Markers that are commonly expressed on synovial sarcoma cells include epithelial membrane antigen (EMA) [10], BCL-2 [11], and vimentin [12], while markers such as protein S-100 [12], CD99 [6], CD34 [6], actin [12], and desmin [12] are mostly negative. The gene discussed is CD99; the disease is synovial sarcoma.