Ossifying fibromyxoid tumor of the orbit

PURPOSE: This report describes the clinical, radiographic, and histopathologic features of the first known case of ossifying fibromyxoid tumor involving the orbit. METHODS: Case report and literature review. RESULTS: An 81-year-old woman presented with a 3-month history of diplopia, pain, and right upper eyelid swelling. CT and MRI of the orbit disclosed a 2.5-cm extraconal mass superomedially in the right orbit, with displacement of the globe inferiorly and remodeling of the orbital roof. During surgery, the tumor was noted to be firm, gritty, and extraperiosteal in location, and the bone adjacent to the tumor was irregular and abnormal in consistency. The tumor was removed intact without difficulty. Histologic, immunohistochemical, and transmission electron microscopic examination disclosed features consistent with ossifying fibromyxoid tumor. Fourteen months after removal, the tumor recurred and the patient underwent a second excisional biopsy. The tumor recurred a second time 30 months after the first surgery. The patient underwent a third surgery to remove the tumor and received adjuvant radiation therapy. She has been free of disease for more than 18 months. CONCLUSIONS: This is the first known case of ossifying fibromyxoid tumor involving the orbit. Increased cellularity, nuclear atypia, and mitotic activity have been associated with metastatic and recurrent potential. The tumor in this case had moderate cellularity, low nuclear grade, and no mitotic figures. However, the close proximity of the tumor to important structures within the orbit precluded its excision with wide margins and may have predisposed the patient to the two episodes of local recurrence.