title: P63 Positive Mucoepidermoid Tumor of the Lacrimal Sac with Associated Papilloma.
abstract: We report a case of a 44-year-old man who presented with a left medial canthal mass and epiphora. Imaging was suggestive of a mass continuous with the nasolacrimal sac. Subsequent surgical exploration revealed a mass adherent to bone with invasion of the lacrimal system. Histological examination revealed a squamous/transitional cell papilloma overlying a low-grade mucoepidermoid carcinoma (MEC). Complete surgical resection was completed and pathology confirmed the diagnosis. This is the first case in which a MEC has been reported concurrently with an overlying papilloma, providing support for the hypothesis that MECs arise from papillomas in the lacrimal sac. Additionally, the tissue stained positive for p63, which is congruent with MEC immunoreactivity in the salivary gland. The description of these unique histopathological findings may assist in definitive diagnosis and improve our understanding of the pathophysiology underlying lacrimal sac MEC tumors.
authors.affiliation: Schulich School of Medicine and Dentistry, University of Western Ontario , London, Ontario , Canada .
authors.forename: Yiannis
authors.initials: Y
authors.lastname: Iordanous
authors.forename: Jillian C
authors.initials: JC
authors.lastname: Belrose
authors.forename: Dani C
authors.initials: DC
authors.lastname: Cadieux
authors.forename: Subrata
authors.initials: S
authors.lastname: Chakrabarti
authors.forename: James P
authors.initials: JP
authors.lastname: Farmer
authors.forename: Larry H
authors.initials: LH
authors.lastname: Allen
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005134:Eye Neoplasms / Q000175:diagnosis / Q000601:surgery*; D006801:Humans; D007765:Lacrimal Apparatus / Q000473:pathology / Q000601:surgery*; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D018298:Mucoepidermoid Tumor / Q000175:diagnosis / Q000601:surgery*; D010212:Papilloma / Q000175:diagnosis / Q000601:surgery*; D014057:Tomography, X-Ray Computed
chemical_list: C081876:CKAP4 protein, human; D008565:Membrane Proteins
keywords: Histopathology; lacrimal sac; mucoepidermoid carcinoma; p63; papilloma