Occult oncocytoma of the lacrimal sac.

Oncocytoma of the lacrimal sac is a rarely encountered clinical entity. We report the case of a 72-year-old female patient who was diagnosed to have bilateral nasolacrimal duct obstruction during a pre-cataract surgery screening. Subsequently, she underwent bilateral dacryocystectomy. Histopathological examination of the left lacrimal sac revealed a tumour composed of acini lined by oncocytic cells; features consistent with those of a lacrimal sac oncocytoma. Although rare, oncocytomas arising from the lacrimal sac may co-exist with a nasolacrimal duct obstruction. This report describes the histological and immunochemistry characteristics of oncocytomas and underscores the need to subject all excised lacrimal sacs to histopathological examination.