Epithelioid Leiomyosarcoma of Skin: A case report

ABSTRACT

This report concerns a rare malignant smooth muscle neoplasm of the skin and the subcutaneous tissue, which was examined immunohistochemically and ultrastructurally. It occured in a 48-year-old female patient who had suffered from painful nodules on the left shoulder. The nodules were removed and diagnosed as a benign fibrohistiocytic tumor. One year after local excision, multiple nodules were detected by physical examination at the previous operation site. Grossly, thirteen well-defined small nodules had spread in the dermis and the subcutaneous tissue, of which nine were located from lower dermis to the subcutaneous tissue and four were in the subcutaneous tissue. Histologically, each nodule consisted mainly of epithelioid tumor cells having eosinophilic or clear plump cytoplasm and round to oval nuclei with small nucleoli, and some peripheral spindle tumor cells. The tumor cells were negative for PAS reaction with and without diastase digestion or alcian blue. Immunohistochemically, tumor cells were positive for smooth muscle actin and vimentin. Ultrastructurally, the tumor cells showed actin filaments and dense bodies in cytoplasm. This case was diagnosed as an epithelioid leiomyosarcoma of the skin and the subcutaneous tissue with local metastasis one year after local excision.