Three cases of histiocytic sarcoma.

Abstract

Three cases of histiocytic sarcoma were reported. Neoplastic cells in these cases posessed cytoplasm which was S100 protein and α1 antitrypsin positive but lysozyme negative, suggesting T zone histiocyte origin. Interdigitation was observed electron microscopically in case 2. However different results in immunohistochemical staining were observed among these cases. For example, LCA and OKT4 positive tumor cells were observed only in case 2 and Ki-1 positive cells in case 1 and 2. Erythrophagocytosis was observed only in tumor cells of case 3 obtained at autopsy. The patients were young (16, 48 and 19 years old respectively), and had multiple metastases involving extranodal organs.