Solitary fibrous tumor of the orbit

Abstract
The differential diagnosis of discrete, intraconal orbital tumors includes a number of mesenchymal lesions, including hemangiopericytoma, fibrous histiocytoma, schwannoma, neurofibroma and some sarcomas. Solitary fibrous tumor is an uncommon neoplasm, first described in the pleura, that can be confused with these tumors. We report a case of a solitary fibrous tumor in the orbit. The histologic ‘patternless’ pattern and the immunochemical findings of uniform CD34 positivity should allow correct diagnosis of this lesion.