Cytology of synovial sarcoma metastases in pleural fluid.

Report is made of the cytology of pleural fluid arising from extensive pleuropulmonary metastases of a biphasic synovial sarcoma of the leg of a 35-year-old male. Both fibrous, spindle-shaped and epithelioid types of tumor cells were present. The epithelioid cells were seen in groups or arranged in glandlike structures. Transformation of the fibrous, spindle-shaped tumor cells into the epithelioid ones was observed, suggesting that these two types of tumor cells are cytogenetically related.