PRIMARY RETROPERITONEAL SYNOVIAL SARCOMA

We present a patient with primary retroperitoneal synovial sarcoma whi ch showed a monophasic fibrous pattern, the fourth such case to be des cribed, and a review of the literature. Synovial sarcoma cells in the present case were stained positive for cytokeratin and epithelial memb rane antigen (EMA), of which histology was differentiated from other s pindle cell sarcoma with similar light microscopic features. Retroperi toneal synovial sarcoma is usually treated surgically, however only on e of 16 cases identified in the literature survived five years after r esection. Due to the high fatality rate, physicians should be alerted to the possibility of this disorder in the differential diagnosis of a n abdominal mass.