these results and the observations made on the cutaneous fibrous histiocytomas , atypical fibroxanthomas , dermatofibrosarcoma protuberans , and the various soft tissue sarcomas indicated that 1 ) alpha 1-antitrypsin is a valuable marker of histiocytic differentiation in both benign and malignant fibrous histiocytomas , 2 ) ferritin can be visualized in more than half of these fibroblastic-histiocytic tumors , and the presence of ferritin distinguishes the spindle cells of these tumors from fibroblasts of connective tissue and most fibrosarcomas , and 3 ) lysozyme , although a good marker of histiocytic differentiation in ordinary histiocytes and benign fibrous histiocytomas , is a poor marker of neoplastic histiocytes of malignant tumors .
C0002991
cutaneous
C0016030
fibroblasts