Aspiration cytology of intramuscular myxoma. A comparative clinical, cytologic and histologic study of ten cases.

Soft-tissue tumors are a fairly new area for aspiration cytology. As part of the correlation between the cytology and histology in these tumors, a retrospective study of ten intramuscular myxomas was conducted. All of the patients presented with a firm, painless intramuscular mass that was excised with different surgical margins; no recurrences were found at follow-up. The cytologic findings corresponded well with the histologic ones. Droplets of a highly viscous fluid typically characterized an aspirate from an intramuscular myxoma. The fluid was generally not very cellular. The cells had elongated cytoplasm and spindle-shaped nuclei. They varied in size and shape, and cellular atypia was minimal. Aspirates from low-grade myxofibrosarcoma and myxoid liposarcoma presented the main differential diagnostic problems.