MESENCHYMAL CHONDROSARCOMA OF THE ORBIT - REPORT OF 3 NEW CASES AND REVIEW OF THE LITERATURE

Background: Extraskeletal mesenchymal chondrosarcoma is a rare tumor c haracterized by undifferentiated mesenchymal cells with islands of mat ure hyaline cartilage. Considering all sites, long-term survival is ap proximately 30%. Only seven cases of orbital mesenchymal chondrosarcom a have been reported. Methods: The records of three cases of orbital m esenchymal chondrosarcoma treated at the Columbia-Presbyterian Medical Center, and the seven previously reported cases of this tumor were re viewed to determine clinical characteristics and appropriate therapy. Results: Nine of the 10 patients were female; age of onset ranged from 10 to 35 years. Of eight patients with at least 2 years of observatio n, five survived 5 or more years after resection, or after resection p lus adjuvant therapy. Two patients died of metastatic disease 2 and 5 years, respectively, after the initial treatment, and one died of pneu monia 6 months after surgery. Review of the histology of the three cas es treated at Columbia-Presbyterian Medical Center did not identify di stinct histologic types that might guide therapy. Presenting symptoms were typical of symptoms of an orbital mass: proptosis, pain, diplopia , change in visual acuity, ptosis, and tearing. Conclusion: The small number of reported cases of mesenchymal chondrosarcoma of the orbit pr events definitive conclusions, but it appears that resection is adequa te therapy in some cases. Extraskeletal mesenchymal chondrosarcoma of the orbit may have a better prognosis than tumors in other sites.