EXTRASKELETAL MESENCHYMAL CHONDROSARCOMA OF THE ORBIT

Mesenchymal chondrosarcoma, an uncommon lesion of bone and extraskelet al tissue, is rare in the orbit. A case of extraskeletal mesenchymal c hondrosarcoma of the orbit in a 28-year-old woman presenting with prop tosis and diminution of vision in the left eye is reported. Histologic ally, the tumor showed areas of undifferentiated mesenchymal cells wit h islands of cartilage. Immunohistochemical analysis for S-100 protein showed focal positivity in chondroid areas. The eye was preserved and the patient has good vision after 2 years of follow-up.