PRIMARY SUBCUTANEOUS LEIOMYOSARCOMA EXHIBITING THE CHARACTERISTIC IMMUNOPHENOTYPE POSITIVE FOR VIMENTIN AND DESMIN

BACKGROUND. Primary subcutaneous leiomyosarcoma is a rare neoplasm composed of plump, elongated spindle cells arranged in interweaving fascicles. OBJECTIVE. Differential diagnosis might be facilitated by the use of immunohistochemistry, METHODS. A case of subcutaneous leiomyosarcoma was investigated histologically on paraffin-embedded tissue and immunohistochemistry was performed following standard procedures. RESULTS. The case reported exhibited light microscopic features and an immunophenotype characteristic of leiomyosarcoma. However, the intermediate filament desmin could only be found on a small number of tumor cells. CONCLUSiON. Expression of these markers might vary considerably and immunoperoxidase stainings need to be carefully evaluated. Utilization of several antibodies directed against different desmin epitopes might be advantageous. 20:541-543.