Molecularly confirmed primary prostatic synovial sarcoma

We report the second molecularly-confirmed primary prostatic synovial sarco ma. The diagnosis was particularly elusive at the light microscopic level i n that the tumor failed to show epithelial differentiation, but it did show combined spindle-cell and poorly differentiated (round-cell) morphologies. The immunohistochemical staining profile was nonspecific and potentially m isleading Only by demonstration of the characteristic SYT-SSX gene fusion o f synovial sarcoma by reverse transcriptase polymerase chain reaction (RT-P CR) analysis of RNA extracted from archival material could the diagnosis be con firmed. This case further illustrates the use of this technique in dia gnostic pathology Copyright (C) 2000 by WR. Saunders Company.