[Clear cell sarcoma: a clinicopathological study of 11 cases].

The clinicopathologic, ultrastructural and immunohistochemical features of eleven cases of clear cell sarcoma are described. There were 6 males and 5 females with an average age of thirty-six (10-59 years). Tumors were found arising from the tendons, aponeuroses and fascial structures with a predilection for the lower and upper extremities. Follow-up data was available in 8 patients. Five of them are alive. Nevertheless, 3 of the five showed evidence of recurrence or metastasis. The other 3 patients died of tumor with metastasis. Microscopically, the tumors were composed of short fascicles of fusiform cells with a clear to eosinophilic cytoplasm and vesicular nuclei with prominent nucleoli. Melanin was demonstrated in 5 cases and S-100 was known present focally in all cases, but no positive keratin staining was obtained. Electron microscopic studies revealed cell attachments and mature melanosomes. The exact histogenesis remains obscure, but our ultrastructural and immunohistochemical findings support the idea of neural crest origin of this tumor.