SOLITARY FIBROUS TUMOR OF THE ORBIT

We report three cases of an orbital soft tissue lesion that fulfills t he histologic, immunohistochemical, and electron microscopic criteria for solitary fibrous tumor, an entity previously described as a pleura l tumor, but recently reported to occur in other locations. All three patients presented with proptosis. Two of the patients were cured by s imple excision, and one patient had two recurrences, the last recurren ce incompletely excised. The findings indicate that solitary fibrous t umor can occur in the orbit and, like solitary fibrous tumors of other anatomic sites, may behave in a nonaggressive or occasionally, locall y aggressive fashion, with as yet no metastatic potential demonstrated in orbital lesions.