Primary Orbital Chondromyxoid Fibroma: A Rare Case.

A 56-year-old male with history of chronic sinusitis was found to have a 3 cm left orbital lesion on CT. Subsequent MRI demonstrated a multilobulated enhancing soft tissue lesion at the superotemporal region of the left orbit. Initial biopsy was reported as a low-grade sarcoma. On further evaluation, a consensus was made that the lesion was likely a benign mixed mesenchymal type tumor but should nonetheless be surgically removed. Left lateral orbitotomy was performed which revealed a tumor originating in the lateral orbital bone with segments eroding through the wall of the orbit. Intraoperative frozen sections revealed myoepitheliod tissue with locally aggressive features and the tumor was completely removed. The final histopathologic analysis of the tissue was consistent with a chondromyxoid fibroma. Chondomyxoid fibroma is a rare entity in the orbital bones and is more commonly seen in long bones.