Malignant oncocytoma of the lacrimal sac as an unusual cause of epiphora.

A 72-year-old man presented with a 2-year history of epiphora. CT revealed an extensive inferomedial orbital tumor connected to the lacrimal sac and duct. Incisional biopsy revealed malignant oncocytoma of the lacrimal sac. The patient was treated with exenteration and maxillectomy followed by a course of postoperative radiotherapy. Patients with malignant oncocytoma may present with simple epiphora in absence of other signs and symptoms such as blood stained tearing or purulent rhinorrhea.