the endolarynx is reported. The tumor arose from the right subglottic area and presented submucosally. It was treated by extended frontolateral partial vertical (hemi) laryngectomy. The patient is alive and well 3 years after surgery. This case is the first reported to be successfully treated by partial laryngeal surgery alone. The histopathology of synovial sarcoma is reviewed and details of the biopsy and surgical technique are presented. This single case might suggest that early synovial sarcoma of the larynx is locally nonaggressive.