Abstract
We report the case of an anterior orbital tumor in a young woman that enlarged during pregnancy. The mass was excised and found to be a spindle cell tumor with immunohistochemical reactivity consistent with a solitary fibrous tumor, a rare entity in the spectrum of fibroblastic mesenchymal tumors. The tumor was strongly positive for the progesterone receptor, consistent with its clinical growth during the antenatal and postnatal periods. To our knowledge, a primary orbital tumor with these characteristics has rarely been reported in the literature.