PSMB5 and synovial sarcoma: Synovial sarcoma is a well-established translocation-associated sarcoma and is defined by the presence of the t (X;18) (p11.2; q11.2) translocation, involving the SS18 (formerly SYT) gene on chromosome 18 and one of several synovial sarcoma X (SSX) genes on chromosome X (usually SSX1 or SSX2) [2].