Synovial sarcoma is a rare soft tissue sarcoma with biphasic features of both spindle cell and epithelial differentiation. Synovial sarcoma is a rare high-grade tumor that spreads along fascial planes and, thus, can be much more widespread than apparent on initial evaluation. Males are more commonly affected than females with a ratio of 1.1:1. Synovial sarcoma is characterized by a specific chromosomal translocation t(X;18)(p11;q11) that is observed in more than 90% of cases. The t(X;18)(p11;q11) translocation fuses the SYT gene from chromosome 18 to either of 2 homologous genes at Xp11, either SSX1 or SSX2. The fusion proteins SYT-SSX1 and SYT-SSX2 function as aberrant transcriptional regulators, resulting in either activation of protooncogenes or inhibition of tumor suppressor genes.
Kawai et al found that SYT-SSX fusion transcripts are a defining diagnostic marker of synovial sarcomas. These fusion transcripts may yield important independent prognostic information and provide important information for different types of treatment.
Answer 1: Myxoid liposarcoma is associated with chromosomal translocation t(12;16)
Answer 4: Ewing's sarcoma with t(11;22)
Answer 5: Clear cell sarcoma with (12;22), Myxoid Chondrosarcoma with t(9;22),
Menendez LR: Othopaedic Knowledge Update: Musculoskeletal Tumors, Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 11-20
Kawai A, Woodruff J, Healey JH, Brennan MF, Antonescu CR, Ladanyi M. SYT-SSX gene fusion as a determinant of morphology and prognosis in synovial sarcoma. New England Journal of Medicine, 338:153-160
PMID:9428816 (Link to Abstract)
Enzinger FM, Weiss SW: Soft Tissue Tumors, ed 4, St Louis, MO, Mosby, 2001, pp 1483 to 1571