[Imprint cytological features of soft tissue sarcomas]

The imprint cytologic features in typical sarcomas, such as malignant fibrous histiocytoma (MFH), fibrosarcoma, malignant peripheral nerve sheath tumor (MPST), liposarcoma, synovial sarcoma, clear cell sarcoma and epithelioid sarcoma, were presented in comparison with each histologic feature. Cytological diagnosis of soft tissue sarcomas is usually difficult because of their rarity, various kinds, wide range of features in the tumor and similar features to those of other tumors. Based on the cellular morphology, sarcoma cells were divided into five cell types as follows: small cell type, spindle cell type, epithelioid cell type, epithelioid-spindle type, and pleomorphic type. The results obtained from "retrospective" immunostainings for decolorized Papanicolau's stained sections with a panel of markers, together with differentiation of the cell type, were useful for the cytological diagnosis of the tumors examined. Since the value of aspiration cytology is much higher than that of imprint cytology in the cytopathologic diagnosis, methods, such as immunostaining and differentiation of the cell type, are recommended in aspiration cytology to make a definitive cytological diagnosis in sarcoma cases.