Malignant fibrous histiocytoma of the lateral conjunctiva and anterior orbit.

A 25-year-old woman presented for evaluation of a rapidly enlarging mass of the left bulbar conjunctiva. Debulking biopsy was performed, which led to the diagnosis of myxoid malignant fibrous histiocytoma. The patient underwent left orbital exenteration with clear margins. Histopathology showed involvement of the conjunctiva substantia propria, superior conjunctival fornix, and episclera, as well as extension from the lateral rectus muscle sheath. Immunohistochemical staining was strongly positive for CD68, alpha1-antitrypsin, CD34, and vimentin.