Malignant transformation of orbital solitary fibrous tumor.

Orbital solitary fibrous tumor (SFT) is a rare tumor and may recur or undergo malignant transformation without complete excision. We present a case of orbital SFT which recurred twice and underwent malignant transformation. The patient was treated with en bloc excision via a lateral orbitotomy. The postoperative histopathologic diagnosis of this case was an adult fibrosarcoma. Postoperative adjuvant radiation therapy was given. In 18 months of further follow-up, there has been no evidence of recurrence, both clinically and in regular imaging studies.