Primary synovial sarcoma arising in the parotid region diagnosed by fluorescence in situ hybridization.

Synovial sarcomas account for 5% of pediatric soft tissue sarcomas, and primarily arise in the extremities. We report a case of synovial sarcoma in the parotid region. A 29-year-old woman presented with a 3-year history of a slow-growing, slight painful swelling in the preauricular region. The patient underwent right deep parotidectomy preserved with facial nerve. In immunohistochemistry, the epithelial cells were positive for cytokeratin AE1/3 and epithelial membrane antigen. The stromal cells were immunoreactive for vimentin and BCL2. The both types of cells were positive for CD99. The SYT-SSX fusion gene from chromosomal translocation was detected by fluorescence in situ hybridization in this case.