Myxoid tumor of soft tissue.

Focal myxoid change is a well-recognised feature of synovial sarcoma, but the presence of a predominantly myxoid stroma is rare. We describe a new case of myxoid synovial sarcoma in which marked myxoid change initially obscured the diagnosis leading to confusion with malignant peripheral nerve sheath tumor. The patient was a 16 year old man who presented with a left dorsal foot tumor. The diagnosis of synovial sarcoma was suspected on histological and immunohistochemical studies and confirmed with cytogenetic analysis. Recognition of this rare histologic variant of synovial sarcoma is important because it can easily be mistaken for other myxoid spindle cell neoplasms, potentially resulting in suboptimal therapy.