Clear cell sarcoma (CCS), first described by Enzinger in 1965, is a rare soft tissue tumor. Before this, this uncommon neoplasm had been misdi- agnosed as fibrosarcoma, synovial sarcoma, heman-SJ Jung, et al. giopericytoma, alveolar soft-part sarcoma, and hemangioendothelioma. It occurs most frequently in the feet and ankles of women in the second and third decades. The tumor is characterized by multiple local recurrences with late metastases and a high rate of deaths. It usually presents as a slowly growing mass and occasionally causes mild pain or tenderness. Symptoms may persist for a long time (mean of 5 years) before the patient seeks medical attention.
Gross pathologic examination of CCS reveals a localized, tan-gray, firm and somewhat circumscribed mass, varing in size from 0.4 cm up to 14.5 cm. Frequently, the mass is attached to tendons or aponeuroses, but there is no direct connection with overlying skin. On microscopic analysis, epithelioid cells with pale nuclei and deeply basophilic nucleoli are aggregated in compact nests surrounded and separated from adjacent nests by fibrous tissue septa. Mitoses are generally sparse and necrosis and haemorrhage are rare. canadian antibiotics
On immunohistochemical examination, the tumor cells of nearly all cases express S-100 protein. Most of them also express antigens associated with melanin synthesis (HMB-45, melanin-A, Mel- CAM). Cytokeratin, epithelial membrane antigen, carcinoembryonic antigen, desmin, and smooth muscle actin are usually negative. In our case, staining the tumor cells showed positive reaction to S-100, Vimentin and negative reaction to Ki-67, CD34, SMA, Desmin.